Timewave PK-12 Operating Manual

PK-12

Operating Manual

Timewave Technology Inc.
1025 Selby Ave, Suite 101
St. Paul, MN 55104

http://www.timewave.com

TW P/N VA.06012

May, 1997

ii / PK-12 Packet Controller Operating Manual

W elcome

Thank you for purchasing an Timewave/AEA product! Before you go any further, please fill out and
return the enclosed Warranty Registration Card. Periodically, Timewave offers updates to its prod­ucts—we can only tell you about these updates if we have your warranty card on file, so send it in if
you haven’t already done so.

FCC Regulations

This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC Rules. These rules are designed to provide reasonable protection
against harmful interference in a residential installation. This device generates, uses, and can radiate
radio frequency energy and, if not installed and used in accordance with the instructions, may cause
harmful interference to radio communications. However, there is no guarantee that interfer ence will
not occur in a particular installation. If this device does cause harmful interference to radio or tele­vision reception, which can be determined by turning the device off and on, the user is encouraged
to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the device and receiver.

• Connect the device into an outlet on a circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Changes or modifications not expressly approved by the manufacturer will void the user’s au­thority to operate the device.

Disclaimer

As part of its continuing program of product improvement, Timewave reserves the right to make
changes in this product’s specifica tions or documentation. Timewave also reserves the right to incor­porate and issue any information thus supplied in whatever manner it deems suitable, without incur­ring any obligations whatsoever.

Copyright

©1997 by Timewave Tec hnology Inc. All rights reserved.
Under the copyright laws, this manual can’t be reproduced in any form without prior written permis-

sion from Timewave Technology Inc. No patent liability is assumed, however, with respect to the
use of the information contained herein.

This manual may contain errors, omissions or “typos.” Please send your comments, suggestions and
corrections to: Timewave Technology Inc., 501 W. Lawson Ave., St. Paul, MN 5511

7.

PK-12 Packet Controller Operating Manual / iii
PK-12 Packet Controller Operating Manual / iii

Table of Contents

FCC Regulations............................................................................................................................................ii

Introduction....................................................................................vii

Overview............................................................................................................................. vii

Typographical Conventions.........................................................................................................................vii

Abbreviations used throughout the manual..............................................................................................viii

1. The PK-12.....................................................................................1

Capabilities & Features ................................................................................................................................1

What You Should Have Received ..................................................................................................................1

Your Computer..............................................................................................................................................1

2. Power Supply & Computer Installation...................3

Overview............................................................................................................................... 3

Connecting Power ................................................................................................................. 3

Turning it On ......................................................................................................................... 3

Re-Initialization ................................................................................................................... 3

Connecting Your Computer to the PK-12............................................................................... 4

The Cable......................................................................................................................................................4

Dumb Terminals............................................................................................................................................4

The Computer ....................................................................................................................... 5

The Software......................................................................................................................... 6

PC Compatible Computers............................................................................................................................6

Installing PC PakRatt Lite.............................................................................................................................6

System Start-up and Loop-back T est.................................................................................... 7

3. Radio Installation ........................................................................9

To Transmit and Receive. . . ..........................................................................................................................9

Radio Connection Requirements........................................................................................... 9

Basic Connections and Adjustments ................................................................................... 10

Connections for Specific Transceivers.................................................................................. 10

Transceiver Adjustments..................................................................................................... 11

4. You’re in Command ....................................................................13

Parameters and Arguments ............................................................................................... 13

Changing Commands .......................................................................................................... 14

List of Commands ............................................................................................................... 14

PK-12 Command Quick Reference....................................................................................... 50

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5. Packet Operation........................................................................53

The Packet Modes............................................................................................................... 53

Tuning in Packet Stations — VHF/UHF ............................................................................... 53

What It Means............................................................................................................................................54

Who’s Out There?.......................................................................................................................................55

Talking to Yourself.............................................................................................................. 56

Setting Up for Transmitting ................................................................................................ 57

Calling CQ ..................................................................................................................................................58

Going On the Air.........................................................................................................................................58

More Packet Features......................................................................................................... 59

Nodes and Node Operation................................................................................................ 59

Operating Your Node..................................................................................................................................60

Digipeating ................................................................................................................................................62

Are You a Digipeater? ................................................................................................................................63

Identifying as a Digipeater ........................................................................................................................63

Time-stamping Packets and Messages .......................................................................................................63

Multiple Connection Operation........................................................................................... 63

Setting Up...................................................................................................................................................64

The Channel Switching Character...............................................................................................................64

CHCALL........................................................................................................................................................65

Checking Your Connect Status with CSTATUS ..............................................................................................65

Packet Meteor Scatter Extension........................................................................................ 65

Intermediate and Advanced Commands ............................................................................ 66

Monitoring Other Stations..........................................................................................................................66

Monitoring the Packet Networking Switches..............................................................................................66

Selective Monitoring...................................................................................................................................66

Monitor Without Call Sign Headers............................................................................................................66

Beacon Operation.......................................................................................................................................67

Packet Transmit Timing...............................................................................................................................67

Packet Formatting and Editing........................................................................................... 68

(RETURN)’s and Linefeeds ..........................................................................................................................68

Cancelling Lines and Packets .....................................................................................................................68

Redisplaying Text........................................................................................................................................68

The PASS Character.....................................................................................................................................68

Packet Protocol Basics........................................................................................................ 68

Reducing Errors through Collision Avoidance .............................................................................................69

DAMA Support.............................................................................................................................................70

CHECK and RELINK .....................................................................................................................................70

Transparent Mode.......................................................................................................................................70

Full-Duplex Operation................................................................................................................................71

Morse ID in Packet......................................................................................................................................71

The QRA Feature.........................................................................................................................................71

Packet Mail......................................................................................................................... 71

PK-12 Packet Controller Operating Manual / v
PK-12 Packet Controller Operating Manual / v

6. MailDrop Operation ...................................................................73

MailDrop Memory............................................................................................................... 73

Setting Up Your MailDrop ................................................................................................... 73

Accessing and Commanding Your MailDrop........................................................................ 74

Monitoring Your MailDrop.................................................................................................. 74

MailDrop Prompts and Operation...................................................................................... 75

Sending Mail....................................................................................................................... 78

From the Console Operator ........................................................................................................................78

Sending Other Types of Messages ..............................................................................................................79

From the User’s Point of View....................................................................................................................79

Message Numbers ......................................................................................................................................80

Forwarding and Reverse-Forwarding.........................................................................................................81

Settings for Auto-Forwarding .....................................................................................................................81

Entering a Message for Reverse Forwarding...................................................................................... ........81

7. GPS Operation............................................................................83

Hardware Configurations ................................................................................................... 84

Installing APRS ................................................................................................................... 86

Setting Up the PK-12 for GPS Operation ........................................................................... 86

Stand Alone Tracking Device Set-up:..........................................................................................................86

APRS Hardware Single Port Mode (HSP) Set-Up.........................................................................................88

APRS Dual Port Mode Set-up:.....................................................................................................................89

Building your own APRS adapter cable.............................................................................. 89

Connecting the APRS adapter cable ...........................................................................................................89

Schematic Diagram for the APRS Adapter Cable ................................................................ 90

PK-12/ULTIMETER II® Stand Alone Weather Station Set Up.............................................. 90

Wireless Data/Location Tracking Applications ................................................................... 91

Connecting the GPS Adapter Cable to the TNC: .........................................................................................93

8. Troubleshooting .........................................................................93

A Troubleshooting Primer................................................................................................... 93

The Power Supply Cable.............................................................................................................................94

The PK-12 ...................................................................................................................................................94

Cable from PK-12 to Computer ..................................................................................................................94

Computer/Software.....................................................................................................................................94

Cable From PK-12 to Radio ........................................................................................................................94

Radio ..........................................................................................................................................................94

If You Need to Call for Help ................................................................................................ 95

General Error Messages ..................................................................................................... 96

Packet Error Messages ....................................................................................................... 97

MailDrop Error Messages................................................................................................... 98

PK-12 Status and Error Messages...................................................................................... 98

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Out-of-the-Box Problems ................................................................................................... 99

Computer to PK-12 Problems........................................................................................... 100

Radio to PK-12 Problems................................................................................................. 100

MailDrop Problems .......................................................................................................... 100

Packet Problems............................................................................................................... 101

PK-12 Problems................................................................................................................ 105

Appendix A: Radio Connections ...................................................107

Radio Connection Notes.................................................................................................... 107

Radio Listings................................................................................................................... 108

Radio Connection Diagrams ............................................................................................. 112

Appendix B: Parts List, Schematic, and Pictorial Diagram...........117

Appendix C: Specifications ...........................................................120

Modem Characteristics ..................................................................................................... 120

Processor System.............................................................................................................. 120

Input/Output Connections ................................................................................................ 120

Controls and Indicators .................................................................................................... 120

General............................................................................................................................. 120

Appendix D: Battery Power..........................................................121

Setting the PK-12 to Low Power mode............................................................................. 121

Power Cable...................................................................................................................... 121

Additional Power Conservation........................................................................................ 121

Appendix E: Upgrading the PK-12 ...............................................122

Appendix F: Limited Warranty .....................................................123

Index ............................................................................................125

Introduction

Overview

The PK-12 is a 1200 baud, packet-only controller that sets a new standard in the amateur radio
world. As a new owner, however, you may be bewildered by its scores of commands and their func­tions, besides wondering what all those lights on the front panel do or mean.

Take heart: You don’t need to be a rocket scientist to understand how to hook up your PK-12 and op­erate it, but you do need to have an understanding of basic electronics so y ou can make the neces­sary (and correct) connections to your station equipment. You also need to have a working knowl­edge of your computer’s software, hardware and operation.

PK-12 Packet Controller Operating Manual / vii

Just as a car’s owner’s manual isn’t written to teach you how to drive, this one won’t go into the
electronics, operation, or theory behind packet operation, so please refer to other sources if your in­terest in the PK-12’s operation extends beyond its practical application.

Here are some excellent sources for reading more about packet and packet operation:

• The Radio Amateur’s Digital Communications Handbook by Jonathan Mayo, KR3T; TAB Books,
ISBN 0-8306-8362-3 (hardback) and 0-8306-3362-6 (pbk.).

• The ARRL Operating Handbook and Your Packet Companion by Steve Ford.

Both of the above are available from the ARRL, 225 Main Street, Newington, CT 06111-1541 or
your local ham radio dealer.

Typographical Conventions

To set off special text, this manual uses the following typographical conventions:
This kind of type identifies variables for which you enter values (f or example, MYCALL

This kind of type indicates a section of importance.
This kind of type identifies text generated by your PK-12. Examples include screen

Combinations of keystrokes are joined by a minus sign (–). For example, if you’re instructed to press
the Control (CTRL) key and the letter “Z” at the same time, the keystroke will be shown as
(CTRL-Z). Release all keys simultaneously.

WF7A).

menus, prompts, and error messages.

Key names like (ENTER), (RETURN), (SHIFT), (CTRL), and (SPACE BAR) mean press the key.
After entering any command into your PK-12, you’ll always press the (RETURN) or (ENTER) key.
So, whenever the word “enter” is used, it means to enter a command or text from your keyboard,
then press the (ENTER) or (RETURN) key. Throughout this manual, we’ll refer to this key as (RE­TURN).

viii / PK-12 Packet Controller Operating Manual

Abbreviations used throughout the manual

ack Acknowledge
call Call sign
CTRL Control
DCD Data Carrier Detect
ESC Escape
HF High Frequency
LF Line feed
mS Milli-second
n A variable which you substitute a number or letter
nack Not Ackno wledge
PTT Push-To-Talk

1. The PK-12

Overview

The PK-12 was designed to provide you with a superior packet operating platform when connected to
your computer and a VHF or UHF transceiver.

Capabilities & Features

• AX.25 levels 1 & 2, 1200 bps packet operation in the Command, Host and KISS modes.

• 32K MailDrop RAM (expandable to 128K RAM with upgrade option, see Appendix E).

• Gateway for node operation.

• GPS firmware which is remotely programmable, can be remotely polled, and is compatible with GPS,
Loran, ARNAV, and Ultimeter II. Optional APRS Adapter Cable available. The GPS firmware also
allows for Stand Alone Tracking and automatically detects GPS receivers at power-up.

• Terminal software and GPS tracking/mapping software included.

• Compatible with many terminal control programs including Timewave’s PC PakRatt II and PC PakRatt
for Windows 2.0.

• DAMA support for master/slave node communication.

• Uses little power and can run even run on a 9-volt battery.

• Enhanced MHEARD function identifies TCP/IP, NET/ROM, and <The-Net> stations.

• Special commands (DFROM, CFROM) commands that let you control who connects to your TNC.

• EXPERT command included to ease the learning process—only the most common commands will be
usable until the EXPERT mode is enabled.

• Timewave/AEA’s expanded HOST mode.

• External AFSK adjustment, so there is no need to open the case.

• Limited one year warranty.

• Independent operation—once your PK-12 is up and running, you can turn off your computer or use it
to do something else; the PK-12 will independently accept connects, receive and forward mail, and act
as a node as long as power is supplied to it and your radio is on.

What You Should Have Received

Besides this manual, the following items are enclosed:

• A cable to connect your PK-12 to a radio.

• A power cable.

• A computer disk containing PK-Term for Windows and APRS sotware demo programs

Your Computer

You’ll need a computer or dumb terminal that has an RS-232 serial communications port so it can com­municate with your PK-12. If you plan to use a computer, you will need software that makes the com­puter act like a terminal. This is typically the same software you would use with a telephone modem.

For the sake of brevity in this manual, instead of using “dumb terminal” and “computer” interchangeably,
we’ll just use one word, “computer.”

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A Tour of the PK-12

Timewave

• XMT. This LED, when lit, indicates the transmitter is keyed.

• DCD. This LED, when lit, indicates the PK-12 hears data on the channel.

• CON. This LED, when lit, lets you know that you are connected to another packet station.

• STA. This LED, when lit, indicates unacknowledged messages or data in the transmit buffer.

• MAIL. This LED, when lit, lets you know that you have mail waiting in your MailDrop.

2. P o wer Suppl y &
Computer Installation

Overview

In this chapter, you’ll pow er up the PK-12 and connect it to the RS-232 serial port of your computer. Af­ter the connections have been made, you’ll do a quick check of the PK-12’s internal firmware and inter­nal modem by performing the all-important “loop-back” test. When you’v e completed this chapter, you’ll
be ready to connect the PK-12 to your transceiver and begin using it on the air.

Connecting Power

If you have a ready-made power supply like Timewave’s AC-1, connect it to the PK-12, plug the “power
cube” into the wall, and skip ahead to the Turning it On section.

PK-12 Packet Controller Operating Manual / 3

If you are not using a “power cube,” locate the power cable in the enclosed accessory bag and strip off
enough insulation from the ends of both conductors to connect it to your 12-14 VDC regulated power
supply.

Pay close attention to the polarity of the power cable—the positive (+) conductor is marked with a w hite
stripe.

Turning it On

With the power connections made, turn on the PK-12’s power supply (or plug the power cube into the
wall outlet), then press the POWER switch on the front of the PK-12. Watch closely for this start-up light
pattern: five LED’s—DCD, CON, STA, MAIL, and POWER—should light. If this occurs, then switch
off the PK-12 and move on to the section, Connecting Your Computer to the PK-12.

If none of the red LED’s ar e lit upon power-up but the green POWER light is on, then the controller has
been previously initialized and set to your computer’s current TBAUD speed—it has already passed the
autobaud routine, which will be described shortly.

If either of the above doesn’t happen, go to Chapter 7 - Troubleshooting.

Re-Initialization

If the PK-12 has been previously initialized, it’s ready to communicate with a computer at a baud rate of
300, 1200, 2400, 4800 or 9600 baud. If you’re new to TNC operation, we suggest you r e-initialize the
PK-12 now so you’ll have an easier time getting it up and running later. Reinitializing the controller will

make it “forget” all of its user-defined parameters and will return it to its default settings from the
factory.

To re-initialize the PK-12, enter RESET after the cmd: prompt.

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Connecting Your Computer to the PK-12

NOTE:

Make sure that the PK-12 and computer are turned off before proceeding.

The Cable

For communication to take place between your computer and the PK-12, you need a properly wired
shielded cable that will connect the computer’s serial port to the RS-232 I/O port on the back of the PK-

12.
The style of connector you have on your computer probably looks like one of these three:

Here’s a table of pin assignments to wire the PK-12’s RS-232 I/O port to a typical computer’s serial port:

from PK-12 to... Macintosh
RS-232 I/O DB-25F DB-9 mini DIN-8P Function

8 8 1 2 (DCD)
3 3 2 5 (RxD)
2 2 3 3 (TxD)
20 20 4 1 (DTR)
7 7 5 4+8 (GROUND)
6 6 6 (DSR)
4 4 7 (R TS)
5 5 8 (CTS)
1 1 Shield

Don’t use a “null modem” cable. This type of cable flips pins 2 & 3 so that pin 2 on one end of the cable
is connected to pin 3 on the other end (and vice versa). Use a cable that has “straight through” connec­tions like the ones used to connect computers to a telephone modem, since as far as your computer is con­cerned, the PK-12 is a modem.

If you’re using a computer that has a DB-9 connector for its serial port, you can purchase an adapter from
Radio Shack that will work with the supplied computer cable.

Once you’ve tested the cable to make sure it’s pinned correctly, plug one end into your computer’s serial
port and the other end to the RS-232 I/O port on the back of the PK-12. Then, proceed to the System
Start-up and Loop-back Test section in this chapter.

Dumb Terminals

If you have an RS-232 dumb terminal, you may need to change the gender of the cable provided with
your PK-12. This can be done with an inexpensive double-male RS-232 gender changing adapter avail­able from Radio Shack and other computer dealers. The Radio Shack part number is 26-243.

The Computer

If the type of computer you plan to use with the PK-12 wasn’t mentioned earlier in this chapter, you may
find specific connection information below. You’ll also need a communications program to use with your
computer. See The Software section following this one for information regarding communication pro-
grams for many of the above machines.

Computers that don’t have a serial port or permit use of a suitable adapter or level converter can’t be used
with the PK-12.

Other Computers with RS-232 Ports

If your computer has an RS-232 port, consult your computer manuals to see which pins are used for TxD,
RxD, and signal ground. Read the manufacturer’s recommendations for connecting the serial port to a
telephone modem. Connect your PK-12 the same way.

The PK-12 is configured as Data Communications Equipment (DCE)—it receives data on pin-2. Most
computers and terminals are configured as Data Terminal Equipment (DTE) transmitting data on pin-2.

If your computer is configured as DTE, use the supplied RS-232 cable with a gender changing adapter, if
necessary. These are available from Radio Shack (catalog# 26-243) and other computer stores.

PK-12 Packet Controller Operating Manual / 5

If your computer is configured as DCE, wire it like this:

• Wire pin 2 of the PK-12 to pin 3 of the RS-232 computer connector.

• Wire pin 2 of the computer’s RS-232 connector to pin 3 of the PK-12.

• Wire pin 7 to pin 7.

Other Computers with Non-Standard Serial Ports

Computers with non-standard serial ports must meet the following conditions:

• The signal levels must be compatible with RS-232C. The PK-12 requires the voltage levels from the
computer to be greater than +3 volts in the “asserted” state and 0 volts or less in the “non-asserted” state.

• The signal polarity must conform to the RS-232C standard. The 0 or negative-voltage state must
correspond to logical “1” and the positive-voltage state to logical “0.”

Make or buy a cable that provides the following connections:

• The computer’s serial port signal ground or common pin must be connected to the PK-12’s serial port
connector, pin 7.

• The pin on which the computer sends data (TxD) must be connected to the PK-12’s RS-232 connector,
pin 2.

• The pin on which the computer receives data (RxD) must be connected to the PK-12’s RS-232
connector, pin 3.

If your computer requires any other signals, you must arrange to provide them. The PK-12 has the stan­dard hardware handshake lines available. As a default, the PK-12 provides XON/XOFF software flow
control to the computer or terminal. The command, XFLOW, can be turned off, disabling software flow
control and enabling hardware handshake if your computer requires it. Hardware flow control is achieved
with RTS/CTS (pins 4 and 5) of the DB-25 RS-232 I/O connector. The documentation provided with
your computer or serial card should clarify any special requirements.

6 / PK-12 Packet Controller Operating Manual

The Software

If you’re going to use your PK-12 with a computer, you’ll need to read parts of this section to set up your
communications or terminal (modem) program software. If you’ll be using your PK-12 with a dumb ter­minal, you won’t need any software and can skip to the next section, System Start-up and Loop-back
Test.

The PK-12 operates in much the same manner as a telephone modem, so most telephone modem termi­nal programs will work with your PK-12. Some of these programs are in the “public domain,” which
means they’re free. Other terminal programs are “share-ware,” which means you may get them from a
friend and try them before you buy them. Of course, you can always purchase a program outright from
Timewave, a local amateur radio dealer, a nearby computer dealer, or through mail-order software
houses.

Follow the installation directions for the terminal program you plan to use. Once installed on your com­puter, you should start the program and set its parameters to:

• Data Rate = 9600 bits per second (Baud)

• Data bits/word length = 8

• Parity = NONE

• Stop bits = 1

• Duplex = FULL

• Handshake = XON/OFF

As a default, the PK-12 provides XON/XOFF software flow-control to the computer or terminal. The PK­12 command, XFLOW, can be turned off to disable software flow control and enable hardware hand­shake if your computer requires it. Hardware flow control is achieved with RTS/CTS (pins 4 and 5) of the
DB-25 RS-232 I/O connector.

Installing PC PakRatt Lite

You will need 500K of free hard disk space to load PC PakRatt Lite

1. Insert the installation disk into the floppy drive on your computer, A: or B:.

2. If you placed the disk in drive A:, type: A:INSTPPLT and then press ENTER.
If you placed the disk in drive B:, type: B:INSTPPLT and press ENTER.
This brings up a screen that explains what you need to do to install PC PakRatt Lite. Follow the di-

rections and PC PakRatt Lite will load itself on your hard drive.

3. After installation, it is highly recommended that you print the PC PakRatt Lite Operating Manual.
The manual is copied to the PC PakRatt Lite drive and the directory when the program is installed.

NOTE:

NOTE:

The manual uses about 60 pages when printed. To print the manual, type: cd\PPLITE at the C: and
press ENTER; this puts you in the PC PakRatt Lite directory. Now type: COPY
PPLITMAN.PRN LPT1 (or LPT2, 3, or 4 — whichever your printer is connected to) and press
ENTER. The manual should begin printing.

The manual can be viewed on your screen using a text editor, however we recommend printing the
manual on your printer.

4. After printing the manual, read through the setup instructions to find out how to properly config­ure the program and TNC.

5. To run the program type: cd\PPLITE at the C: and press ENTER. You will see this: C:\PPLITE>.
Now type: PPLITE and press ENTER.

You are ready to setup and use PC PakRatt Lite.s

System Star t-up and Loop-back Test

Make sure that you’ve connected your PK-12 to a power supply and to the RS-232 port of your com­puter or terminal.

1. Don’t connect any other cables to your radio yet!

2. With wire strippers and radio cable in hand, remove about an inch (2.5cm) of cable jacket, expos­ing the five colored wires and the shield-wire. Be careful not to nick the wires’ insulation.

3. Strip about 1/4 inch (7mm) of insulation from the green and white wires and short them by gently
twisting their stripped ends together.

4. Plug the cable into the RADIO socket on the PK-12’s rear panel.

5. Set the TX LEVEL pot on the rear of the PK-12 to 50% rotation (straight up and down) using a
small screwdriver.

6. Turn on your computer. Load your communications program. (Choose the TTY option, if avail­able.)

PK-12 Packet Controller Operating Manual / 7

NOTE:

If you’re using an Timewave program, follow its manual’s instructions for TNC start-up, then skip to Step

9.

7. Press the PK-12’s power switch to the ON position.

8. Type an asterisk (*). The PK-12 will automatically try to recognize your computer’s data (baud)
rate that’s set in the communications program you’re using—this is referred to as the autobaud rou­tine. When the PK-12’s baud rate matches your computer’s baud rate, your screen will display the
following sign-on message:

AEA PK-12 Packet Controller
AX.25 Level 2 Version 2.0
Copyright (C) 1995 by
Advanced Electronic Applications, Inc.
Release 26.JUN.95
Ver. 7.1
cmd:

The five red LED’s on the front panel should now be off.
(Make note on the first page of this manual of the firmware release . This is important should you

ever need to call Timewave for technical support.)

8 / PK-12 Packet Controller Operating Manual

bar once, enter the command’s “argument” (the variable or text you’re changing) if appropriate,
then press (RETURN).

9. For now, enter a mock call sign after the cmd: prompt. For example:
MYCALL AAA
After you’ve entered this, the PK-12 will print the following on the screen:

MYcall was PK12
MYcall now AAA

10. The PK-12 recognizes the letter “C” to mean “connect to...”. Try to connect to yourself by entering:
C AAA
After a few moments, your monitor should display:

*** CONNECTED to AAA

11. Type Hi, there!, then press (RETURN). Your monitor should echo the same message.

12. Press (CTRL-C)—you’ll get the cmd: prompt back. Enter the letter “D” so you can disconnect
from yourself. You should get the message:

*** DISCONNECTED: AAA
cmd:

If you’ve gotten this far, the PK-12 is operating properly. If you’re having difficulties, see Chapter 8 ­Troubleshooting.

If you experienced problems with the above procedure, go back to Step 1 after checking all the cables
and connectors for proper wiring, continuity, and connection. Read each step again carefully. The most
common errors made during this procedure are: trying to connect to a call sign different from the one you
entered after MYCALL, not having the green-and-white wires shorted, or not setting the TX LEVEL to
50% rotation.

3. Radio Installation

Overview

This chapter describes how to connect the PK-12 to your radio receiver or transceiver.

To Transmit and Receive. . .

If you want to transmit as well as receive, you’ll need to make the proper connections to your radio’s
speaker, microphone, ground, and the Push-To-Talk (PTT) circuits.

The best way to connect the PK-12 to your transceiver is through its rear panel accessory port (if it has
one)—it will free up the mike jack so you don’t have to swap connectors with your mike and the PK-12.
If your radio doesn’t have an accessory port, use its microphone connector for your hookup.

NOTE:

If your controller is connected to your radio’s accessory port and you leave your mike plugged in, it will
cause your radio to transmit whatever it hears from the PK-12 if you accidentally key the mike.

PK-12 Packet Controller Operating Manual / 9

Radio Connection Requirements

Make sure that you remove power from your PK-12 and radio before making any of the following con­nections.

You’ll need the following items to make a radio cable to connect the PK-12 to your transceiver:

• The Timewave-supplied radio cable.

• A microphone or accessory-plug connector.

• A schematic of your radio’s microphone or accessory port.

• A low-wattage (under 40W) soldering iron and solder.

• Wire cutters or strippers.

NOTE:

10 / PK-12 Packet Controller Operating Manual

Basic Connections and Adjustments

The following will help you identify the connection points to the PK-12’s radio ca ble:

Wire

Pin Signal Name Color Description

1 Microphone Audio White Transmit audio from the PK-12 to your transmitter
2 Ground Brown Audio and PTT common return
3 Push-To-Talk Red Keying line to your transmitter
4 Receive A udio Green Audio from your radio to the PK-12
5 Squelch Input Black Squelch input from radio (optional)
Shield/Drain Wire Silver Shield of cable / Microphone ground

Connections for Specific Transceivers

Appendix A contains notes and diagrams for connecting the PK-12 to many VHF/UHF transceivers. Lo­cate the transceiver you’ll be connecting to your PK-12. At the same time, refer to your radio’s Operating
Manual to verify the pin assignments. (If you don’t find your transceiver in Appendix A, locate a model
from the same manufacturer that has the same accessory or mike connector and pinouts as the unit you’ll
be connecting—usually the manufacturer is consistent with their wiring formats so the hookups will be
the same.)

If you’ll be using a packet channel that’s shared with voice users, you should connect the black wire to
the Squelch pin of the connector—this will prevent the PK-12 from transmitting when there’s a received
signal strong enough to open the squelch. If you connect this pin, you may have to change the
SQUELCH setting in the PK-12. (Most VHF/UHF Pac ket operations are no longer shared with voice re­peaters, so this generally isn’t used.)

So, to fashion the radio cable:

1. Locate the radio cables included with your PK-12.

2. Prepare the bare end by removing an appropriate amount of jacket for the mike connector you’ll at­tach. Typically, this is .5 - .75 inches.

3. Carefully remove the foil shield exposing the colored wires underneath. Be careful not to nick or
cut the shield wire.

4. Strip back about .125 inch of colored insulation from the red, white and brown wires. Don’t strip
back the black wire if you don’t intend to use it—just cut it short.

5. Feed the connector’s backshell over the cable end, then look at the connector closely to locate Pin

1. Compare this to the location of Pin 1 on the connector drawing in your transceiver’s manual and
the one in Appendix A. This is important, as some diagrams show the connector from the inside of

the transceiver, not the outside of the plug you are wiring. This will help insure that the plug is not
wired backwards.

6. Warm up your soldering iron and begin soldering the wires.

When wiring a connector, it’s often easier to wire the inside or middle pins first, then work your way
to the outside pins.

7. Connect the Shield (silver) wire to the mike’s ground connection, if your transceiver has one. If it
doesn’t have a separate mike or ground connection, then connect it to the single ground along with
the brown wire. (See the next step.)

8. Connect the brown wire to the main ground on the connector. This ground is the one used for the
PTT and receive audio. You should connect the silver Shield/Drain wire to this ground only if there
isn’t a separate mike ground as described in the previous step.

If you’re connecting a handheld (“handy-talkie”) transceiver to your PK-12, you’ll pr obably need a resis­tor and/or capacitor to isolate this connection from the AFSK audio (check Appendix A).

Transceiver Adjustments

PK-12 Packet Controller Operating Manual / 11

NOTE:

Make sure your PK-12 and radio are turned off and all the cables are correctly wired and connected.

1. Connect a dummy load to your radio and be prepared to monitor your transmissions with a devia­tion meter.

NOTE:

If you don’t have a deviation meter, a “quick ’n’ dirty” way to set the 1200 bps AFSK level is to turn the
TX LEVEL pot on the back of the PK-12 halfway between its stops.

2. Verify that your PK-12 and FM radio are connected as shown in the following figure:

12 / PK-12 Packet Controller Operating Manual

3. Turn on your radio and computer.

4. Go ahead and load your terminal program so that you’re operating the PK-12 in the Dumb Termi­nal mode.

5. Enter the CALIBRATE mode by entering: CAL next to the cmd: prompt.
In the CALIBRATE mode only, the letter K toggles the transmitter PTT line on and off; the

(SPACE) bar toggles the tone generator from Mark (the lower pitched tone) to Space (the higher
pitched tone).

The PK-12 has a transmit watchdog timer circuit that unkeys your transmitter automatically after
sixty (60) seconds.

6. Press K to key the transmitter.

7. Tap the (SPACE) bar several times until the higher pitched of the two tones (Space) is heard.

8. Adjust the transmit audio level by adjusting the rear-panel TX LEVEL pot clockwise until the de­viation meter reads ±3 kHz average deviation. If 3 kHz can’t be obtained, change the position of
JP3 and repeat adjustment.

9. Press K to return to receive mode.

10. Press Q to leave the CALIBRATE mode.

11. Set your receiver’s squelch control for normal voice operation.

NOTE:

PK-12 Packet Controller Operating Manual / 13

4. You’re in Command

Overview

Most of the operating commands have a default value tha t provides good performance for the average
amateur radio statison, but there’s no rule that says you must keep these defaults. You can change the de­fault values as required for your individual operating needs, type of equipment, and local operating prac­tices or protocols.

Don’t be intimidated by all the commands that are available to you—an average user needs to understand
or change only a handful of them. Once set, they usually don’t need to be reckoned with again. (See EX­PERT.) This chapter is intended as a command and error message reference and is not meant to be read
from start to finish.

Parameters and Arguments

If a command requires an argument, the type of argument is indicated after the command name as well as
its default value. There are three different types of parameters used: Boolean, Numeric (or Text), and
String.

Boolean

Boolean arguments use one value out of a choice of only two possible v alues, such as ON or OFF, YES or
NO, or EVERY or AFTER. Boolean arguments can also be changed back and forth (toggled) with an ar­gument of TOGGLE or T.

Numeric

An argument designated as “n” is a numeric value. Numeric values can be entered by typing them in fa-
miliar decimal numbers, or in hexadecimal numbers. When using hexadecimal notation, you must type a
$ in front of the number to tell the PK-12 that this is a “hex” number.

For numeric parameters, the arguments ON or Y set the parameter v alue to its default. Arguments OFF or
N set the value to zero. Baud-rate parameters can use arguments UP (U) or DOWN (D) to select the next
higher or lower baud rate.

Text or String Arguments

A text parameter, such as the CTEXT message, can hold almost any ASCII character, including upper­case and lowercase letters, numbers, spaces, and punctuation.

Some commands, such as CONNECT, require call signs as arguments. These arguments are usually call
signs, but may be any string of up to six characters with at least one letter. Some commands, such as
CFROM, have arguments which are actually lists of call signs. You must separate multiple call signs with
either spaces or commas.

14 / PK-12 Packet Controller Operating Manual

Changing Commands

As you skim through the list of commands, you’ll notice that the first few characters in the command are
capitalized and the rest aren’t. The capitalized letters are a shorthand way of entering a command and are
the minimum number of characters you need to type in to use that command. For example, with the com­mand DISPlay, you can enter DISP, DISPL, DISPLA and DISPLAY and all these entries will work. You
can also enter commands using lowercase, uppercase, or a combination of lowercase and uppercase let­ters.

When you change a command’s value, the PK-12 will let you know a change has been made and the
change will be automatically saved. Say you want to enter your call sign. If your call sign is WF7A, then
this is what you’ll type:

cmd: MY WF7A
MYcall: was PK12
MYcall: now WF7A
cmd:

If you turn off or remove the power cord from your PK-12, it will remember the change(s) you’ve made
provided you haven’t removed the PK-12’s internal jumper, JP-1. Also, all commands that accept values
or parameters may be typed without any arguments to check their present setting.

If, while changing timing commands and such, you find that you’ve “dug yourself into a hole” and the
PK-12 doesn’t work as well as it did before, enter REINIT—it will reinitialize most of the commands to
their default settings and perform a RESTART, but it won’t lose the contents of the MailDrop. (Contrary
to this, if you enter RESET, you’ll return the PK-12 back to its factory default settings, lose any stored
mail messages, and you’ll have to go through the autobaud routine again.)

List of Commands

Commands are listed alphabetically with their descriptions. Each command entry contains several fields
of information: Command Name, Default Value, and operational description. The default value is listed
first.

3Rdparty

With 3RDPARTY OFF, the MailDrop system will only allow messages to be addressed to you. Turning
3RDPARTY ON informs the MailDrop system to allow messages to be addressed to anyone.

8Bitconv

8BITCONV ON permits transmission of 8-bit data in Converse mode. When 8BITCONV is OFF, bit 7
of characters received from the terminal is set to 0 (zero) before the characters are transmitted.

ON|OFF

ON|OFF

Default: OFF

Default: OFF

ACKprior

This command implements the Priority acknowledge scheme described by Eric Gustafson, N7CL, which
proposes to improve multiple-access packet performance on VHF simplex channels with “hidden” termi­nals. When a busy channel clears, the ackno wledgments are sent immediately, while data and poll bits are
held off long enough to prevent collisions with the ack packets. By giving priority to data acks, fewer
acks will collide with other station’s data, reducing retries. Digipeated frames are sent immediately.
RAWHDLC and KISS force ACKPRIOR OFF.

ON|OFF

Default: OFF

PK-12 Packet Controller Operating Manual / 15

These are the defaults for a P-persistence system with no Priority acknowledgment: ACKPRIOR OFF,
PPERSIST ON, PERSIST 63, SLOTTIME 30, RESPTIME 0, MAXFRAME 4, and FRACK 5.

The following are the recommended command settings for Priority acknowledge:
ACKPRIOR ON

PPERSIST ON
PERSIST 84
SLOTTIME 30
RESPTIME 0
MAXFRAME 1 - 7
FRACK 8
DWAIT - doesn’t matter

Stations using neither the Priority acknowledge nor the P-persistence schemes should set DWAIT 73. Sta­tions using P-persistence, but not Priority acknowledge should set PERSIST and SLOTTIME to the same
values that ACKPRIOR stations are using.

Timewave and TAPR use some different command names to handle P-persistence. The following table
should help with the Timewave/TAPR command differences:

TAPR MFJ Timewav e Remarks
Slots SLOTMASK PERSIST

1 $00 255 Disables slotting
2 $01 127
384
4 $03 63 Default setting
642
8 $07 3 1 Very busy channel
12 20
16 $0F 15 Extremely busy channel
64 $3F 3

The TAPR DEADTIME command is similar to Timewave’s SLOTTIME command.

ACRDisp

n

This command allows you to customize the output of the TNC to meet your screen width. T he parameter
n tells the PK-12 how wide your screen is. The PK-12 will insert a carriage return and line feed after n
characters have been sent to your screen, making the display easier to read. Since computers and termi­nals do this automatically, you should only change this parameter if your screen is hard to read.

ACRP ac k

ON|OFF

With A CRPACK ON, all packets sent in the Converse mode include the SENDPAC character, normally a
(RETURN), as the last character of the packet.

When ACRP A CK is OFF, the SENDP AC character is interpreted as a command, and isn’t included in the
packet or echoed to the terminal.

ACRPACK ON and SENDPAC $0D produce a natural conversational mode.

Default: 0

Default: ON

16 / PK-12 Packet Controller Operating Manual

AFilter

ON|OFF

Default: OFF

Some terminals and computers use special characters to clear the screen or perform other “special” func­tions. Since you did not type these characters, it is undesirable to send them over the air. Placing these
characters in the MFILTER list, and turning AFILTER ON, will keep the PK-12 from transmitting them.

Exception: when ECHO is ON and the computer sends a filtered character, the PK-12 will echo it back
to your terminal or computer.

AFILTER works regardless of mode, or CONNECT/CONVERSE/TRANSPARENT status. Leave
AFILTER OFF during binary file transfers.

ALFDisp

ON|OFF

Default: ON

ALFDISP controls the display of (RETURN) characters received, as well as the echoing of those that are
typed in.

With ALFDISP ON, the PK-12 adds a line feed (LF) to each (RETURN) it receives, if needed. If a LF
was received immediately before or after a (RETURN), ALFDISP won’t add another LF. Use the PK­12’s sign-on message to determine how (RETURN)’s are being displayed. (ALFDISP affects your dis­play, not transmitted data.)

• Turn ALFDISP ON if the PK-12’s sign-on message lines are typed over each other.

• Turn ALFDISP OFF if the PK-12’s sign-on message is double spaced.

• ALFDISP is set correctly if the PK-12’s sign-on message is single spaced.

ALFPack

ON|OFF

Default: OFF

ALFPACK is similar to ALFDISP, except that the LF characters are ad ded to outgoing packets rather
than to text displayed on your computer screen. If the person you’r e talking to reports overprinting of
packets from your station, set ALFPACK ON.

ALFPACK is disabled in the Transparent mode.

AUdela y

n

Default: 2 (20 mS)

Some synthesized transceivers may produce undesirable spurious emissions if the modem tones and PTT
are applied at the same time. AUDELAY allows you to reduce these emissions by inserting a delay be­tween the time PTT is asserted and the time the modem tones are transmitted. The parameter n specifies
the delay in increments of 10 milliseconds.

Please note that AUDELAY must always be less than TXDELAY. It’s advisable that AUDELAY be set
lower than TXDELAY by a setting of 10.

AUTOBaud ON|

OFF

Default: OFF

With AUTOBAUD OFF, the PK-12 will automatically determine the terminal baud rate only when pow­ering-up for the first time (right out of the box) or after a RESET. With AUTOBAUD ON, the PK-12 de­termines the terminal baud rate every time it’s powered-up, and every time the RESTART command is
entered. Setting AUTOBAUD ON is helpful when moving the unit from one computer to another where
the terminal data rates are different.

When the PK-12 is trying to determine the terminal baud rate, it will send a message to the terminal ask­ing you to enter a ‘*’. You will most likely not be able to read the message; it will appear as junk charac­ters if the PK-12 is using a different baud rate than your terminal is. Simply press the ‘*’ key to get the
PK-12 to change to the baud rate your terminal is set to.

PK-12 Packet Controller Operating Manual / 17

AWlen

n

Default: 7

In addition to the baud rate, the number of data bits used to send characters between your terminal and
the PK-12 must also be identical. Using this command, you can set the number of data bits to either 7 or
8 depending on your terminal’s requirements. AWLEN will most likely be set properly by the PK-12’s
autobaud routine.

For plain text conversations with the PK-12, AWLEN 7 or 8 may be used. For binary file transfers and
Host mode operation, AWLEN 8 must be used.

The RESTART command must be issued before this command takes effect.

Ax25l2v2 ON|

OFF

Default: ON (v2.0)

This command allows the selection of either the old (ver. 1) version of the AX.25 packet protocol or the
current (ver . 2.0) protocol. Some implementations of v e rsion 1 of AX.25 protocol won’t properly digipeat
version 2.0 AX.25 packets. Most users run AX.25 version 2, but this command allows you to return to the
older version, if necessary, f or compatibility.

AXDelay

n

Default: 0 (00 mS)

“n” 0 to 180 specifies a key-up delay for voice repeater operation in 10 mS intervals.
AXDELAY specifies the period of time the PK-12 will wait—in addition to the delay set by

TXDELAY—after keying the transmitter and before data is sent. Packet groups using a standard voice
repeater to extend the range of the local area network may need to use this feature.

Repeaters with slow electromechanical relays, auxiliary links, or other circuits which delay transmission
after the RF carrier is present require more time to get RF on the air. Try various values to find the best
value for “n” if you’re using a repeater that hasn’t been used for packet operations before. If other packet
stations have been using the repeater, check with them for the proper setting. AXDELAY acts together
with AXHANG.

AXHang

n

Default 0 (000 mS)

“n” 0 to 20 specifies voice repeater “hang time” in 100 mS intervals.
AXHANG allows you to increase efficiency when sending packets through a repeater that has a hang

time greater than 100mS. When the PK-12 hears a packet sent within the AXHANG period, it doesn’t
add the repeater key-up delay (AXDELAY) to the key-up time. Try various values to find the best value
if you’re using a repeater that hasn’t been used for packet operations before. If other packet stations have
been using the repeater, check with them for the proper setting.

BBSmsgs ON|

OFF

Default: OFF

ON - Makes the PK-12 status message look like TAPR-style output.
OFF - The PK-12 status message will work as before (default).

When BBSMSGS is ON, some of the status messages change or are suppressed which may improve op­eration of the PK-12 with some BBS software. The following Timewave PK-12 status messages are sup­pressed or changed if BBSMSGS is ON:

No “(parm) was (value)”
No “(parm) now (value)”
Connect messages: No “; v2; 1 unACKed”

18 / PK-12 Packet Controller Operating Manual

No “xxx in progress: (dest) via (digis)”
No space after comma in digipeater lists
“Via” in upper case
If MRPT is ON, digi paths are displayed in TAPR format
No “*** connect request:”
No “*** retry count exceeded”
Sends carriage return before all other “***”
No “(callsign) busy” message

Beacon

EVERY|AFTER n

Default:

EVERY 0

(00 sec.)

The PK-12 may be programmed to send a message (‘beacon’) at some pre-determined interval. The bea­con message is set using the BTEXT command. The beacon’s address is set using the UNPROTO com­mand. When the argument EVER Y is specified, a beacon packet is sent every “n” x 10 seconds. When
AFTER is specified, a beacon is sent after (n x 10) seconds have passed without any packet activity being
heard. The parameter n may be set from 0 (no beacon) to 250 (2500 seconds, or 40 minutes) in 10 sec­ond increments.

If you set BEACON to less than 9 —a value judged as too short for busy channels—you’ll see the fol­lowing message at each command prompt: WARNING: BEACON too often

BKondel ON|

OFF

Default: ON

This command determines what the PK-12 sends to your terminal each time the delete key is pressed.
When ON, the PK-12 sends the sequence backspace - space - backspace to the terminal removing the last
character you typed. When OFF, the PK-12 sends a backslash (\) to your terminal each time the delete
key is pressed. You can get a display of the corrected input by typing the REDISPLAY-line character.

BText

text

Default: empty

This command is used to enter a message (up to 120 characters) to be sent during beacon operation. Use
%, &, N, NO, NONE,or OFF as arguments after you enter BTEXT on the command line to clear text you
previously typed in for that command. Don’t enter your call sign as part of the beacon text, it is part of
the packet frame and will be sent anyway.

CALibrate

CALIBRATE is used during installation to set the transmitted audio level. The TX LEVEL pot on the
back of the PK-12 is used to set the proper audio level (see Installation section).

When in CALIBRATE mode, all packet connections will be lost and the time-of-day clock will not ad­vance until you exit. Commands available in the CALIBRATE routine are:

K Toggles the PK-12’s PTT circuit on and off.
Q Quits the calibration routine.

The PK-12 has a timer circuit that will automatically shut off the transmitter after it has been on for sixty
seconds.

PK-12 Packet Controller Operating Manual / 19

CANline

n

Default: $18 (CTRL-X)

Any time you have entered a line of text and not yet pressed the (RETURN) key, the line can be can­celled by pressing and holding the (CTRL) key while pressing the key specified b y CANLINE. Any
ASCII character from 0 to 127 may be used to cancel a line.

Note: If your SENDPAC character isn’t (RETURN), the CANLINE character cancels only the last line
of a multi-line packet.

CANPac

n

Default: $19 (CTRL-Y)

Any packet message that has been typed in prior to typing the SENDPAC character may be cancelled by
pressing and holding CTRL while pressing the key specified by CANPAC. Any ASCII character from 0
to 127 may be used to cancel packet messages.

You can only cancel the packet that’s currently being entered in the Converse mode. When you cancel a
packet, the line is terminated with a ( \ ) and your cursor is put on a new line.

In the Command mode, this character cancels all the output from the PK-12 to your computer screen. En­tering the CANPAC character again restores normal output from your PK-12.

CASedisp

n

Default: 0 (as is)

Use this command to set the case used to send characters to your terminal. Setting CASEDISP to 0 turns
off case changing; characters are displayed as they are received. Setting CASEDISP to 1 causes all char­acters to be displayed in lower case, setting CASEDISP to 2 causes all characters to be displayed in upper
case.

CBell ON|

OFF

Default: OFF

CBELL ON causes the PK-12 to send three bell characters (CTRL-G) to your terminal when the con­nected or disconnected messages are displayed. Setting CBELL ON, will let you know when someone
has connected or disconnected from your TNC.

CFrom

ALL, NONE, YES/NO call1,call2...

Default: ALL

CFROM determines how y our PK-12 r esponds to connect requests fr om other stations. CFROM is set to
ALL when you first start your PK-12. This means your PK-12 will respond to all the connect requests ad­dressed to it.

To reject all connect requests, type CFROM NONE. Your PK-12 sends the calling station a “busy signal.”
(This is like leaving your telephone off the hook.)

To accept calls from one or mor e specific stations, type CFROM YES followed by a list of call signs.
Connect requests will be accepted from stations whose call signs are listed after CFROM YES. Similarly,
to reject calls from one or more specific stations, type CFROM NO followed by a list of call signs. You
can include optional SSIDs specified as “-n” after the call sign. With CFROM NO KB6IUX, connect at-
tempts from all SSIDs of KB6IUX (KB6IUX-0 through KB6IUX-15) will be ignored. If CFROM is set
to YES KB6IUX-1, then only KB6IUX-1 will be allowed to connect to you.

Clear CFROM with %, &, or OFF as arguments.

20 / PK-12 Packet Controller Operating Manual

CHCall ON|

OFF

Default:OFF

With CHCALL ON, the call sign of the originating station appears after the channel identifier even if
you’re connected through more than one packet station. With CHCALL OFF, only the channel number is
displayed in a single or multiple-connection operation.

CHDouble ON|

OFF

Default: OFF

Set CHDOUBLE ON when operating with multiple connections to tell the difference between
CHSWITCH characters received from other stations and CHSWITCH characters generated by your PK-

12. In the following example CHDOUBLE is ON and CHSWITCH is set to “|” ($7C): || this is a

test.
The sending station actually transmitted: | this is a test.
The same packet received with CHDOUBLE OFF would be displayed as: | this is a test.

CHeck

n

Default: 30 (300 sec.)

Without the CHECK feature, if your PK-12 were connected to another station and the other station disap­peared, your PK-12 would remain connected indefinitely, perha ps refusing connections from other sta­tions. Y our PK-12 tries to prevent this from occurring—depending on the settings of AX25L2V2 and RE­CONNECT—by using the CHECK timer as follows:

• If a Version 1 link is inactive for CHECK x 10 seconds, your PK-12 tries to save the link by starting a

reconnect sequence. The PK-12 enters the “connect in progress” state and sends “connect request”
frames.

• If a Version 2 link (AX25L2V2 ON) is inactive and packets haven’t been heard from the other station

for “n” x 10 seconds, your PK-12 sends a “check packet” to test if the link still exists. If your PK-12
doesn’t get an answer to the “check packet” after RETRY+1 attempts, it will attempt to reconnect to the
other station.

See the RELINK command.

CHSwitch

n

Default:$00

If you plan to engage in multiple packet connections, you must select a CHSWITCH (Channel
SWITCH) character. T his character will be interpreted by the PK-12 to indicate that you want to select
another packet channel.

CHSWITCH selects the character used by both you and the PK-12 to show that a new connection chan­nel is being addressed. DO NOT USE $30 to $39 (0 to 9).

The vertical bar “|” ($7C) is a seldom used punctuation mark and makes a good switching character. To
make the CHSWITCH character the vertical bar, simply enter the command and the ver tical bar’s ASCII
code: CHSWITCH $7C.

To change packet channels, simply type the vertical bar “|” followed by a number between 0 through 9,
indicating which channel you want to use. So, to go from Channel 0 to Channel 1, you’d enter:

cmd:|1
See CHDOUBLE and CHCALL for further information on the use of CHSWITCH.

PK-12 Packet Controller Operating Manual / 21

CMdtime

n

Default: 10 (1000 mS)

The PK-12 has a mode which allows it to send raw data without interpreting control sequences (special
characters) in the data stream; this mode is called ‘transparent’ mode. When the PK-12 is in transparent
mode, there doesn’t appear to be any way to return it to the cmd: prompt (command mode). To leave the
transparent mode, the COMMAND character (CTRL-C default) must be entered three times within the
period of time set by CMDTIME (defaults to 1 second). This is done purposely to reduce the chance that
transmitted data could pop the PK-12 out of transparent mode.

CMDTIME is adjustable from 0 to 250 (0 to 25 seconds) in 100 millisecond increments.

CMSg ON|

OFF

Default: OFF

CMSG enables or disables automatic transmission of the CTEXT message when your PK-12 accepts a
connect request. Set CMSG ON to send the connecting station your CTEXT message. One idea is to put
an invitation for the connecting station to leave a message in your MailDrop if you’re not available in
your CTEXT message.

CODe

n

Default: 0 (Square Brackets)

“n” 0 to 6 specifies a code from the list below. (RX = Receive; TX = Transmit)
CODE is used to change the way the PK-12 displays square brackets (ASCII $5B, $5D) in packet head-

ers and MailDrop prompts. Setting CODE to 0 allows the use of square brackets, while setting CODE to
6 changes all square bracket use to parenthesis. US ASCII square bracket characters are used as extended
alphabetic characters in most languages outside of English.

COMmand

n

Default: $03 (CTRL-C)

COMMAND changes the Command mode entry character. Type the COMMAND character once to re­turn to Command mode from Converse mode, or three times to return from Transparent mode. After you
enter the COMMAND character, the Command prompt (cmd:) should appear, indicating successful en­try into the Command mode. See CMDTIME for more information. COMMAND may be set to any
ASCII character from 0 to 127.

CONmode

CONVERSE|TRANS

Default: CONVERSE

CONMODE is used to instruct the PK-12 to either enter the converse mode or the transparent mode after
connection is established. This parameter should rarely need to be changed.

CONNECT call1 (Via call2,call3,...call9)

Use the CONNECT command to send a packet connect request to station call1, directly or VIA (through)
one or more “digipeaters” (call2 through call9). Each call sign can include an optional SSID-n immedi­ately after the call sign.

For example, say you want to digipeat through two stations that are on a linear radio path to the third sta­tion, the one you want to talk to. You’d type something like this after the cmd: prompt:

C WF7A V KG6ZL,KB6IUX-1,WO6P
This string means that you want to CONNECT to WF7A Via (through) station KG6ZL, then KB6IUX-1,

then WO6P. The path looks like this:
You ➔ KG6ZL ➔ KB6IUX-1 ➔ WO6P ➔ WF7A

22 / PK-12 Packet Controller Operating Manual

You can type CONNECT (without any parameters) at any time to check the PK-12’s connect status. If
you’re in the process of trying to connect to another station, you’ll see the message:

Link state is: CONNECT in progress

If the other station doesn’t ack your connect request after the number of tries set with RETRY, the con­nect attempt is cancelled. Your monitor would display:

cmd:*** Retry count exceeded
*** DISCONNECTED:

call1

CONOK ON|

OFF

Default: ON

ON - Connect requests from other stations will be accepted if CFROM is set to ALL.
OFF - Connect requests from other stations will not be accepted if CFROM is set to ALL or NONE.

CONOK is included only to maintain upward compatibility with the TAPR TNCs and some BBS soft­ware that depend on this command being there. The command CFROM is much more versatile, and
should be used instead of CONOK.

Make sure that CFROM is set to ALL if your software needs CONOK.

CONPerm ON|

OFF

Default: OFF

CONPERM allows you to establish a permanent connection with another TNC. When CONPERM is
ON, the PK-12 is forced to maintain the current connection, even when the number of frames to the other
station exceeds RETRY attempts for an acknowledgment. For standard packet use, CONPERM should
remain OFF.

CONStamp ON|

OFF

Default: OFF

CONSTAMP is used to activate time stamping of *** CONNECTED status messages. If CONSTAMP is
ON and DAYTIME (the PK-12’s inter nal clock) is set, the time is sent with CONNECT and DISCON­NECT messages. For example, if the clock is set and CONSTAMP is ON, a connect and disconnect se­quence would appear like this:

cmd:10:55:23*** CONNECTED to KB6IUX
cmd:10:55:59*** DISCONNECTED: KB6IUX

CONVerse ( or K)

CONVERSE is an immediate command that causes the PK-12 to switch from the Command mode to the
Converse mode. The letter “K” may also be used.

Once the PK-12 is in the Converse mode, all the characters typed into the keyboar d are transmitted by
your radio. To return the PK-12 to the Command mode, type the Command mode entry character,
(CTRL-C).

CPactime ON|

OFF

CPACTIME activates automatic, periodic packet transmission in the Converse mode.
With CPACTIME ON, characters are “packetized” and transmitted periodically as if in Transparent

mode. Local keyboard editing and display features of the Converse mode are available. See the
PACTIME command for an explanation of periodic packetizing.

Default: OFF

PK-12 Packet Controller Operating Manual / 23

CStatus

SHORT

CSTATUS is an immediate command helpful in keeping track of your PK-12’s activity while singly or
multiply-connected to other stations. When CSTATUS is typed, your monitor displays the link status of
all ten channels as well as the current input/output channel as follows:

Not connected Connected to two stations

cmd:cs cmd:cs
Ch. 0 - IO DISCONNECTED Ch. 0 - IO CONNECTED to WF7A
Ch. 1 - DISCONNECTED Ch. 1 - CONNECTED to WF7A-1
Ch. 2 - DISCONNECTED Ch. 2 - DISCONNECTED
Ch. 3 - DISCONNECTED Ch. 3 - DISCONNECTED
Ch. 4 - DISCONNECTED Ch. 4 - DISCONNECTED
Ch. 5 - DISCONNECTED Ch. 5 - DISCONNECTED
Ch. 6 - DISCONNECTED Ch. 6 - DISCONNECTED
Ch. 7 - DISCONNECTED Ch. 7 - DISCONNECTED
Ch. 8 - DISCONNECTED Ch. 8 - DISCONNECTED
Ch. 9 - DISCONNECTED Ch. 9 - DISCONNECTED

CSTATUS will give a short display if desired. CSTATUS SHORT, or CS S, displays only the current in­put/output channel or those channels which are connected.

CText

text

Default: empty

CTEXT is the “answering machine” message sent when CMSG is ON. The message is sent only when
another station connects to you. You may enter any combination of up to 120 characters, including
spaces.

Clear CTEXT text by using the following arguments: %, &, NO, NONE, or OFF, or simply set CMSG
OFF.

CUstom

n

Default: $0A15

“n” 0 to $FFFF (0 to 65,535 decimal) specifies a four-digit hexadecimal value, where each bit con-

trols a different function described below.

CUSTOM was originally introduced to allow specialized features for custom applications to be added to
the PK-12 without burdening you with extra commands. Since the CUSTOM command is quickly filling
up, UBIT has been added to replace CUSTOM to allow for additional features. The CUSTOM command
is retained for compatibility, but we recommend using the UBIT command, as it’s more flexible and
easier to use.

For those applications that can’t take advantage of the UBIT command, the following CUSTOM features
are available in this release of the PK-12:

Bit 0, position $0001: If bit 0 is set to 1 (default), the PK-12 will discard a received packet if the

signal is too weak to light the DCD LED. If set to 0, packets will be re­ceived regardless of the carrier detector’s state.

Bit 1, position $0002: If bit 1 is set to 0 (default), then setting the MONITOR command to either

ON or YES will result in a MONITOR value of 4. If bit 1 is set to 1, then
MONITOR ON or YES will force the MONITOR value to 6.

Bit 2, position $0004: If bit 2 is set to 1 (default), a break on the RS-232 line will put the PK-12

into the Command mode (except from Host mode). If set to 0, a break on
the RS-232 line will not affect the PK-12.

24 / PK-12 Packet Controller Operating Manual

Bit 3, position $0008: If bit 3 is set to 0 (default), packet channel numbers will be numbered from

0-9. If bit 3 is set to 1, then packet channel numbers are labeled A-J or a-j.

Bit 4: Not used.
Bit 5, position $0020: If bit 5 is set to 0 (default) the PK-12 will always power up in the Com-

mand mode. If bit 5 is set to 1, then the PK-12 will remain in the previous
mode, that is, Converse, Command, or Transpar ent mode.

Bit 6, position $0040: If bit 6 is set to 0 (default), then monitoring is disabled in the Transparent

mode. If bit 6 is set to 1, then monitoring is active in the transparent mode.
MFROM, MTO, MRPT, MONITOR, MCON, MPROTO, MSTAMP,

CONSTAMP, and MBX are all active.
Bits 7-12: Not used.
Bit 13, position $2000: If bit 13 is set to 0 (default), MailDrop connect status messages are always

sent to the local user, reg ardless of the setting of MDMON. If bit 13 is set

to 1, remote user dialog and connect status messages with the MailDrop

are shown if MDMON is ON.
Bit 14, position $4000: If bit 14 is set to 0 (default), the transmit buffer for data sent from the com-

puter to the PK-12 in packet mode is limited only by the PK-12 memory. If

bit 14 is set to 1, the serial flow control will permit only a maximum of 7 I-

frames to be held by the PK-12 before transmission. This solves a problem

with the YAPP binary file transfer program, which relies on a small TNC

transmit buffer to operate correctly.
Bit 15: Unused at the present time.
To return CUSTOM to the default setting, type CU Y or CU ON at the command prompt.

DAYStamp ON|

OFF

Default: OFF

DAYSTAMP activates the date in CONSTAMP and MSTAMP. Set DAYSTAMP ON when you want a
dated record of packet channel activity, otherwise you will only get a time stamping on packet channel
activity.

DA ytime

date and time

Default: none

The clock isn’t set when the PK-12 is first turned on. The DAYTIME command displays the ?clock
not set error message until it’s set as follows:

YYMMDDHHMMSS

Example: cmd: daytime 940202065923
where: YY is the last two digits of the year 1995

MM is the two-digit month code (01-12) Feb
DD is date (01-31) 02
HH is the hour (00-23) 06
MM is the minutes after the hour (00-59) 59
SS is seconds (optional) 23

If you want the PK-12 to keep current time, either keep its power supply on, have the software you’re us­ing set the clock upon start-up, or install a dedicated clock chip. The clock chip of choice is the
SmartWatch clock chip (DS1216C) by Dallas Semiconductor, which may be obtained through them at

PK-12 Packet Controller Operating Manual / 25

[phone] or through JDR Microdevices at [phone]. The only time the SmartWatch is read
is upon power-up, RESTART, or RESET.

DAYTIME is used in many modes and should be set when the PK-12 is first powered up.
Installation is easy: Carefully remove U3, install the SmartWatch chip into U3’s socket, then insert U3

into the top of the SmartW at ch chip. Enter the time and date in DA YTIME and you’re all set. (If you have
the 128K RAM option, use the DS1216D clock chip.)

DCdconn ON|

OFF

Default: OFF

DCDCONN defines how the DCD (Data Carrier Detect) signal affects pin 8 in the RS-232 interface to
your computer or terminal. Some programs, such as PBBS software, require that DCDCONN be ON.

DCDCONN also works in the RAWHDLC and KISS modes. In RAWHDLC and KISS, no packet con­nections are known to the PK-12. With DCDCONN ON, the state of the radio DCD is sent to the RS-232
DCD pin (pin-8). This may be necessary to some Host applications that need to know when the radio
channel is busy.

DELete ON|

OFF

Default: OFF

The PK-12 offers you two choices for editing text you hav e typed. You may delete characters using either
the backspace ($08) key, or the delete ($7F) key. Use this command to select the key of y our choice.
Turning DELETE ON enables editing with the delete key, OFF allows you to delete with the backspace
key .

Refer to BKONDEL to see how the PK-12 indicates deletion.

DFrom ALL, NONE,YES/NO call1,call2... Default: ALL

DFROM determines how your PK-12 responds to stations trying to use your station as a digipeater. Type
DFROM to display the ALL, NONE, YES list/NO list status of station’s call signs whose packets will or
won’t be digipeated.

To allow one or more specific stations to digipeat through your station, type DFROM YES, followed by a
list of call signs. To prevent one or more specific stations from digipeating through your station, type
DFROM NO (followed by a list of call signs). To prevent all stations from digipeating through your sta­tion, type DFROM NONE.

Clear DFROM with %, &, or OFF as arguments.

DIGipeat ON|

OFF

Default: ON

ON - The PK-12 will digipeat packets from all other stations if DFROM is set to ALL.
OFF - The PK-12 will not digipeat packets from other stations if DFROM is set to ALL or NONE.

DIGIPEAT is included only to maintain upward compatibility with the TAPR TNCs and some BBS soft­ware that depend on this command being there. The command DFROM is m uch more versatile, and
should be used instead of DIGIPEAT.

Make sure that DFROM is set to ALL if your software needs DIGIPEAT.

26 / PK-12 Packet Controller Operating Manual

Disconne

The DISCONNE command instructs the PK-12 to disconnect from the station you are currently con­nected to. If your disconnect command is successful, your monitor will display:

*** DISCONNECTED: (call)

Other commands may be entered while a disconnect is in progress, although new connections aren’t al­lowed until the disconnect is completed.

If another disconnect command is entered while your PK-12 is trying to disconnect, your PK-12 will in­stantly switch to the disconnected state.

DISPlay

class

One of the most important commands is DISP—it generates a list of commands and their current settings.
To see a brief list, enter DISP. Your screen should now display:

(See also DISPLAY A,B,C,F,I,L,M,R,T,Z)
ConnectLink state is: DISCONNECTED
Opmode PAcket
EXPert OFF
FRack 5 (5 sec.)
HBaud 1200
MAXframe 4
Monitor4 (UA DM C D I UI)
MYcall PK12
MYSelcal none
PACLen 128
TXdelay 30 (300 mS)
cmd:

By typing an argument after DISP, like DISP A, you can call up a sub-list with a different set of com­mands. If you want to list all of the available commands and their settings, enter DISP Z.

The arguments for class are: (A)sync displays serial (asynchronous) port parameters

(B)BS displays packet and MailDrop parameters
(C)haracter displays special characters
(I)d displays ID parameters
(L)ink displays link parameters
(M)onitor displays monitor parameters
(T)iming displays timing parameters
(Z) displays the entire parameter list

DW ait

n

Unless the PK-12 is waiting to transmit digipeated packets, DWAIT forces your PK-12 to pause DWAIT
x 10 mS after last hearing data on the channel before keying your transmitter. You may set DWAIT from
0 to 2.5 seconds in 10 millisecond increments (0-250).

DWAIT is an old way digipeated packet collisions were avoided. Now days, the P-Persistent method is
generally used. With PPERSIST ON (default), the DWAIT timer is ignored.

Default: 16 (160 mS)

PK-12 Packet Controller Operating Manual / 27

Echo ON|

OFF

Default: ON

Depending on the terminal program you use with the PK-12, you may not see what you type, or you may
see double characters. If you don’t see the letters that you type, but the PK-12 responds to the com­mands, you need to enable the ‘echo’ function. This will return (or echo) each c haracter that you type to
your screen. The ECHO command only works in the command and converse modes (not tr ansparent). If
you see each character twice, your terminal is already echoing the characters. You need to turn ECHO
OFF. ECHO is set pr operly when you see the char acters you type displa yed correctly.

EScape ON|

OFF

Default: OFF

ESCAPE selects the character to be output when an (ESCAPE) character is sent to the terminal. The (ES­CAPE) character selection is provided because some computers interpret the ESCAPE character as a spe­cial command. Set ESCAPE ON if you have an ESCAPE-sensitive computer to avoid unexpected results
from accidentally receiving this character. This will force the PK-12 to display all (ESCAPE) characters
as ‘$’.

EXPert ON|

OFF

Default: OFF

Some new PK-12 owners find the large number of available commands daunting. The EXPERT com­mand limits the user’s access to the simplest, most often used commands. Generally, about half of the
commands are available to you after a RESET (EXPERT OFF).

With EXPERT OFF, expert-level commands may not be accessed and don’t appear in any output of the
DISPLAY command—an attempt to use one of these commands will result in the error message “?EX-
PERT command.”

All immediate commands (e.g., CONNECT, PACKET, etc.) are “Novice” commands.

Flow ON|

OFF

Default: ON

With FLOW ON (default), any character typed on your keyboard halts the output from your PK-12 to the
computer until any of the following occurs:

• A packet is sent (in Converse mode).

• A line is completed (in Command mode).

• The packet length ****(PACLEN)**** is exceeded.

• The current packet or command line is cancelled.

• The REDISPLAY character is typed.

• The packet channel is changed.
Setting FLOW ON prevents received data from interfering with your keyboard data entry. With FLOW

OFF, data is sent to the terminal whenever it’s available.

FRack

n

Default: 5 (5 sec.)

FRACK is the FRame ACKnowledgment time in seconds that your PK-12 will wait for acknowledgment
of a sent protocol frame before “retrying” that frame.

After sending a packet requiring acknowledgment, the PK-12 waits for FRACK seconds before increas­ing the retry counter and sending another frame. If the packet address includes any digipeaters, the time
between retries is adjusted to:

Retry interval (in seconds) = n x (2 x m+1), where “m” is the number of intermediate
relay stations.

28 / PK-12 Packet Controller Operating Manual

When a packet is retried, a random wait time is added to any other wait times. This avoids lockups where
packet stations repeatedly collide with each other due to timing conflicts.

FRACK may be set from 1 to 15 seconds in 1 second increments.

FREe

Typing FREE displays the number of usable bytes left in the MailDrop, as in FREE 3724.

FRIck

n/n

FRICK is a short version of FRACK, meant to be used in packet radio meteor scatter work. If FRICK is
0 (default), the FRACK timer is then used and the PK-12 opera tes as before with the retry timer in units
of whole seconds. If FRICK is 1 to 250, it overrides FRACK as the unit’s retry timer, and the retry timer
is in units of 10 mS up to 2500 mS (2.5 seconds).

Unlike FRACK, FRICK doesn’t take into account the number of digipeaters in the connect path. FRICK
assumes that no digipeaters are being used.

Do not attempt multiple packet connections while FRICK is active (1-250). In contrast to FRACK, which
provides one retry timer per multi-connect channel, there is only one FRICK timer in the PK-12. Each
channel will try to use the same FRICK timer, causing interference to the operation of the other channels.

Default: 0/0 (0 sec.)

NOTE:

Due to the sporadic nature of meteor scatter work, a Master/Slave mode can be enabled with User BIT 18
(UBIT 18). With UBIT 18 OFF, FRACK operates the same as before.

With UBIT 18 ON, a master/slave rela tionship is established in packet radio connections. This is done to
reduce the possibility of simultaneous transmissions by both sides of a packet connection. In this mode,
the master station sends either an I-frame or a polling frame upon the expiration of FRICK (or FRACK if
FRICK = 0). The FRICK or FRACK timer then starts counting again. The master station therefore sends
packets constantly, even if all its I-frames have been acknowledged. The slave sta tion sends nothing, not
even I-frames, until it receives a polling frame from the master. A station becomes the master upon its
transmission of a SABM (connect) frame; a station becomes the slave upon its transmission of a UA (ac­knowledgment of the SABM) frame.

Recommended settings for this method (both stations should use these):

UBIT 18 ON
RETRY 0
AX25L2V2 ON (default)
MAXFRAME 1
CHECK (doesn’t matter)
FRICK n, where n is large enough to allow the other station time to send the start of an acknowl-

edgment frame.

FUlldup ON|

OFF

Default: OFF

When full duplex mode is OFF (default), the PK-12 makes use of the DCD (Data Carrier Detect) signal
from its modem to avoid collisions. When ON, the PK-12 ignores the DCD signal and acknowledges
packets individually.

Full-duplex is useful for full-duplex radio operation, such as through OSCAR satellites. It shouldn’t be
used unless both stations can operate in full-duplex.

PK-12 Packet Controller Operating Manual / 29

GENDchar “n” Default: $0D (CTRL-M)

The default GENDchar of $0D requires the string to end with a CR,LF to conform with the NMEA for­mat. If this is changed, the sentence will end with whatever character is programmed. T his command
does not need to be programmed for use with GPS or Loran devices. It is intended for use with other for­mats.

GINIText text Default: None

text- Any combination of characters up to a maximum length of 60 characters.
This text will be sent to the serial port when the PK-12 is powered up with GPSMode NO T equal to zero.

This text is intended for an initialization string for OEM GPS cards requiring setup after power-down. If
not programmed, the PK-12 will send nothing at power-up.

GLOCtx “n” Default: 0 (00 sec.)

“n” - 0 to 255 sets the location timing in ten-second increments.
“0” - Zero disables automatic location transmissions.
GLOCtx is used to periodically transmit GPS data received on the serial port. GLOCtx is programmable

from 0 (never) to 2500 seconds in 10 second intervals. A transmission will only occur if, GPSMode = 1
or 2, GLOCtx is not zero, and the correct NMEA information is received on the serial port.

GNMEA1 Text (0-8 chars) Default: GPGLL (GPS position only)

This is the string the PK-12 will parse from the NMEA device. The text can be any ASCII character.

GNMEA2 Text (0-8 chars) Default: None

This is another string the PK-12 will parse from the NMEA device. The text can be any ASCII character.

GPOLLCal call[-”n”] Default: None

call - The callsign you wish to use for polling.
“n” - Numeral indicating an optional SSID.
The POLLCal can be any callsign other than one already programmed in the PK-12. If programmed the

same as the MYAlias, MYCall, MYGate, or MYMail callsigns, this polling feature will not work. When
a packet is received addressed to the GPOLLCall callsign, the PK-12 will begin parsing the programmed
NMEA command or commands. When the NMEA headers are successfully received, the PK-12 will
transmit the GPS data as a UI-Frame. This GPOLLCall can also be used for digipeating.

GPSAuto ON|OFF Default: OFF

ON - When powered up or restarted, the PK-12 switches to GPSMode 1 if it parses its GNMEA1 or
2 sentence within the first 4 seconds after power up.

OFF - The PK-12 powers up normally.
If you are using your PK-12 in your vehicle as a stand alone tracking device and in your home for regu-

lar packet operation, this command will save you a lot of hassles. Simply program all your GPS param­eters except for the GPSMode command, turn GPSAuto ON and you’re set. Each time you turn your
TNC on, the PK-12 will spend the first four seconds after power up trying to parse its GNMEA sentence
or sentences. If it successfully parses one or both of them, it will automatically switch to GPSMode 1.

30 / PK-12 Packet Controller Operating Manual

To have the PK-12 auto detect a GPS receiver, follow these steps:

1. Be sure you have your GPS command programmed.

2. Be sure GPSAuto is turned ON.

3. Connect the GPS receiver to the PK-12 serial connector.

4. Apply power to the GPS r eceiver (NOT THE PK-12 YET).

5. Be sure that the GPS receiver is outputting its NMEA data before powering up the PK-12.

6. Power up the PK-12 and within 4 seconds, you should notice the PK-12 transmit LED
lighting to transmit its location.

GPSMode “n” Default: 0 Disabled

This is a variable ranging from 0-3 that selects a specific mode of operation specific to GPS. Three
CTRL-C’s returns unit to GPSMode 0.

Mode 0 = Normal Packet TNC operation. (GPS operation disabled.)
Mode 1 = PK-12 connected directly to a GPS receiver.

The PK-12 will begin parsing its programmed NMEA sentences under the following
conditions:

1. GLOCtx timer expires

2. The PK-12 receives an Unproto frame containing ?APRS?

3. The PK-12 receives an Unproto frame containing MYCALL..:?APRS?

4. The PK-12 receives an Unpr oto frame addr essed to its POLLCALL

Upon reception of one of these types of frames, the PK-12 will begin to parse its programmed NMEA
sentences. If the PK-12 successfully parses one or both of its NMEA sentences, it will transmit the infor­mation parsed as a single UI frame. If there is no data received from the GPS receiver within four sec­onds, it will reset its GLOCtx timer and continue.

Mode 2 = PK-12 connected directly to an ULTIMETER II.
The PK-12 will begin parsing its programmed NMEA sentences under the following

conditions:

1. GLOCtx timer expires

2. The PK-12 receives an Unproto frame containing ?WX?

3. The PK-12 receives an Unproto frame containing MYCALL..:?APRS?

4. The PK-12 receives an Unpr oto frame addr essed to its POLLCALL

Upon reception of one of these types of frames, the PK-12 will begin to parse its programmed NMEA
sentences. If the PK-12 successfully parses one or both of its NMEA sentences, it will transmit the infor­mation parsed as a single UI frame. If there is no data received from the GPS receiver within four sec­onds, it will reset its GLOCtx timer and continue.

Variable Number 3 For Commercial Use Only

Mode 3 = PK-12 connected to a GPS receiver & computer terminal (using Timewave Commercial GPS
adapter cable).

PK-12 Packet Controller Operating Manual / 31

When the LOCtx timer expires or if the PK-12 receives a UI frame addressed to its GPOLLCall, the PK­12 will switch the serial port to receive data from the GPS receiver. After the NMEA commands are
parsed, the PK-12 will transmit the information obtained as a UI-frame and switch the serial port back to
the computer. If there is no data received from the GPS receiver within four seconds, the PK-12 will
switch back to the computer and transmit nothing.

GREMprog ON|OFF Default: OFF

ON - Remote programming is enabled in GPS mode.
OFF - Remote programming is disabled in GPS mode.

While operating in one of the GPS modes, the following commands can be programmed:

1. GLOCtx

2. GNMEA1

3. GNMEA2

4. GINIText

5. GSYMchar

6. Unproto

To remotely pr ogram the PK-12, the programming sta tion must have its Unproto destination callsign set
to match the GPOLLcall of the PK-12.

Example:

Let’s say you have a PK-12 in your car as a stand alone tracker with its GPOLLcall set to CAR. In
your house, you would program your TNC’s Unproto to CAR (U CAR). Now place your TNC in
converse mode by typing either (K or CONVerse). If you wanted to change the PK-12 in the
car’s Unproto path, you would simply type U APRS via RELAY <CR>. Your TNC in your home
would transmit the following frame:

Home TNC:

{your callsign}*>CAR [UI]:
U APRS via RELAY

PK-12 in car would reply:

PK12*>RELAY>APRS [UI]:
++ done

Note that the PK-12 in the vehicle replied with the message ++ done. This indicates that the command
was properly received and the parameter was changed. The following is a list of additional messages and
their meaning.

Remote programming messages:
Message Meaning

++ done the parameter was programmed
++ bad not supported, incorrect format, or bad data
++ too many too many parameters entered
++ range numeric entry is too large

32 / PK-12 Packet Controller Operating Manual

GSYMChar “n” Default: 0 None

This is a Hex value ranging from 0-255 that represents a symbol in APRS software. The symbol char will
be enclosed in curly brackets before all Beacon transmissions.

KA7SYZ*>RELAY>APRS [UI]:
{SYMChar} This is a sample UI frame...

GUNSTart ON|OFFDefault: OFF

ON - The PK-12 starts in CONVERSE mode after a restart or power-up.
OFF - The PK-12 will power-up in command mode.
This command allows the PK-12 to power-up in the converse mode if turned on.

GUSERS

n

Default: 0

GUSERS allows up to n number of stations to connect to your MYGATE call. The argument “n” may be
0-3, with zero meaning no station can use your node. Alternatively, n can be thought of as the maximum
number of pairs of stations which may be connected through your Gateway.

You must have your MYGATE call entered and GUSERS set to a number greater than 0 to enable the
PK-12’s node function.

HEAderln ON|

OFF

Default: ON

HEADERLN is used to control the output of packet text. With HEADERLN ON, the address is shown
followed by a (RETURN)+LF that puts the packet text on a separate line as shown below:

KG6ZL>WF7A:
Go ahead and send the file, Rich.

With HEADERLN OFF, the address information is shown on the same line as the packet text as shown
below:

KG6ZL>WF7A:Go ahead and send the file, Rich.

HID ON|

OFF

Default: OFF

Set HID ON to force your PK-12 to send an ID packet every 9.5 minutes when it’s used as a digipeater.
Otherwise, leave HID OFF (default). The ID consists of a UI-frame with your station identification
(MYCALL) and MYALIAS in the data field. It is addressed to “ID.”

Please note that you can’t change the 9.5-minute automatic interval timing.

HOMebbs

call

This command sets the call sign of your local or HOMEBBS that you’ll use for reverse-forwarding mes­sages. You must make special arrangements with the system operator of this BBS to set you up for re­verse-forwarding. The SSID isn’t compared when matching HOMEBBS to the source call sign of an in­coming packet.

Host

n

“n” A hexadecimal v alue from $00 through $FF setting bits from the table below that def ine the Host

operation of the PK-12.

Default: (none)

Default: 0

PK-12 Packet Controller Operating Manual / 33

The Host command enables the “computer-friendly” Host communications mode over the PK-12’s RS­232 link. To exit out of the Host mode, enter three (CTRL-C) characters in rapid succession or type
(CTRL-A),O,H,O,N,(CTRL-W). Sending a Break signal won’t cause the PK-12 to exit from the Host

mode.

Bit 0: Controls whether the Host mode is ON (1) or OFF (0).
Bit 1: Controls the local MailDrop access.

If bit 1 is 0, then the MailDrop Send data uses the $20 block. Read data uses the $2F block as
before. Monitored MXMIT data uses the $3F (monitored receive) block type.

If bit 1 is 1, then the MailDrop send data uses the $60 block type. Read data uses the $70 block
type. Monitored MXMIT data uses the $2F (echoed) block type to differentiate between moni-

tored, transmitted, and received frames.
Bits 2-7 are reserved for future use.
To maintain backward compatibility with older programs written to use the ON|OFF form of the Host

command, Host ON is equivalent to Host $01 described above. However, programmers must note that
Host now returns a numeric value and not ON or OFF as before.

See Time w ave’s PK-232MBX Technical Manual for full information a bout the Host mode.

HPoll ON|

OFF

Default: ON

HPOLL is used in conjunction with the host mode and sets the method used by the host mode software
for retrieving data from the PK-12.

With HPOLL ON, the Host mode program must poll the PK-12, using (CTRL-A),O,G,G, (CTRL-W),
for all data that might be available to be displayed. With HPOLL OFF, the Host mode program must ac­cept any data from the PK-12 when it becomes available.

ID

ID is an immediate command that sends a special identification packet. The ID command sends a final
identification packet when you take your station off the air. (HID must also be set ON). The identification
consists of a UI-frame, with its data field containing your MYALIAS (if it’s entered), MYCALL, and the
word “digipeater.” The ID packet is sent only if your PK-12 has digipeated any transmissions since the
last automatic identification.

ILfpack ON|

OFF

Default: ON

The ILFPACK command permits you to control the way the PK-12 sends LF characters received from
your computer while in the packet mode. Enabling ILFPACK causes the PK-12 to ignore all line feed
(LF) characters sent by your terminal, while disabling it allows all LF characters to pass through.

IO

n

Default: none

The IO command works with the ADDRESS command (ADDRESS $aabb) and permits access to
memory and I/O locations. Use the IO command without arguments to read an I/O location, and with one
argument—$0 to $FF—to write to an I/O loca tion. The value in ADDRESS isn’t increased after using
the IO command.

In ADDRESS $aabb, aa (01-FF) is the device address, and bb is the register address.
In ADDRESS $00bb, the IO command reads or writes data to the device at I/O address bb. There is no

register set-up before the access. ADDRESS is used as a programmer’s aid and isn’t needed for normal
use.

34 / PK-12 Packet Controller Operating Manual

KILONFWD ON|

OFF

Default: ON

KILONFWD controls the disposition of a message that has been reverse-forwarded to the station whose
call is input in HOMEBBS. W ith KILONFWD ON, the message is deleted automatically after it has been
forwarded to make room for other messages in your MailDrop. With KILONFWD OFF, the message’s
status is changed from “F” to “Y.”

KIss

n

Default: OFF

The KISS mode must be entered to prepare the PK-12 for KISS operation. TCP/IP and other special ap­plications have been written that require the KISS mode be on. For normal AX.25 packet operation, this
command should be left at OFF (default).

KISS OFF: KISS disabled
KISS ON: Standard KISS
In KISS and Raw HDLC modes, communication activity on the RS-232 link is shown by lighting the

STA and CON LED’s as follows:
Host to TNC Communication: STA LED illuminated.

TNC to Host Communication: CON LED illuminated.
Host OFF—entering three (CTRL-Cs)—will force KISS OFF. Details on the use of KISS TNC protocol

are in Timewave’s Technical Reference Manual — Model PK-232 Data Controller.

LAstmsg

n

The number, 0-999, is the number assigned to the last message sent by a remote user (or the SYSOP) to
the MailDrop. This command is handy for checking the last message sent to your MailDrop system.
LASTMSG also allows the MailDrop message counter to be set to any value, or simply reset the counter
to zero by entering LASTMSG 0.

LOWPow Default: OFF

With LOWPow ON, the DCD, CON, STA, and MAIL LEDs will not light, allowing low power opera­tion. The XMT and POWER LEDs will still light with this command enabled. With LOWPow off , all
LEDs will function normally. See Appendix D for more information.

MAildrop ON|

OFF

Default: OFF

The MailDrop is a personal mailbox that uses a subset of the W0RLI/WA7MBL PBBS commands. With
MAIL DROP ON, other stations can connect to your PK-12, leave messages for you or read messages
from you. Third-party messages are not accepted unless 3RDPARTY is ON.

MAXframe

n

Default: 4

MAXFRAME limits the number of nacked packets your PK-12 permits on the radio link and the number
of sequential packets your PK-12 will send.

The optimum value of MAXFRAME depends on your local channel conditions. In most cases, the de­fault value of MAXFRAME 4 works well. When the amount of traf fic is heavy, the path in use is poor, or
if you’re using many digipeaters, you can actually improve your throughput by reducing MAXFRAME.

MAXFRAME is adjustable from 1 to 7.

PK-12 Packet Controller Operating Manual / 35

MBEll ON|

OFF

Default: OFF

MBELL can be used to alert you to activity from particular packet stations. MBELL will send 3 BELL
characters to the terminal when the call sign(s) of the station(s) monitored match the MFROM and MTO
lists. For example, if you want to be alerted when KG6ZL comes on frequency, you’d enter:

cmd:MBELL
cmd:MONITOR 4 (or the value you prefer)
cmd:MFROM
cmd:MTO

ON

YES KG6ZL

NONE

With MBELL ON, packets from—and to all—stations are displayed, but only those packets matching the
MFROM and MTO lists cause BELL to ring .

MBx

call1[,call2

][-n][

ALL

] Default: NONE

call The call sign(s) of one or two stations to be monitored.
“n” 0 to 15, indicating an optional SSID.
MBX lets you read or record useful or needed data without having to connect or log on to the source

station(s). MBX filters the received packet data so that only packets from the selected station(s) entered
above are shown, without headers or repeated frames. MBX overrides normal monitor functions and can
show one or both sides of a conversation.

The operation of MBX command is as follows:
MBX NONE All monitored frames are shown with their headers.
MBX ALL Only the data fields in the I-frames and UI frames are shown. Data from retried frames

will be shown each time such a frame is monitored. The MFROM and MTO com­mands are active.

MBX call1 Only the data in the I and UI frames to or from call1 are shown. call1 can be either the

source or destination station. Retried frames are not shown. The MFROM and MTO
commands are ignored.

MBX call1,call2 Only the data in the I and UI frames are shown when call1 is the source and call2 is the

destination or vice-versa. Retried frames aren’t shown. The MFROM and MTO com­mands are ignored.

A packet connection on any channel inhibits monitoring if MBX isn’t set to NONE. MCON only works
if MBX is set to NONE. Clear MBX with %, &, N, NO, NONE, or OFF as arguments.

MCon

n

Default: 0 (none)

MCON works similarly to MONITOR, but MCON affects your display only while you’re connected to
another station. If MCON is set to a value between 1 and 5, frames meant for you are displayed as

though MONITOR was OFF—you’ll see only the data and not any header information. With MCON 6,
frames meant for you are displayed as any other monitored frame—the headers appear with the data.

Starting with 0, as you increase the value of n the more “stuff” will be visible with each pac ket you re­ceive:

0 You won’t monitor any packets while you’re connected.
1 Only unnumbered (UI) frames resulting from an unconnected transmission are displayed. Use

this for an “unproto,” r oundtable-type conversation where you want to read another station’s

packet text—sent unproto—while you’re connected. This setting also displays beacons.

36 / PK-12 Packet Controller Operating Manual

2 Numbered (I) frames are also displayed. Use this to monitor connected conversations in progress

outside your own.

3 Connect request (SABM or “C”) frames and disconnect (DISC or “D”) frames are also dis-

played with the headers.

4 Unnumbered acknowledgment (UA) of connect- and disconnect-state frames are also displa yed

with either the characters “UA” or “DM” and a header.

5 Receive Ready (RR), Receive Not Ready (RNR), Reject (RJ), Frame Reject (FRMR) and (I)

Frames are also displayed.
6 Poll/Final bit, PID and sequence numbers are also displayed.
See MONITOR about monitoring packets while you’re not connected.

MDCheck

MDCHECK allows you to log on to your own MailDrop. After logging on, you can EDIT, LIST, READ,
SEND, or KILL MailDrop messages.

To use MDCHECK, your PK-12 must not be connected to or linked to any packet stations. For monitor­ing purposes, local access of the MailDrop is considered a connection. Enter “B” (B)ye to exit the
MailDrop.

MDigi ON|

OFF

Default: OFF

MDIGI lets you display packets when another station uses your station as a digipeater. If you want to
monitor all traffic that flows through your station, set MDIGI ON. Note that your callsign is set using the
MYCALL and MYALIAS commands.

You may not want to see all the data passing through your station, especially if many others use you as a
digipeater. In this case set MDIGI OFF.

MDMon ON|

OFF

Default: OFF

MDMON permits you to monitor activity on your MailDrop, showing you both sides of the QSO (P ack et
headers aren’t shown while a caller is connected). When no one is connected to your MailDrop, channel
activity is monitored according to the setting in MONITOR.

Note that MailDrop connect and link status messages will be displayed even with MDMON OFF. These
status messages are important and allow you to see who is connected to your MailDrop. They can be dis­abled with UBIT 13 (See UBIT for more information).

MDPrompt

text

Default: (see text)

MDPROMPT is the command line (up to 80 characters) sent to a calling station by your packet MailDrop
in response to a Send message command. The default text is:

Subject:/Enter message, ^Z (CTRL-Z) or /EX to end

Text before the first slash is sent to the other station as the Subject prompt; text after the slash is sent as
the message text prompt.

If there’s no slash in the text, the subject prompt is “Subject:” and the text prompt message is Enter

message, ^Z (CTRL-Z) or /EX to end.

PK-12 Packet Controller Operating Manual / 37

MEmory

n

Default: NONE

MEMORY works with ADDRESS (ADDRESS $aabb) and permits access to memory locations. Use the
MEMORY command without arguments to read a memory, and with one argument ($0 to $FF) to write
to a memory location. The value in ADDRESS is increased after using the MEMORY command. This
command is used solely for test purposes.

MFilter n1[,n2,n3,n4] Default: $80

Use MFILTER to select up to 4 characters to be “filtered” or excluded from monitored packets with pa­rameters n1 - n4, the ASCII codes (0-128) for the characters you want to filter. The special value of $80
(default) filters all characters above $7F and all control-characters except (RETURN) ($0D), LF ($0A),
and (TAB) ($09).

MFrom ALL|NONE or YES|NO call1[,call2...] Default: ALL

MFROM determines what packets are or aren’t to be monitored. To monitor all packets set MFROM to
ALL. To stop all packets from being displayed, set MFROM and MTO to NONE.

To display packets from one or more specific stations, type MFROM YES followed by a list of call signs
you want to monitor packets from. To block packets from one or more specific stations, type MFROM
NO followed by a list of call signs you don’t want to hear packets from. When using MFROM, set MTO
to NONE.

You can include optional SSIDs specified as “-n” after the call sign. For example, with MFRO M NO
WF7A, packets from WF7A-0 through WF7A-15 won’t be monitored. With MFROM YES WF7A-1, then
only WF7A-1 will be monitored. When MFROM and MTO contain different arguments, the following
priority applies:

1. ALL

2. NO_list

3. YES_list

4. NONE
Clear MFROM with %, & or OFF as arguments.

MHeard

MHEARD displays a list of the 18 most recently heard stations.
When DAYTIME has been set, entries in the Heard log are time stamped. With DAYSTAMP ON the

date is also shown. This is an example of the MHEARD display:
DAYSTAMP ON DAYSTAMP OFF

05-Nov-93 21:42:27 KG6ZL 21:42:27 KG6ZL
05-Nov-93 21:42:24 KB6IUX* 21:42:24 KB6IUX*
Previously, stations heard directly were displayed with an asterisk (W1AW*) and digipeated stations were

shown without (W2SZ). Digipeating isn’t used as much as it used to be—most stations now use nodes, so
we’ve stopped using the asterisk. However, for those few cases in which a station is heard indirectly
through a digipeater, that station’s call sign is displayed with the message, “via digi”.

In addition, I- and U-frame packets with PIDs of CF and CD are shown with the indicators “N/R” (for
Net/ROM) and “IP” respectively.

Clear the MHEARD list with %, &, N, NO, NONE, or OFF.

38 / PK-12 Packet Controller Operating Manual

MId

n

MID is used to periodically assure 20 WPM Morse ID. MID is programmable from 0 (off) to 2500 sec­onds in 10 second increments. An ID will be transmitted only if a packet was sent since the last ID. The
ID uses TXDELAY, PPERSIST, and DCD.

If MID is set to a value other than 0, ID will force a Morse ID immediately. If both HID and MID are ac­tive, the Morse ID will be sent first.

MID normally sends a Morse ID using on/off keying of the low tone. If FSK keying of both tones is de­sired to prevent stations from transmitting over your Morse ID, see the UBIT 12 command.

Default: 0 (00 sec.)

MMsg ON|

OFF

Default: OFF

MMSG enables or disables automatic transmission of the MTEXT message when your MailDrop links
with another station.

Monitor

n

Default: 4 (UA DM C D I UI)

The MONITOR command is used to select the amount of traffic to be displa yed while the PK-12 is
monitoring the channel. Starting with 0, as you increase the value of MONITOR, the more “stuff” will be
visible with each packet you intercept:

0 You won’t monitor any packets while you’re unconnected.
1 Only unnumbered (UI) frames resulting from an unconnected transmission are displayed. Use this

for an “unproto,” roundtable type conversation where you want to read other station’s packet text—
sent unproto—while you’re not connected. This setting also displays beacons.

2 Numbered (I) frames are also displayed. Use this to monitor connected conversations in progress.
3 Connect request (SABM or “C”) frames and disconnect (DISC or “D”) frames are also displayed

with the headers.

4 Unnumbered acknowledgment (UA) of connect- and disconnect-state frames are also displayed with

either the characters “UA” or “DM” and a header.

5 Receive Ready (RR), Receive Not Ready (RNR), Reject (RJ), Frame Reject (FRMR), and (I)

Frames are also displayed.
6 Poll/Final bit, PID and sequence numbers are also displayed.
If you want to save your PK-12’s buffer from filling up with unwanted packets, set MONITOR to zero.

That way , you’ll still be able to store mail sent to you and receiv e connect requests, but the PK-12’s buffer
won’t fill up with “junk mail.”

See MCON about monitoring packets while you are connected.

MProto ON|

OFF

MPROTO is used to select which packet frames are monitored. This is in response to NET/ROM, which
sends frames that have a PID of $CF and that contain control characters. If you want to monitor every
frame including those used by NET/ROM, you must turn MPROTO ON.

Default: OFF

PK-12 Packet Controller Operating Manual / 39

MRpt ON|

OFF

Default: ON

MRPT affects the way monitored packets are displayed. With MRPT ON, the call signs of all stations in

the digipeat path are displayed. The call sign of the station heard directly is flagged with an asterisk (*) as

shown:

KB6IUX-4*>KG6ZL>W1AW-5>W1AW-4:

With MRPT OFF, only the originating station and the destination stations are displayed in the monitored

packet header as shown below:

KB6IUX-4*>W1AW-4:

MStamp ON|

OFF

Default: OFF

MSTAMP activates time stamping of monitored packets. When your PK-12’s internal software clock is

set, date and time information is available for automatic logging of packet activity and other applications.

Remember to set the date and time with the DAYTIME command, first!

With MSTAMP OFF, the packet header display looks like this:

KB6IUX-4*>KA2EYW -1>AI2Q:

With MSTAMP ON and DAYSTAMP OFF, the display looks like this:

22:51:33 KB6IUX-4*>KA2EYW-1>AI2Q:

MTExt

text

Default: See sample

MTEXT is the MailDrop’s “answering machine message,” similar to CTEXT. MTEXT may contain up

to 120 printable characters. With MMSG ON, the MTEXT message is sent when a station links to your

MailDrop. The default text is:

Welcome to my AEA PK-12 MailDrop.
Type H for help.

MTEXT can be reset with a %, &, N, NO, NONE or OFF as arguments.

MTo ALL|NONE or YES|NO call1[,call2...] Default: none

MTO determines which packets are to be monitored. To monitor all packets, set MTO to ALL; for no

packets, set MTO and MFROM to NONE.

To display packets from other stations addressed to one or more specific stations, type MTO YES fol-

lowed by a list of the call sign(s) you want to monitor for their packets. If you don’t want to see the pack-

ets addressed to that (or those) station(s), type MTO NO followed by their call sign(s). When using MT O,

set MFROM to NONE.

You can include optional SSIDs specified as “-n” after the call sign. If MTO is set to NO WF7A, any

variation of WF7A-0,...WF7A-15 won’t be monitored. If MTO is set to YES WF7A-1, then only WF7A-1

will be monitored.

When MFROM and MTO contain different arguments, the following priority applies:

1. ALL 2. NO_list 3. YES_list 4. NONE

Clear MTO with %, &, or OFF as arguments.

40 / PK-12 Packet Controller Operating Manual

MXmit ON|

OFF

Default: OFF

With MXMIT ON, outgoing packets are monitored in the same manner as received packets. The monitor­ing of outgoing packets is subject to the settings of MONITOR, MCON, MFROM, MTO, MRPT and
TRACE. Most transmitted packets occur when you’re connected to someone, so MCON should probably
be set to a non-zero value.

MYAlias

call [-n

] Default: none

MYALIAS specifies an alternate call sign (in addition to the call sign specified in MYCALL) for those
households with two operators taking turns using the PK-12—your TNC will accept connections to both
your MYCALL and MYALIAS. Previously, MYALIAS had been reserved only for stations digipeating
through your station. If MYMAIL isn’t set, the MailDrop also accepts connections to either MYCALL or
MYALIAS. You may also add the substation ID (SSID) in the -n field.

Outgoing connect attempts and Unproto frames use only MYCALL as the source call sign.

MYcall

call [-n

] Default: PK12

Use MYCALL to load your call sign into your PK-12—a default call sign is present in the ROM when
the system is manufactured. This artificial call must be changed for operation.

The SSID is usually added so the PK-12 can respond to two different tasks—as a “base” station and digi­peater, a digipeater and MailDrop, or a base station and MailDrop. An example of using the SSID suffix
is given in Chapter 5: Packet Operation.

Two or more stations can’t use the same call and SSID on the air at the same time. Use a different SSID
if this is the case.

MYGate

call [-n

] Default: none

call Node call sign used by other stations.
“n” 0 to 15, an optional substation ID (SSID).
“Call” is the call sign of the node function of your PK-12. Stations can connect to your MYGATE call

and then issue a connect request from there. This way, your station takes responsibility for acknowledg­ments of the user’s packets.

MYMail

call [-n

] Default: none

MYMAIL is used to set the callsign that other TNC operators use to sign on to your MailDrop.“Call”
may have an optional SSID, and must not be the same call sign and SSID as MYCALL. If you don’t set
MYMAIL, the MailDrop will use the same call sign and SSID as you entered in MYCALL. For ex­ample, with MYCALL WF7A, then MYMAIL may be WF7A-1 through WF7A-15. You can use the
CTEXT and MTEXT messages to inform other stations about your MYCALL and MYMAIL call signs
when they connect to you.

NEwmode ON|

OFF

Default: ON

Your PK-12 always switches to a data transfer mode—Transparent, Converse, or Command—at the time
of connection unless NOMODE is ON. NEWMODE determines how your PK-12 behaves when the link
is broken.

With NEWMODE ON, when the link is disconnected (or if the connect attempt fails), the PK-12 returns
to the Command mode. With NEWMODE OFF, when the link is disconnected, the PK-12 remains in
Converse or Transparent mode unless you “manually” for ce it to return to the Command mode.

PK-12 Packet Controller Operating Manual / 41

NOmode ON|

OFF

Default: OFF

With NOMODE OFF, your PK-12 switches modes automatically according to NEWMODE. With

NOMODE ON, your PK-12 never switches from Converse or Transparent mode to Command mode (or

vice versa) by itself. Only specific commands—CONVERSE, TRANS, or (CTRL-C )—entered by you

will change the operating mode.

NUCr ON|

OFF

Default: OFF

Some older printer-terminals require extra time for the printing head to do a (RETURN) and LF. NUCR

ON solves this problem by making your PK-12 send null characters (ASCII code $00) to your computer.

NULLs

n

Default: 0 (zero)

NULLS specifies the number of null characters (ASCII $00) to be sent to the computer after a (RE-

TURN) or LF is sent. NUCR and/or NULF must be set to indicate whether nulls are to be sent after (RE-

TURN), LF, or both. The null characters are sent only in the Converse and Command modes. You may

instruct the PK-12 to send any number of nulls from 0 (none) to 30.

PACLen

n

Default: 128

PACLEN sets the maximum number of characters to be sent in each packet burst. Most keyboard-to-key-

board operators use the default value of 128 bytes for routine VHF/UHF packet services. Your PK-12 au-

tomatically sends a packet when you reach “n” bytes. For example, if you set PACLEN to 256, the PK-12

will send out a packet burst after you enter 256 bytes’ worth of information.

PACTime

EVERY|AFTER n

Default: AFTER 10 (1000 mS)

The PACTIME parameter sets the amount of time, in 100 mS increments, that the PK-12 will wait for a

character to be entered before sending a packet in the Transparent mode. The PACTIME parameter is

also used in Converse mode if CPACTIME is ON.

When EVERY is specified, the characters you type are “packetized” every n x 100 mS. When AFTER is

specified, the characters you type are “packetized” when input from the terminal stops after waiting n x

100 mS.

The PACTIME timer is not started until the first character or byte is entered. A value of 0 (zero) for “n”

means packets are sent with no wait time.

PARity

n

Default: 3 (even)

PARITY sets the PK-12’s parity for RS-232 terminal according to the table below:

0 = no parity

1 = odd parity

2 = no parity

3 = even parity

The parity bit, if present, is stripped automatically on input and isn’t checked in Command and Converse

modes. But in Transparent mode, all eight bits (including parity) are transmitted.

The change won’t take effect until you enter RESTART. Be sure to change the computer or terminal to

the same parity setting after you’ve entered RESTART.

42 / PK-12 Packet Controller Operating Manual

PASs

n

PASS selects the ASCII character (0 to 127) “n” used for the “pass” input editing commands. The PASS
character signals that the following character is to be included in a packet text string. For example, if
you’re typing in text and want to enter three (RETURN)’s so you can put a line space between two para­graphs, you’d do this:

“...here’s the end of the first paragraph.” (CTRL-V)+(RETURN)+(CTRL-V) (RETURN).“Now this
line will appear after a line space.”

The line will appear at the other station like this:

“...here’s the end of the first paragraph.”
“Now this line will appear after a line space.”

If you had just pressed (RETURN) at the end of the word “paragraph,” you would have forced a packet
to be sent. Press (RETURN) again, and you would have forced an empty packet to be sent. Press (RE­TURN) yet again, and another empty packet would have been sent. This happens because pressing (RE­TURN) normally forces a packet to be sent. However, by inserting a (CTRL-V) before a (RETURN),
you disable the function of (RETURN) in the Command mode and allow it to be used in your outgoing
text to act as a “real” (RETURN). So, the PASS character “hides” the next character’s function.

Default: $16 (CTRL-V)

PASSAll ON|

OFF

Default: OFF

PASSALL turns off the packet error-detecting control and displays received pac kets with invalid CRCs.
PASSALL is normally turned OFF, to ensure that data is error-free by rejecting packets with invalid CRC
fields. W ith PASSALL ON, packets are displayed despite CRC errors.

MHEARD logging is disabled since the call signs detected may be incorrect.

PErsist

n

Default: 63

PERSIST works with PPERSIST and SLOTTIME to achieve true P-persistent CSMA (Carrier-Sense
Multiple Access) in packet operation. PERSIST’s paramater may be set from 0 to 255.

PK [n] Default: none

PK (Peek/Poke) permits access to memory locations. To use the PK command:

• Set the memory address into the ADDRESS command.

• Use the PK command without arguments to read that memory location.

• Use PK with one argument 0-$FF to write to that memory location.
RAM locations are $8000-$FFFF. ROM begins at $0000. This command is primarily a programmer’s aid

and is not needed for normal PK-12 use.

PPersist ON|

OFF

Default: ON

With PPERSIST ON, the PK-12 uses the PERSIST and SLOTTIME parameters for P-persistent CSMA
instead of the older DWAIT CSMA procedure.

When your computer has queued data for transmission, the PK-12 monitors the DCD signal from its mo­dem. When the channel clears, the PK-12 generates a random number between 0 and 255. If this number
is less-than or equal to PERSIST , the PK-12 transmits all the frames in its queue. If the random number is
greater than “P”, the PK-12 waits .01 x SLOTTIME (seconds) and repeats the attempt.

PPERSIST can be used in both KISS and normal operation.

PK-12 Packet Controller Operating Manual / 43

RAWhdlc ON|

OFF

Default: OFF

The RAWHDLC command enables the PK-12 to bypass the AX.25 packet implementation. Host mode

must be on to communicate with the PK-12 in the RAWHDLC mode.

See s’s Technical Reference Manual—PK-232 Data Controller for full information.

REDispla

n

Default: $12 (CTRL-R)

REDISPLA changes the redisplay-line input editing character.

Parameter “n” is the numeric ASCII code (0-127) for the character you’ll use when you want to re-dis-

play the current input line. Type the REDISPLA character to re-display a command or text line you’ve

just typed. This can be helpful when editing a line, especially if your terminal doesn’t support (BACK-

SPACE). It can also be used in packet to display a packet that might have been received while you were

typing. A backslash (\) is appended to the old line, and the corrected line is shown beneath it.

REINIT

This is an immediate command that you can use to get out of trouble caused by setting a lot of com-

mands—especially timing parameters—to strange values. REINIT can be thought of as being halfway

between RESTART and RESET. REINIT re-initializes most of the commands to their default setting,

then does a RESTART, but the contents of the MailDrop and the NAVTEX message history buffers are

preserved. The commands that are preserved are:

MYCALL MYALIAS MYMAIL HOMEBBS LASTMSG MBX UNPROTO

BTEXT CTEXT PARITY CFROM DFROM MFROM MTO MTEXT

AWLEN HOST TBA UD MDPROMPT

In Host mode, the REINIT command is acknowledged by a RESTART response (RT).

RELink ON|

OFF

Default: OFF

Set RELINK ON if you want the PK-12 to automatically try to reconnect to another packet station if the

link fails.

RESET

RESET resets all of the PK-12’s parameters to their default settings and reinitializes the unit to the point

where you’ll enter the autobaud routine. All personalized parameters, monitor lists, and MailDrop mes-

sages will be lost.

RESptime

n

Default: 0 (000 mS)

RESPTIME adds a minimum delay before your PK-12 sends acknowledgment packets. This delay may

run concurrently with the default wait time set by DWAIT and any random wait in effect. RESPTIME is

programmable from 0 to 25 seconds in 100 millisecond increments.

During a file transfer, RESPTIME can help avoid data and acknowledgment collisions caused by the

sending stations’ TNCs pausing briefly between transmitted data frames.

44 / PK-12 Packet Controller Operating Manual

RESTART

RESTART reinitializes the PK-12 while retaining the settings you’ve changed or entered. The effect of
RESTART is the same as turning the PK-12 off, then on again. RESTART doesn’t reset the values stored
in its battery-backed RAM.

See RESET.

REtry

n

“n” 0 to 15 specifies the maximum number of packet retries before the PK-12 “gives up” sending

that packet.

The AX.25 protocol uses the retransmission of frames that haven’t been acknowledged as a means to en­sure that all transmitted frames are received. The number of retries that the PK-12 will attempt is set from
0 to 15 using this command. If the number of retries is exceeded, the packet link may be lost.

Default: 10

SEndpac

n

Default: $0D ( CTRL-M) or (RETURN)

Use SENDPAC to select the character used to cause a packet to be sent in Converse mode. The parameter
“n” is the ASCII (0-127) code for the character you want to use to force your typed input to be sent. Use
the default SENDPAC value, $0D, for ordinary conversation with ACRPACK ON to send packets at
natural intervals.

SLottime

n

Default: 30 (300 mS)

The SLOTTIME parameter works with the PPERSIST and PERSIST parameters to achieve true p-per­sistent CSMA (Carrier-Sense Multiple Access) in packet operation. SLOTTIME is programmable from 0
to 2.5 seconds in 10 millisecond increments.

SQuelch ON|

OFF

Default: OFF

Normally, your PK-12 uses its CSMA (Carrier Sense Multiple Access) circuit to decide whether or not
it’s clear to transmit on a packet channel. If there are non-packet signals on the channel you’re using—
such as voice—you’ll want to use true RF-carrier CSMA by monitoring the squelch line voltage from
your radio.

With SQUELCH OFF, the PK-12 inhibits transmissions when there is a positive voltage on the radio
connector’s squelch input line. When there is no voltage or connection to this pin, the PK-12 allows pack­ets to be sent.

With SQUELCH ON, the PK-12 will inhibit packet transmissions when no voltage is applied to the
squelch input pin on the Radio connector.

If you use this command, you also need to have the black wire in the supplied radio cable hooked up.

STArt

n

Use the START command to choose the ASCII (0-127) character you want to use to restart output from
the PK-12 to your computer after it has been halted by entering the STOP character.

See XFLOW.

NOTE:

Default: $11 ( CTRL-Q)

PK-12 Packet Controller Operating Manual / 45

STOp

n

Default: $13 (CTRL-S)

Use the STOP command to select the character you’ll use to stop output from your PK-12 to your com-

puter. Valid entries are any ASCII character from 0 to 127.

See the XFLOW command.

TBaud

n

Default: 1200 baud

Set TBAUD to specify the terminal baud rate to be activated at the next power-on or RESTART. Be sure

you can set your computer and its communications program for the new rate.

TClear

TCLEAR clears your PK-12’s transmit buffer and cancels any further transmission of data except for a

few remaining packets.

You must be in the Command mode to use TCLEAR.

TRACe ON|

OFF

Default: OFF

TRACE activ ates the AX.25 protocol display. With TRA CE ON, all received frames are displayed in their

entirety, including all header information. The TRACE display is shown as it appears on an 80-column

display. The following monitored frame is a sample:

KB6IUX*>TESTER <UI>:
This is a test message packet.

Byte Hex Shifted ASCII ASCII

000: A88AA6A8 8AA460AE 6494AAA0 406103F0 TESTER0KB6IUX0.x ......‘.d...@a..

010: 54686973 20697320 61207465 7374206D *449.49.0.:29:.6 This is a test m

020: 65737361 67652070 61636B65 742E0D 299032.80152:.. essage packet...

The byte column shows the offset into the packet of the first byte of the line. The hex display column

shows the next 16 bytes of the packet, e xactly as received, in standard hex format. The Shifted ASCII col-

umn decodes the high-order seven bits of each byte as an ASCII character code. The ASCII column de-

codes the low-order seven bits of each byte as an ASCII character code.

Trans

TRANS switches the PK-12 from the Command mode to Transparent mode; the current state of the radio

link isn’t affected. Transparent mode is pr imarily useful f or computer communica tions since Transparent

mode “human interface” features such as input editing, echoing of input characters, and type-in flow con-

trol are disabled.

• Use Transparent mode for transferring binary or other non-text files.

• To exit the Transparent mode, type the COMMAND character, (CTRL-C), three times within the time
period set by CMDTIME (default:1 second).

TIme n Default: $14

“n” 0 to $7F (0 to 127 decimal) specifies an ASCII character code.
The TIME command specifies which control character sends the time-of-day in the text you type into the

transmit buffer or into a text file stored on disk.

46 / PK-12 Packet Controller Operating Manual

At transmit time, the PK-12 reads the embedded control code (default <CTRL-T>), reads the time-of-day
from the PK-12’s internal clock and then sends the time to the radio in the data transmission code in use
at that time. If the DAYTIME has not been set, a control-T will cause the PK-12 to send an asterisk (*).
When DAYSTAMP is set ON, the date is transmitted with the time.

Note: The TIME command cannot be embedded in CTEXT, BTEXT, MTEXT or AAB.

TRFlow ON|

OFF

Default: OFF

TRFLOW is used to set the software flow control between the PK-12 and your terminal when the PK-12
is in Transparent mode.

With TRFLOW OFF, only “hardware” flow control (RTS, DTR) is available to the computer w hen re­ceiving data from the PK-12 (while in Transparent mode).

With TRFLOW ON, the type of flow control used by the computer receiving data in the Transparent
mode is determined by how START and STOP are set. If START and STOP are set to values other than
zero, software flow control is enabled for your computer. The PK-12 responds to the START and STOP
characters, while remaining transparent to all other characters from the terminal.

TRIes

n

Default: 0

TRIES retrieves (or forces) the count of “retry counter” on the data channel presently selected.
If you type TRIES without an argument, the PK-12 returns the current number of tries if an outstanding

unacknowledged frame exists. If no outstanding unacknowledged frame exists, the PK-12 returns the
number of tries required to get an acknowledgment for the previous frame.

If you type TRIES with an argument, the “tries” counter is forced to the entered value (0-15). Using this
command to force a new count of tries is not recommended.

TXdelay

n

Default: 30 (300 mS)

TXDELAY tells your PK-12 how long to wait before sending packet frame data after keying your
transmitter’s PTT line. TXDELAY is programmable from 1 to 1.2 seconds in 10 millisecond increments.

All transmitters experience a certain length of time from the instant the PTT line is keyed to when the sig­nal is actually transmitted. The default value of 300 mS should work with almost all transceivers. In fact,
many of the newer transceivers can use smaller TXDELAY values. (Crystal-controlled transceivers can
often use smaller values as well.) On the other hand, tube-type transceivers and amplifiers can require a
longer time to switch and may require TXDELAY to be increased.

TXFlow ON|

OFF

Default: OFF

With TXFLOW ON, the setting of XFLOW determines the type of flow control used in the Transparent
mode by the PK-12 to control transmitted data; with it OFF, the PK-12 uses only hardware flow control
to control transmitted data. All data that’s sent to the terminal remains fully transparent.

With both TXFLOW and XFLOW ON, the PK-12 uses the Start and Stop characters (set by XON and
XOFF) to control the input from the computer.

UBit n ON|

OFF

Default: 0

UBIT is an extension of the CUSTOM command which allows up to 255 ON|OFF functions to be added
to the PK-12 without burdening you with a large number of extra commands. The functions controlled by
UBIT aren’t things that you’ll most likely change—still, they’re important enough to some users or appli­cation programs that we have included them under the umbrella command of UBIT.

PK-12 Packet Controller Operating Manual / 47

The following are examples of how to use the UBIT:
UBIT 5 Shows the present status of UBIT 5
UBIT 1 ON Sets the function controlled by UBIT 1 to ON
UBIT 10 T Toggles the state of the function controlled by UBIT 10
UBIT Returns the state of the last UBIT value that was accessed
Listed below are the UBIT functions and the default states that presently have been assigned. The default

state of each UBIT is shown first.

UBIT 0: Not valid in the PK-12.

OFF: The PK-12 will receive a packet regardless of the DCD status.

UBIT 1: OFF: Entering the command MONITOR ON or MONITOR YES causes the MONITOR

command to be set to 4.

ON: Entering the command MONITOR ON or MONITOR YES causes the MONITOR

command to be set to 6.

UBIT 2: ON: A Break signal received on the RS-232 line forces the PK-12 into Command mode

from all the modes except Host mode.

OFF: A Break signal on the RS-232 line is ignored by the PK-12.

UBIT 3: OFF: Multiple connect packet channels are numbered from 0-9.

ON: Multiple connect packet channels are numbered A-J.
UBIT 4: Not used.
UBIT 5: OFF: The PK-12 will always power up in Command mode.

ON: The PK-12 will remain in the last mode (Converse, Command or Transparent) pro-

vided the battery jumper is enabled.

UBIT 6: OFF: In packet, monitoring is disabled when in the Transparent mode.

ON: Packet monitoring is active in the Transparent mode. MFROM, MTO, MRPT, MONI-

TOR, MCON, MPROTO, MSTAMP, MXMIT, CONSTAMP and MBX are all active.
UBIT 7-12: Not used.
UBIT 13: OFF: MailDrop connect status messages are always sent to you, regardless of the setting of

MDMON.

ON: Remote user dialog and Connect status messages with the MailDrop are shown only if

MDMON is ON.
UBIT 14: OFF: In packet, the transmit buffer for data sent from the computer to the PK-12 is limited

only by available memory.

ON: In packet, the serial flow control will permit only a maximum of seven I-frames to be

held by the PK-12 before transmission. This solves a problem with the YAPP binary

file transfer program which relies on a small TNC transmit buffer to operate correctl y.
UBIT 15-17: Not used.
UBIT 18: OFF: The FRACK (or FRICK, if enabled) timer is used to retry packets that weren’t ac-

ON: A Master/Slave relationship is established when a packet connection is made. This is

knowledged.

designed for meteor scatter operation and is described in detail under the FRICK com-

mand and Chapter 5 - Packet Operation.

48 / PK-12 Packet Controller Operating Manual

UBIT 19-21: Not used.
UBIT 22: ON: The PK-12 will respond to the receipt of an UNPROTO frame addressed to QRA by

sending an UNPROTO ID packet frame within 1 to 10 seconds. This feature is com­patible with TAPR’s ANSWR QRA command.

OFF: The PK-12 doesn’t respond to UNPROTO frames addressed to QRA.

UBIT 23+: Reserved for future expansion.

Unproto call1[VIA call2(,call3...,call9)] Default: CQ

call1 Call to be placed in the “To” address field.
call2-9 Optional digipeater call list; up to eight calls.

UNPROTO sets the digipeat and destination address fields of packets sent in the unconnected (unproto­col) mode.

Unconnected packets are sent as Unnumbered I-frames (UI frames) with the destination and digipeat
fields taken from call1 through call9 options. When a destination isn’t specified, unconnected packets are
sent to CQ.

Unconnected packets sent from other packet stations can be monitored by setting MONITOR to a value
greater than “1” and setting MFROM to ALL.

The UNPROTO path and address is also used for beacon packets.

UPlink call1

Use the Uplink command to initiate a DAMA connection. Refer to the Packet chapter for an explaination
of DAMA. After a connection is established, your station will be a slave and will not send any informa­tion packets until it is polled by the Master.

You can type UPlink (without any parameters) at any time to check the PK-12’s connect status. If you’re
in the process of trying to connect to another station, you’ll see the message:

Link state is: CONNECT in progress

If the other station doesn’t ack your connect request after the number of tries set with RETRY, the con­nect attempt is cancelled. Your monitor would display:

cmd:*** Retry count exceeded
*** DISCONNECTED:

USers

n

call1

Default: 1

USERS affects the way that incoming connect requests are handled. It doesn’t affect the number of out­going connections you initiate. For example:

USERS 0 Allows incoming connections on any free channel.
USERS X Rejects incoming connections if there are connections on ‘X’ or more channels.
...and so on, through USERS 10.

WHYnot ON|

OFF

During packet operation, the PK-12 may receive many packets that aren’t display ed. Turning WHYNOT
ON will cause the PK-12 to generate a message explaining the reason why the received packet wasn’t
displayed. The messages and their meanings are:

Default: OFF

PK-12 Packet Controller Operating Manual / 49

PASSALL: The received packet frame had errors, and PASSALL was OFF, preventing

the packet from being displayed to the screen.

DCD Threshold: The DCD LED was off when the packet was received.
MONITOR: The MONITOR value was set too low to receive this frame.
MCON: MCON was set too low to receive this type of frame.
MPROTO: MPROTO was set to OFF, and the received packet was probably a NET/ROM

or TCP/IP frame.

MFROM/MTO: The frame was blocked by the MFROM or MTO command.
MBX: The call sign of the sending station doesn’t match the call sign setting in the

MBX command.

MBX Sequence: The frame was received out of sequence, probably a retry.
Frame too long: Incoming packet frame longer than 330 bytes. Probably a non-AX.25 frame.
Frame too short: Incoming packet frame shorter than 15 bytes. (Only seen if PASSALL is

ON—probably noise.)

XFlow ON|

OFF

Default: ON

With XFLOW ON, software flow control is in effect—it’s assumed that the computer will respond to the
PK-12’s Start and Stop characters defined by the XON and XOFF commands. Similarly, the PK-12 will
respond to the computers start and stop characters defined by START and STOP.

With XFLOW OFF, the PK-12 sends hardware flow control commands by way of the CTS line and is
controlled by either the RTS or the DTR line.

XMITOk ON|

OFF

Default: ON

XMITOK is used to enable and disable actual transmitter keying. With XMITOK OFF, your PK-12 will
generate and send data as requested, but it won’t key your radio’s PTT line. Turning XMITOK OFF can
help enable full break-in CW operation (QSK) on certain transceivers.

Xoff

n

Default: $13 (CTRL-S)

Use XOFF to select the Stop character to be used to stop input from the computer to the PK-12. Any
ASCII character from 0 to 127 may be used.

The Stop character default value is (CTRL-S) for computer data transfers.

XON

n

Default: $11 ( CTRL-Q)

XON selects the PK-12 Start character that is sent to the computer to restart input from it to the PK-12.
Any ASCII c haracter fr om 0 to 127 may be used.

The Start character default value is (CTRL-Q) for computer data transfers.

50 / PK-12 Packet Controller Operating Manual

PK-12 Command Quick Reference

COMMAND DEFAULT FUNCTION
3Rdparty
8Bitconv
ACKprior
ACRDisp
ACRPack
AFilter
ALFDisp
ALFPack
AUdelay
AUTOBaud
AWlen
Ax25l2v2
AXDelay
AXHang
BBSmsgs
Beacon
BKondel
BText (
CALibrat Starts PK-12 AFSK tone calibrate mode.
CANline
CANPac
CASedisp
CBell
CFrom
CHCall
CHDouble
CHeck
CHSwitch
CMdtime
CMSg
CODe
COMmand
CONMode
Connect Sends a packet connect request to (call).
CONOK
CONPerm
CONStamp
CONVerse Enters the Converse mode (Abbreviated “
CPactime
CStatus Shows status of channels (links).
CText
CUstom
DAYStamp
DAytime
DCdconn
DELete
DFrom
DIGIPEAT
Disconne Sends packet DISC request to distant station.

OFF
OFF
OFF
0
ON
OFF
ON
OFF
2 (20 mS

) Sets delay before audio is applied after PTT.

OFF
7
ON
0 (00 mS)
0 (000 mS)
OFF
EVERY 0
ON

Empty

) Sets the 120-byte packet BEACON message text.

$18

(CTRL-X) Sets the LINE DELETE character for editing.

$19

(CTRL-Y) Sets the PACKET DELETE character for editing.

0 (as is

) Sets the display case (as is/lower/UPPER).

OFF
ALL
OFF
OFF
30
$00
10
OFF
6
$03

(CTRL-C) Sets the Command mode escape character.

CONVERSE

ON
OFF
OFF

OFF

None
$0A15
OFF
None
OFF
OFF
ALL
ON

Enables 3rd party MailDrop messages.

Enables 8-bit data in packet Converse.

Enables priority acknowledgment in packet.

Sets terminal output screen width.

Adds (RETURN)’s to transmitted packets.

Enables all-mode receive character filter.

Sends <LF> after (RETURN) to terminal.

Sends <LF> after (RETURN) in transmitted packets.

Enables Autobaud routine at every power-on.

Sets ASCII word length to RS-232 terminal.

Sets AX.25 Version 2.0 packet protocol.

Specifies the waiting period, in addition to TXDELAY, after keying the transmiter.

Used when sending packets through a repeater with a hang time greater than 100 mS.

Enables TAPR style status messages.

Sets the packet beacon timing (x10 seconds).

Sends <BS> <SP> <BS> for DELETE character.

Enables packet connection notification.

Sets the Connect request/accept list.

Shows call sign after packet channel ID.

Shows CHSWITCH character twice.

Sets Idle packet link time-out (x10 seconds).

Sets the channel-select character.

Sets the Transparent Mode escape time.

Sends CTEXT message to packet caller.

Avoids the use of square brackets in packet headers.

Selects the mode used when data link starts.

Allows others to connect (TAPR).

Selects a permanent connection packet link.

Marks connections with time/date stamp.

K

”).

Uses PACTIME time-out in Converse mode.

Sets 120-byte packet Connect message text.

(Use UBIT instead).

Includes DATE in time-stamp.

Set or read the internal time-of-day clock.

Sets RS-232 Pin 8 to follow DCD or Connect.

Uses DEL ($7F), not (BS) ($08) to erase.

Sets the digipeat “yes or no” call sign list.

Allows digipeating (TAPR).

PK-12 Packet Controller Operating Manual / 51

DISPlay Shows the PK-12’s parameters and arguments.
DWait
Echo
EScape
EXPert
Flow
FRack
FREe Displays available memory for MailDrop.
FRIck
FUlldup
GENDchar
GINIText
GLOCtx
GNMEA1
GNMEA2
GPOLLCal
GPSAuto
GPSMode
GREMprog
GSYMChar
GUNSTart
GUsers
HEAderln
HId
HOMebbs
HOST
HPoll
Id Sends an ID packet.
ILfpack
K Enters the Converse mode (same as CONVerse).
KILONFWD
KIss
LAstmsg Sets/shows the last MailDrop message number.
LOWPow
MAildrop
MAXframe
MBEll
MBx
MCon
MDCheck Allows you to check into your own MailDrop.
MDigi
MDMon
MDPrompt (
MFIlter
MFrom
MHeard Displays call signs heard.
MId
MMsg
Monitor
MProto
MRpt
MStamp

16
ON
OFF
OFF
ON
5

0
OFF
$0D
None
0
$GPGLL
None
None
OFF
0
OFF
0
OFF
n
ON
OFF
None
0 (OFF

) Enables Host computer interface.

ON

ON

ON
0 (OFF

) Starts the KISS TNC host protocol.

OFF
OFF
4
OFF
none, (calls
0 (zero

) Monitors packet channel without headers.

) Monitors packets while connected (0-6).

OFF
OFF

see text

) Sets an 80 character MailDrop message prompt.

$80
ALL (calls

) Monitors packets from other packet stations.

0
OFF
4 (UA DM C D I UI
OFF
ON
OFF

Sets the delay for digipeated packets.
Echos typed keyboard characters.
Sends ESC character $1B to display as $24.
Selects whether or not seldom-used commands are displayed.
Stops displaying received data while typing.
Sets time (X1 sec) to wait for packet

Sets timer for packet meteor scatter mode.
Enables full-duplex packet operation.
Requires the string to end with a CR,LF to conform to the NMEA format.
Sends text to the serial port when the PK-12 is powered up.
Setsthe transmit interval for GPS data received on the serial port.
Sets the string the PK-12 will parse from the NMEA device.
Sets the second string the PK-12 will parse from the NMEA device.
Sets the callsign to any callsign other than the one already programmed in the PK-12.
Allows PK-12 to automatically detect a connected GPS receiver.
Selects a mode of operation specific to GPS.
Allows the PK-12’s GPS commands to be remotely programmed.
Sets the APRS symbol to be transmitted.
Allows the PK-12 to power-up in the converse mode (on) or in command mode (off).
Sets the number (0-3) of users allowed to use your node.
Inserts (RETURN) after monitored packet headers.
Sends HDLC ID UI packet every 9.5 minutes.
Sets call sign of the BBS for forwarding.

Sets Host polling be used in Host interface.

Ignores line feeds from terminal.

Kills messages after reverse forwarding.

Enables LEDs to function.
Enables the Packet MailDrop for remote users.
Sets a maximum of un­Rings bell when a particular packet station is heard.

Monitors packet frames that you digipeat.
Monitors stations using your MailDrop.

Filters received ASCII characters.

Enables a Morse ID to be sent in packet.
Enables the MailDrop sign on message.

) Sets the packet Monitor mode level (0-6).

Enables monitoring of all packet protocols.
Shows digipeaters in packet headers.
Time-stamps monitored packet frames.

acked

ack

packet frames.

.

52 / PK-12 Packet Controller Operating Manual

MTExt (
MTo
MXmit
MYAlias
MYCall
MYGate
MYMail
NEwmode
NOmode
NUCr
NULf
NULLs
PACLen
PACTime
PARity
PASs
PASSAll
PErsist
PK Permits access to memory locations.
PPersist
RAWhdlc
REDispla
REINIT Reinitializes the PK-12, but preserves the contents of the MailDrop.
RELink
RESET Resets PK-12 and bbRAM to factory defaults.
RESptime
RESTART Restarts PK-12; same as turning the power off/on.
REtry
SEndpac
SLottime
SQuelch
STArt
STOp
TBaud
TClear Clears the transmit buffer (Non-packet modes).
TIme
TRACe
Trans Enters the Transparent data mode.
TRFlow
TRIes
TXdelay
TXFlow
UBit
Unproto
Uplink Call 1 Used to initiate a DAMA connection.
USers
WHYnot
XFlow
XMITOk
XOff
XON

see text

) Sets a 120 character MailDrop sign-on message.

Empty; enter calls
OFF
None
PK12
None
None
ON
OFF
OFF
OFF
0 (zero

) Sets the number of NUCR and NULF.

128
AFTER 10
3 (even

) Sets the terminal program parity (0-3).

$16

(CTRL-V) Sets the converse mode pass character.

OFF
63

ON
OFF
$12

(CTRL-R) Re-displays current terminal input buffer.

OFF

0

10
$0D

(CTRL-M) Sets the converse mode “Send packet” character.

30
OFF
$11

(CTRL-Q) Sets character to start sending terminal data.

$13

(CTRL-S) Sets character to stop sending terminal data.

1200 baud

$14

(CTRL-T) Inserts the time (in DAYTIME) in text.

OFF

OFF
0 (zero

) Displays or forces packet retry counter.

30
OFF
0
CQ

1
OFF
ON
ON
$13

(CTRL-S) Sets character to stop sending received data.

$11

(CTRL-Q) Sets character to start sending received data.

Monitors packets to other station call signs.

Monitors transmitted packet frames.

Sets the alternate MYCALL for digipeating.

Sets

your

packet call sign.
Sets your node call sign.
Sets your MailDrop’s call sign.
Returns to Command mode at disconnect.
Sets no mode changes (e.g.. cmd: to CONVERSE).
Sends Nulls to terminal after (CR).
Sends Nulls to terminal after (LF).

Sets the number user data bytes in a packet.
Sets the packet automatic transmit timer.

Ignores CRC in receiving packets (Junk mode).
Sets the P-persistent CSMA threshold.

Selects P-persistent CSMA operation.
Starts Raw HDLC mode.

Re-connects after link fails due to retries.

Sets the minimum delay before sending an

Sets the maximum number of packet repeats.

Sets the P-persistent CSMA slot time.
Sets the receiver squelch carrier polarity.

Sets the terminal data rate.

Enables a Hex dump of received data.

Enables software flow control RX in Transparent mode.

Sets the PTT key-to-data delay (x10 mS).
Enables software flow control TX in Transparent mode.
Controls seldom used ON/OFF commands.
Sets the UI packet frame sending path/address.

Sets allowed number of packet multi-connects.
Displays reason why packet not displayed.
Sets Software (XON/XOFF) RS-232 flow control.
Allows transmitter PTT line to be keyed.

ack

.

5. P ac ket Operation

Overview

In the brief time that packet radio has been around, it has grown to become the most popular digital mode
found on the amateur bands today.

The Packet Modes

In packet, there are four modes available to you: Command, Converse, KISS, and Transparent.
Command mode is the launch point from where you’ll jump into packet. It’s here you enter commands to

customize the PK-12 to your needs and it’s from here you will enter the command to “connect” (chat)
with someone in the Converse mode or monitor passing traffic. Even while you’re connected with some­one, you can return to the Command mode to change commands and perform other functions.

PK-12 Packet Controller Operating Manual / 53

The Converse mode is exactl y that—a mode which you call CQ, br oadcast messages, and converse with
other packeteers.

The KISS mode is used primarily for TCP/IP packet networking. Although not used for “normal” packet
operation, it is used if you are part of a network; you’ll need to have your PK-12 and radio up and run­ning continuously. KISS is explained in Chapter 4.

Finally , there’s the Transparent mode. This mode is reserved for binary file transfers. This will be cov e red
briefly later in this chapter.

Tuning in Packet Stations — VHF/UHF

First, enter your call sign using MYCALL. For example, if your call sign is WF7A, then you’d enter:

cmd: MYCALL WF7A
MYcall was PK12*
MYcall now WF7A
cmd:

*or AAA if you just came fr om the Cha pter 2.
If you know there is packet activity in your area, but don’t know the frequencies, try some of these:
2 meter (144-148 MHz): 144.91, 144.93, 144.95, 144.97, 144.99, 145.01, 145.03, 145.05,

145.07, 145.09.

1.25 meter (222-225 MHz): 223.40, 223.42, 223.44, 223.46, 223.48
70 cm (420-440 MHz): 440.975, 441.000, 441.050, 441.025, 441.075

You’ll know you’ve found a packet channel when you hear the characteristic “braaaaaap” of packet
transmissions. If you’ve made the correct connections and your radio’s audio level is set properly, packets
should scroll up on your screen. Some typical packets you might monitor are shown below:

N7ALW*>WA7GCI [C]

PK-12 Packet Controller Operating Manual / 54

WA7GCI*>N7ALW (UA)
N7ALW*>WA7GCI:

Hi Bob, how are you this evening?
K6RFK>N7ALW*>N7GMF:

Good night John, it has been nice talking to you.

You might hear data (packets) which don’t print on your screen. This is normal and is a function of the
MONITOR and MPROTO commands.

What It Means

There are different types of packets that mean different things to your PK-12—it keeps tr ack of and
knows what to do with all these packets so you don’t have to worry about them most of the time. Since
the PK-12 has the capability of monitoring all the packet activity on a channel, it would be wise for you
to observe what scrolls up on the screen for awhile to see how stations interact with each other.

Examine the first packet exchange in the examples above:

N7ALW*>WA7GCI [C]
WA7GCI*>N7ALW (UA)

NOTE:

The first call sign is the originator of the packet. The call sign after the “>” is the station the packet is ad­dressed to. Therefore, the packet listed above originated from N7ALW and is being sent to WA7GCI. The
“[C]” immediately following the two call signs identifies this packet as a connect request. So, N7ALW is
trying to connect with WA7GCI.

The second packet, WA7GCI*>N7ALW (UA), is in response to N7ALW’s connect request—WA7GCI
responded to N7ALW with a “(UA)” which stands for Unnumbered Acknowledge; WA7GCI sent
N7ALW an ack signal as if to say, “Yes, I acknowledge getting your packet for a connect request.”

The next packet is data (text) sent from N7ALW to WA7GCI.

N7ALW*>WA7GCI:
Hi Bob, how are you this evening?

The stations are connected and are enjoying a QSO.
One benefit of packet radio is that packets can be relayed, or digipeated. In fact, packets can be “digied”

by up to eight other stations to get them to a distant station you can’t reach directly. In pr actice, digipeat­ing through a large number of stations doesn’t work well, but still you will often see packets that are digi­peating through one or two stations to get to their destination. The packet shown below is an example of
a digipeated packet:

K6RFK>N7ALW*>N7GMF:
Good night, John—it has been nice talking to you.

This packet originated from K6RFK and is intended N7GMF, but for one reason or another, it’s being di­gipeated through N7ALW. Notice the asterisk (*) in the first line—it tells you which station was actually
heard by N7GMF when it received the packet. In this case, we can see that we actually heard radio sta­tion N7ALW. Without the asterisk, you couldn’t tell whether the transmission came from radio station
K6RFK or N7ALW. More will be discussed about digipeating later, but the above example is typical.

The next packet:

K6RFK>N7ALW*>N7GMF [D]

PK-12 Packet Controller Operating Manual / 55

. . . is again from K6RFK to N7GMF and is being digipeated through N7ALW. T his packet indicates that
K6RFK has finished talking to N7GMF and wants to disconnect. Again, you see that you aren’t hearing
K6RFK directly, but N7ALW as indicated by the asterisk (*) after his call.

N7GMF>N7ALW*>K6RFK (UA)

This packet is an ack that lets K6RFK know that N7GMF has ac ked the disconnect request. K6RFK and
N7GMF are no longer connected.

The following packet is a BEACON packet from KD7NM.:

KD7NM*>MAIL:
Mail for: K6RFK N7ML WO6P

Since the packet is addressed to “MAIL” we can assume KD7NM is a Packet Bulletin Board System
(PBBS) broadcasting to the area that there’s mail waiting for these three stations to read.

The following BEACON packet is an identification packet from a NET/ROM level-3 packet networking
switch.

WN7ANK-8*>ID:
NET/ROM 1.3 (SEA)

In this example, the packet “switch” is operated by WN7ANK-8, but it uses the alias SEA as a MY­ALIAS call sign. There are many types of packet switches now in use, but NET/ROM is one of the most
popular. We will briefly discuss using a NET/ROM switch later in this chapter since most switches oper­ate in much the same way.

The packet below was sent by the network switch SEA to N7ML.

SEA*>N7ML:
SEA:WN7ANK-8> Connected to #SEA:N7HWD-7

This message tells N7ML that he is now connected to another port on the SEA “node” named #SEA.
Again, we will talk more about how and why N7ML might want to do this later in the chapter.

Who’s Out There?

If you don’t have a friend on packet in your local area, then you will want to choose a station you can
reach. Fortunately the PK-12 has a command called MHEARD that displays the list of the last eighteen
stations it has heard.

After you’ve tuned to a packet sta tion for half an hour or so, enter MHEARD at the command prompt.
You’ll see something like this:

cmd:MHeard

........ WO6P

........ KB6IUX-1

........ SEA*

cmd:
cmd:MHeard (with DAYSTAMP ON)

21-Nov-93 13:40:35 WO6P
21-Nov-93 13:40:25 KB6IUX-1
21-Nov-93 13:40:01 SEA*
cmd:

The call signs in the list are the stations heard by your PK-12 with the most recently heard station at the
top of the list. As mentioned earlier, the asterisks (*) indicate that the station was heard directly by the

PK-12 Packet Controller Operating Manual / 56

PK-12. The call signs without an asterisk were relayed by another station and so cannot be connected to
you directly without connecting to a node or digipeating.

Talking to Yourself

Most of us are a little nervous when we first get on-the-air in a new mode. In packet, fortunately, you’re
able to get a lot of practice just by talking to yourself before you send your first CQ or connect to some­one else who has sent a CQ. Once you feel comfortable with the basic operation of packet, going on-the­air is a breeze! To get some practice, you can learn the important commands by talking to y our self .

Remember the “loop-back” test back in Chapter 2, where you tied the green and white wires together at
the end of the radio cable? You’ll do roughly the same thing here. First, remove the RADIO cable. Then,
cut a short length of any single-conductor wire that may be lying around your shack and insert one bare
end into Pin 1 of the RADIO port and the other bare end into Pin 4. With your communications program
and PK-12 running so that the cmd: prompt is displayed, you’re now all set to have a thrilling mono­logue.

Connecting

When you want to chat with a station in packet, you “connect” to it. The abbreviation of the CONNECT
command is the letter, C. Go ahead and connect to yourself by entering: C your call. If your call happens
to be KB6IUX, you’ll type:

cmd:C KB6IUX
*** CONNECTED to KB6IUX

You have now changed from the Command mode to the Con verse mode—the CON (CONnected) light is
lit on the PK-12’s front panel. Go ahead and type a quick sentence and press (RETURN). Your sentence
will echo back at you. If you were the receiving station, the echo you see is exactly what would appear on
your screen. Type in another sentence, but this time as you press (RETURN), watch the PK-12’s front
panel. The XMT and STA lights come on, then the XMT light will go out. A few moments later, the
XMT light will come on briefly, then both the CON and STA lights will go out.

What’s happening here? It’s all part of packet’s error-checking scheme. When you pressed (RETURN),
the XMT light came on because the PK-12 was keying up your transmitter and sending your packet to
the other station. Once the packet has been sent, the XMT light goes out and your transmitter unkeys. The
STA light stays on because the PK-12 is waiting for the packet you just sent to be acknowledged (acked)
by the receiving station. After the other station receives your packet and checks it over to see that it was
received okay, it sends back a quick ack signal. When your PK-12 receives the other station’s ack signal,
it “acks the ack”; your transmitter is momentarily keyed f or this to ha ppen.

Leave the Conv erse mode by entering a (CTRL-C). Now you’re back in the Command mode. Notice that
the CON light is lit—this is because you’re still connected with a station. When you enter a (CTRL-C)
while you’re connected, you’ve essentially put the other station “on hold” like you would with a tele­phone—you can go do anything that you can normally do while in the Command mode.

You have a couple of options now: you can either return to the Con v erse mode and continue chatting with
the other station, or you can disconnect—which ends the QSO. To go back to the QSO enter the letter
K—for “K”onverse—next to the cmd: prompt. You’ll be put on a new line and will be able to type text
or read what may have come up on your screen in your absence. While in the Command mode, if you de­cide to end the connection, enter the letter D, for Disconnect. In this example with KB6IUX, you’d see:

*** DISCONNECTED: KB6IUX
KB6IUX*>KB6IUX (UA)

CTEXT

PK-12 Packet Controller Operating Manual / 57

Congratulations! You performed the basic steps you need to initiate and end a basic packet contact. Try
this exercise a few more times until you feel comfortable with it. When you are, remove the jumper from
the RADIO port and reinsert the radio cable.

A step you might want to take right now is to enter a CTEXT message. CTEXT is like a telephone an­swering machine message (up to 120 characters) that your PK-12 will send to a station immediately after
it connects to you. A good CTEXT message is something like this:

cmd: CTEXT Hi, there! If I don’t respond in a few moments to your connect, please leave a message
in my mailbox, WO6P-1. Thanks! (RETURN)

CText was
CText Hi, there! If I don’t respond in a few moments to your con-

nect, please leave a message in my mailbox, WO6P-1. Thanks!
cmd:

With this message, the connected station has the option of waiting for you to “pick up the phone” or to
leave a message in your MailDrop.

To enable your CTEXT message, turn CMSG ON. If you don’t want your PK-12 to send the message,
leave CMSG OFF.

When you first turn on your PK-12, it becomes a standard AX.25 packet TNC (Terminal Node Control­ler). When you connect to a TNC, in most cases you’ll be connecting directly to someone’s computer
screen. If you get a message like this . . .

Welcome to my packet station. If I don’t respond, please leave a
message and Disconnect.

. . . when you connect to another station, usually you would type something like “Hello?” If you don’t see
a response from the other station in a minute or so, simply leave a message—just like a telephone answer­ing machine. The TNC at the other station should then hold your message until the operator returns to the
computer or terminal. However, if the other operator shuts off their computer before checking the screen,
then your message will never be seen. So if the other operator doesn’t answer after waiting a reasonable
amount of time, try to connect to their mailbox.

Connect/Disconnect Notification (CBELL)

If you’re in the shack but doing other things—or while you’re connected to a station—you may want to
be alerted when someone else connects to you. Turning CBELL ON will make your computer beep three
times when another station connects or disconnects from you.

Setting Up for Transmitting

If you’re using a Timewave program, follow the instructions in the program’s manual.
Most packet operation is on FM simplex. Turn off the repeater offset in your radio if it’s on.

PK-12 Packet Controller Operating Manual / 58

Calling CQ

In order to allow amateurs to send message beacons and to call CQ, the AX.25 protocol has the a bility to
send packets that are intended for more than one specific packet station. Since all packets m ust have a
destination call sign, the PK-12 sends Unprotocol packets to the call sign of CQ. This can be changed
with the UNPROTO command, but most people like this since it makes an easy way to call CQ. You can
call CQ in one of three ways: locally, by digipeating, or thr ough a node.

Locally: Simply enter K to enter the Conve rse mode, press (RETURN) twice, then (CTRL-C) to return to
the Command mode. Your CQ will look like this to anyone that’s monitoring you:

(your call)*>CQ:

If you wanted to digipeat your CQ, say through WF7A, you’d enter it like this:

U CQ V WF7A (RETURN) (RETURN) (CTRL-C)

To listeners nearby, they’ll see this on their screens:

(your call)>WF7A*>CQ:

...or if they hear your call directly, it’d be:

(your call)*>WF7A>CQ:

You can use up to eight calls in a “path” to send your CQ through a distant station.
To change the UNPROTO command to read something other than CQ, enter: UNPROTO (text), with

(text) being up to six characters long.
Nodes usually have a CQ command. To call CQ through the node, you’d connect first and then enter

CQ—the node will send your call sign out for you.
To send a CQ through a couple of nodes to a distant one, you’ll have to connect to each node as described

in the Digipeating section below.

Going On the Air

Choose one of the stations with an asterisk displayed in your MHEARD list, or a friend that you know is
on the air near you, and enter:

cmd: C call

A few moments later, you should see:

*** CONNECTED to

If you see this, you have just connected to your first packet station! Since you initiated the contact, you
speak first. As you type, you may notice that the XMIT light on the PK-12’s front panel comes on. This
means you’ve typed in a PACLEN’s worth of text and the PK-12 is sending it; just keep on typing until
you’ve finished with your messag e. After you’ve finished typing, enter a couple of (RETURN)’s or press
the “greater than” sign (>), followed by a (RETURN), to let the other station know that you’ve finished
typing and that it’s their turn to transmit. The other station will respond—a PACLEN’s worth of charac­ters at you at a time—then will give you a couple of (RETURN)’s or a “>” to signal you to start transmit­ting. This is how it goes, back and forth, until you’ve finished chatting. Terminate the QSO as you did
before with a (CTRL-C)+(CTRL-D).

call

I’m Having Trouble Connecting

If the station you’re trying to connect to is connected to someone else, you may see the following mes­sage:

PK-12 Packet Controller Operating Manual / 59

*** BUSY

If you see this, it means that the other station is connected with someone and can’t respond to you now.
Simply wait a few minutes and try again or try connecting to a different station from your MHEARD list.

If the distant station can’t hear your station, you may see the following:

*** Retry count exceeded
*** DISCONNECTED: (call)

A number of different things can cause this to occur. It may simply be that the station you’re trying to
connect to is out of your transmitter’s range or is inaccessible for one reason or another. It’s possible,
howeve r, that something more serious is wrong. If all of your connects don’t go as smoothly as planned,
go to the packet section of Chapter 7 — Troubleshooting for assistance.

call

: DISCONNECTED

More Packet Features

Once you have worked a packet station or two, you can learn a little more about the other capabilities of
the PK-12 by reading about them in Chapter 4 — You’re In Command.

Nodes and Node Operation

In the early days of packet radio, amateurs had to “digipeat” through many stations (up to 8) to connect to
a distant station. As more users became active on packet, digipeating quickly proved to be an inefficient
way of relaying packets through even a few “hops.” The reason why is simple: with all the packets on­the-air being leapfrogged to reach their destination, they’d invariably “crash” into each other, meaning
that stations would transmit (and retransmit) packets at the same time. As you know from voice radio op­eration, when two stations talk at the same time you get a garbled mess, and that’s what happened—pack­ets would crash, stations would retransmit the packets since they weren’t acked and they’d crash again.

To solve this problem, amateurs began working on more efficient “higher level” ways of routing packets

™

over long distances. NET/ROM
that emerged and are currently in use around the world. An analogy to packet node operation is your
body: say you stub a toe against the wall. The nerve impulse starts at your toe, is transmitted by branch
nerve fibers in your leg, then on to your spine (backbone) and finally the impulse reaches its destination,
the brain. Packet communications work pretty much the same way: you (the toe) would send to a node (a
branch station) that would be retransmit along a digital backbone to a final destination. Instead of a cen­tral clearinghouse for signals like your brain, packet signals are routed along nodes that would retransmit
a message until it reaches its destination.

In practice, you’d never connect directly to a backbone station; backbone stations typically operate in the
220 MHz and 440 MHz bands (in the U.S.) and are used strictly as retransmitters of packets, not origina­tors in the usual sense. Because these stations are not used for local traffic, they can speed packet traffic
along faster and without interruption.

In summary, you don’t connect to a distant station through a bunch of other stations anymore, but to a
node, which does all the connecting and retransmitting for you. It doesn’t necessarily have to be a distant
station that you’re connecting to. In mountainous or hilly areas, it’s common practice for all stations to
connect to a node and have it retransmit the signals rather than connect directly to a nearby station. This
method helps solve the packet crash problem that you read about a few paragraphs ago.

When you connect to a NET/ROM node, you won’t initially see a prompt. Airtime is reduced because the
NET/ROM commands are not transmitted, since there are so few commands and they are easy to memo-

, ROSE, TCP/IP, and TEXNET are some of the higher level protocols

PK-12 Packet Controller Operating Manual / 60

rize. Like other automatic systems however, if you send an “H” or a “?” (for Help), you can expect to get
a response. For Seattle’s SEA node, you’d see:

cmd:

c sea

*** CONNECTED to SEA
?
SEA:WN7ANK-8} Invalid Command - Choose from :
Connect CQ Bye Help Info Nodes Routes Talk Stats BBS MHeard Users
Quit

In the above example, the Seattle node addressed as SEA is operated by WN7ANK-8. Invalid Command
means that the node didn’t understand the command a connected station sent, so it returned the above
“help” line to remind the user of the commands it knows, which are listed below its I.D.

Your PK-12’s on-board Gateway firmware supports local acknowledgment (acks) of packets like a full­service BBS/node does. Now, instead of users having to digipeat through your MYALIAS or MYCALL
call sign to connect to a destination station, they can now simply connect to your MYGATE call sign.
From there, they can issue a connect request to the station they want to reach and your station will be re­sponsible for accepting and sending packet data and acks (users can’t digipeat through your MYGATE
call sign). Users can also enter the MHEARD command to see the last 18 stations your TNC has heard.

For your node to work, simply enter a call into MYGATE—not the same one as your MYCALL, MY­ALIAS, or MYMAIL—and set GUSERS to a value greater than zero. To disable the node function, en­ter MYGATE NONE or GUSERS to zero.

With each station connected to y our node, you’ll lose a “logical” channel. If you have GUSERS set to 3
and three source sta tions have connected to three destination stations through your node, they’ll take up
six of your ten channels, leaving you with only four channels to accept and initiate contacts. (If a station
connects to your MailDrop that would leave you only three channels.)

Operating Your Node

Here’s what a user would see when using you as a packet node. In this example, your MYGATE call is
set to N7ML-7:

cmd:C N7ML-7
*** CONNECTED to N7ML-7
+++ N7ML Gateway. Type ? for help.
de N7ML-7 (B,C,D,J,L,N,S,?) >

The first line is the user’s connect request to your TNC. The second line is the connect message from the
user’s TNC. The third line is the greeting, and the fourth is the command prompt from the Gateway. The
user sends a question mark, ?, to obtain the following help menu:

B(ye) Log off gateway
C(onnect) n Connect to station ’n’
C n STAY Stay connected to gateway when ’n’ disconnects
D(isconnect) Cancel a connect attempt
J(heard) Display stations heard
L(isten) Toggle monitoring
N(odes) Display nodes heard
S(end) Broadcast unproto
de N7ML-7 (B,C,D,J,L,N,S,?) >

NOTE:

PK-12 Packet Controller Operating Manual / 61

The commands’ functions are:
B(ye) This is similar to the Bye command used in the Timewave MailDrop and BBS stations.

When a user enters a B, the Gateway will “disconnect.”

C(onnect) n Similar in operation to the CONNECT command in the packet mode.

For a packet connection, the user may connect to your Gateway, then specify a string of
digipeaters:

C W1AW VIA W2XY, W1XXZ

Your Gateway will try to establish a connection with W1AW as the destination; the
user’s call sign will be shown as the source, but with a difference: the user’s SSID is de­creased by one to avoid protocol conflicts on the same frequency.

Here is an example of the frames sent in establishing a typical connection (with the
MONITOR command set to 5):

USER>GATE [C]
GATE>USER (UA)
GATE>USER [I]:
+++ N7ML Gateway. Type ? for help.
de GATE (B,C,D,J,L,N,S,?) >
USER>GATE (RR)
USER>GATE [I]:
c remote
GATE>USER (RR) USER-15>REMOTE [C]

REMOTE>USER-15 (UA)
GATE>USER [I]:
+++ CONNECTED to REMOTE at GATE
USER>GATE (RR)
USER>GATE [I]:
hello.
GATE>USER (RR) USER-15>REMOTE [I]:

hello.

REMOTE>USER-15 (RR)

REMOTE>USER-15 [I]:

Yes?
GATE>USER [I]: USER-15>REMOTE (RR)
Yes?
USER>GATE (RR)

Once the connection is established with the destination station, the Gateway notifies the
user that the connection has been made and then goes from the Command mode into
the Converse mode. No w, whatever the user sends goes to the destination station as data
instead of to the Gateway as a command.

Normally, when someone disconnects from your Gateway, no link will remain. How­ever, if a user adds the word STAY as the last argument in a Connect request, (e.g., C
call sign STAY ), the user will remain connected to your Gateway after disconnecting
from the destination station.

PK-12 Packet Controller Operating Manual / 62

If the connect attempt to the destination station retries out or is busy, your Gateway
sends the user a Retry count exceeded or (Remote) busy message, and
remains connected to the user even if STAY wasn’t entered.

D(isconnect) (To cancel a connect attempt.) Since the source station remains in the Command mode

until the connection to the destination station is established, there’s no need for the user
to wait for your Gateway to cycle through a full number of retries to attempt a connec­tion—the user can send your Gateway a Disconnect request, which cancels the Connect
request the same way it would in a TNC’s Command mode. (The user stays connected
to your Gateway even if STA Y wasn’t used in the original Connect command.) The Dis­connect command may be used at any time before the connection is established, regard­less of any preceding commands.

Once a connection is established and your Gateway is in the Converse mode, the user
can end the connection either by sending a B(ye) command to the destination station if
that station supports it, or by issuing a Disconnect request to the user’s own TNC. If the
user disconnects from your Gateway this way, it will force your Gateway to disconnect
the destination station.

J(heard) Your Gateway sends its MHEARD list to the user. A maximum of eighteen stations are

kept in the JHEARD list. JHEARD is a command available only to stations connecting

to you.
L(isten) The Gateway toggles monitoring on or off.
N(odes) Your Gateway sends the user a list of nodes heard. The format is the same as that of the

S(end) Your Gateway responds with. . .

Digipeating

Sooner or later, you’ll want to connect to a packet station that’s beyond your immediate radio range or is
inaccessible from your location. If a third packet station is on the air and both you and the station you
want to talk to are in range of that third station, the third station can act as relay station for your packets—
you simply enter the digipeater routing path in your connect request. Here’s a sketch that shows how di­gipeating can solve a simple problem:

JHEARD command, the difference being that a call sign is put in the Nodes list only if

the monitored packet was a UI frame with a PID of CF (NET/ROM) or CD (IP). A

maximum of ten stations are kept in the Nodes list. You clear the Nodes list and the

MHEARD list simultaneously with the same command, MHEARD %.

+++ Sending. To end, type ’=’.

. . . and sends all subsequent data in the broadcast format appropriate to the selected

port’s operating mode. The data characters are held until the user sends a (RETURN),

whereupon the held data is broadcast.

In all operating modes, the user can stop sending “unproto” by sending the “=” charac-

ter—the Gateway will then issue a command prompt. The “=” character shouldn’t be

used within the user’s broadcast text.

WO6P

KB6IUX

|

/\/\/\

/\/\/\/\/\/\ KG6ZL

You’re station WO6P and y ou want to have a packet QSO with KG6ZL, but there’s a “cumulo-granite
cloud” (mountain) between you that completely blocks your radio path. However, you know that there’s
a packet station, KB6IUX, that is accessible to both you and KG6ZL located on the mountain top.

To digipeat through (VIA) KB6IUX, enter:

cmd: C KG6ZL V KB6IUX

. . . but KB6IUX doesn’t have DFROM ON, so no one can use him as a digipeater. W hat now? Pick up
the telephone and call your friend at KG6ZL? Not necessarily. You listen some more and you can hear
another station, KD7NM, off to the side of the mountain chatting with WF7A. WF7A is in a location
where you know he can reach KG6ZL. So, you enter the linear, point-to-point path you need to use to
connect to KG6ZL:

cmd: C KG6ZL V KD7NM,WF7A

They both have DFROM ON, so a few seconds later you receive an ack back from KG6ZL and you’ re all
set.

Are You a Digipeater?

Your packet station can be a digipeater for other stations. You don’t have to “do” anything—your PK-12
will digipeat other stations unless you tell it not to by using DFROM.

PK-12 Packet Controller Operating Manual / 63

If your transmitter keys when you’re not using it or during lulls in your own conversations, you’re being
used as a digipeater by someone. Don’t worry—this won’t interfere with your conversation. (As a cour­tesy, leave DFROM ON.)

To monitor the text the other stations are sending through you, set MDIGI ON.

Identifying as a Digipeater

If your PK-12 is being used as the primary digipeater in a local area, you may want to enable HID—it
will automatically identify your station for others to see.

You may also want to choose a simple identifier for others to use. You set it with MYALIAS. Examples
are: SEA for Seattle; PTLD for Portland; LYNN for Lynnwood, and so on.

Time-stamping Packets and Messages

Monitored packets can be time-stamped if the PK-12’s internal c lock has been set with DAYTIME. To
time-stamp monitored packets, turn MSTAMP ON. Turning DAYSTAMP ON adds the date to the time­stamp provided by MSTAMP.

Sometimes it is useful to know what time someone connected to you—perhaps for logging purposes. To
time-stamp your packet connects and disconnects, turn CONSTAMP ON. As discussed in the last para­graph, turning DAYSTAMP ON will add the date to this time-stamp as well. The DAYTIME command
must be set first for DAYSTAMP to operate.

Multiple Connection Operation

Because packet radio supports multiple QSOs on the same frequency, you can converse with more than
one station at a given time. The PK-12 offers ten channels, (0-9), each of which can support a conversa­tion. This capability is a powerful feature of your PK-12, and a mentally challenging one when you have
more than a couple of QSOs going on at once!

PK-12 Packet Controller Operating Manual / 64

Multiple connect operation is like a 10-line telephone with automatic “hold.” When you’re connected to
multiple stations you automatically receive everything sent to you, but you must select the proper channel
to send data to a particular station on a particular channel; in effect, it’s just like having to push the proper
“line” button on the telephone to talk to someone—you can’t talk to someone on Line 1 while you’re
talking on Line 3.

As mentioned before, you can step down to Command mode while you’re connected to someone—you’ll
need to jump down there in order to change channels. (This is true for any and all of the channels that are
active.)

The MAIL light will blink if the PK-12’s receive buffer is filled. To keep the buffer from filling up quickly
with “junk mail,” set MONITOR to zero. To clear the mail buffer, you can either turn the PK-12 off and
then on again, enter RESET, or let the PK-12’s contents “dump” into your computer.

Setting Up

You can select any channel to initiate a connect, but to enable your PK-12 to allow incoming multiple
connections, you need to set the USERS parameter to a value greater than one. The number you enter in
the USERS command tells the PK-12 how many users you’ll allow to connect to you at a given time. So,
if you set USERS 5, five stations can connect to or dig ipeat through you at the same time. With USERS
set to 0 (zero), no one can connect to or digipeat through you.

NOTE:

With all ten channels enabled with the USERS command, stations that connect with you will connect to
the PK-12’s channels in ascending order, star ting from 0. Stations that connect to your MailDrop are au­tomatically connected to your PK-12’s Channel 9.

The Channel Switching Character

Once you’ve set the USERS command, you need to set the CHSWITCH character. Set it to a character
that you don’t normally type, such as the vertical bar “|” (ASCII $7C) or the tilde “~” (ASCII $7E).
You’ll use this character to tell your PK-12 that you want to change channels. To change channels, press
the CHSWITCH character you just defined, and then a number from 0-9. For example, if your
CHSWITCH character is the tilde, you’re chatting with someone on Channel 0, and you want to chat
with a station that connected to your PK-12’s Channel 1, you’d enter:

cmd:~1 (RETURN)
~1: cmd:

Though you’ve changed to Channel 1, you can access all the commands normally available that you had
in Channel 0, the PK-12’s default channel. This is true for all ten channels.

When you change channels, the channel you changed to will have the packet header information of the
station that just connected to you. Remember that the text you’ll now type will only be sent out to the sta­tion connected to the channel your PK-12 is currently on. If, while talking on Channel 1, the station still
connected to you on Channel 0 sends data to you, it will be held in the PK-12’s memory until you return
to Channel 0, whereupon the data will scroll up on your screen.

NOTE:

NOTE:

Say, by coincidence, the station you’re connected to sends a character which is the same one you’ve set
for CHSWITCH. If you want to be able to tell the difference between the CHSWITCH characters you

type and the same character from other station, set CHDOUBLE ON. This will cause all received
CHSWITCH characters to appear double, while the ones that you type will appear only once.

CHCALL

Multiple connection operation can be confusing, especially when you’re trying to remember who’s con­nected on which channel. To help the situation, turn CHCALL ON to display the call sign of the station
connected to you on a given channel number.

Checking Your Connect Status with CSTATUS

To check whic h channels are available to you as well as who’s connected to you, enter CSTATUS. It will
show you the connect status of all 10 packet channels—connected and unconnected—including the
channel you’re currently on. By entering CSTAT SHORT, the PK-12 will display only the channels that
are currently connected.

Packet Meteor Scatter Extension

A new packet protocol extension has been added for meteor scatter work that allows a Master/Slave
packet connection to be established. This is done to reduce the possibility of simultaneous transmissions
by both sides of a packet connection over a long meteor scatter path. This experimental protocol is acti­vated by turning UBIT 18 ON. The packet station that initiates a packet connect becomes the Master sta­tion and the station that acknowledges the connect becomes the Slave.

PK-12 Packet Controller Operating Manual / 65

After a meteor scatter connection has been established, the Master station continually sends either infor­mation frames (I-frames) or polling frames and awaits an acknowledgment from the slave. The Master
station sends packets constantly, even if all its I-frames have been acknowledged. The Slave station sends
nothing, not even I-frames, until it receives a polling frame from the Master. The Slave station may only
send an I-frame to the Master after a poll frame has been received.

The packet timing of the Master station is critical for proper meteor scatter operation. In a normal AX.25
packet connection, the FRACK timer counts down until it reac hes zero and then a RETRY of a poll
frame is sent. The FRACK timer counts in units of seconds, however, and a finer timing resolution is de­sirable for meteor scatter work. A new timer, called FRICK, has been added which times in 10 mS incre­ments. The FRICK timer can be set from 0 (disabled) to 250 which corresponds to a time of up to 2.5
seconds.

The following settings are recommended for this method of meteor scatter work. Both packet stations
should use the same settings:

UBIT 18 ON
RETRY 0
AX25L2V2 ON
MAXFRAME 1 (CHECK doesn’t matter)
FRICK n, where n is large enough to allow the other station time to send the start of an acknowledg­ment frame.

NOTE:

Don’t operate the unit with multiple packet connections while FRICK is active (1-250). In contrast to
FRACK, which provides one retry timer per multi-connect channel, there is only one FRICK timer in the
PK-12. Each logical channel will try to use the same FRICK timer, causing interference with the other
channels.

PK-12 Packet Controller Operating Manual / 66

Digipeaters shouldn’t be used when in the meteor scatter mode. The FRICK timer (unlike FRACK)
doesn’t allow any extra time when digipeater stations are specif ied. To return to normal AX.25 pack et op­eration, turn UBIT 18 OFF. Also, be sure to disable the FRICK timer (by setting FRICK to 0) when
you’re through operating in meteor scatter mode.

Intermediate and Advanced Commands

Your PK-12 has many commands that are not necessary for day-to-day connects or casual conversations.
Still, as you become more familiar with packet, these commands and features may become important to
you.

Monitoring Other Stations

When you’re connected, MCON determines what pac kets are shown. The default of MCON is 0 (zero),
which tells the PK-12 not to monitor any packets while you’re connected. Most users prefer it this way , so
they’re not disturbed with monitored channel data while they’re connected with another station. However,
if you want to monitor packets while connected, refer to MCON in Chapter 4 for user settings.

Use the MONITOR command to determine what kinds of packets you’ll see when you’re not connected
to any stations. The higher the argument number (1-6), the more information you’ll see. If you don’t want
to see extraneous information associated with sent packets, use a lower value like 2 or 3.

Monitoring the Packet Networking Switches

There are other types of frames used by networking switches that the PK-12 doesn’t normally display.
These frames can be seen with MPROTO—turning it on allows all AX.25 frames to be displayed. Some
packets you might see with MPROTO ON will contain information that may interfere with the display on
your computer, causing it to look “funny”. For this reason, MPROTO’s default is OFF .

Selective Monitoring

After you’ve monitored channel activity for awhile, you may decide there are only a few stations you
want to copy. To “screen” stations f or monitoring purposes, use MTO and MFROM. With the MBELL
command, you can even be alerted when a certain station transmits on the frequency. These commands
work in conjunction with MONITOR and MCON commands.

MFILTER

Some terminals and computer programs are sensitive to certain characters that may appear in monitored
packets. You’ll know this is happening if the cursor on your screen occasionally moves to strange places
and causes the received copy to be garbled.

The PK-12 default for MFILTER is $80, which prevents most control characters from interfering with
your display.

Monitor Without Call Sign Headers

Sometimes you may want to monitor certain stations without having to look at the packet call sign head­ers. This can be useful when monitoring message traffic from a large PBBS. The MBX command allows
you to choose the call sign of a station, or a pair of stations, you want to monitor without having to see
packet headers.

Beacon Operation

In the early days of packet, the beacon was useful to show your presence on the packet channel. With the
growth of packet, many users feel that beacons have outlived their usefulness and interfere with traffic.
Use your beacon with discretion.

The PK-12 can send an automatic “beacon” message at a specified time interval. A beacon can send spe­cial announcements or just let others know you’r e on the air. To enable beacon operation:

1. Enter your beacon message in BTEXT.

2. Set the beacon interval using the BEACON EVERY or AFTER command.

3. A beacon frame is sent to the path set in UNPROTO.
As a reminder, if you set the BEACON timing at a value considered too small for busy channels (less

than “90”), you’ll see:

WARNING: BEACON too often

Packet Transmit Timing

The PK-12 has a number of built-in timers used to control the packet protocol and transmit timing. The
default values have been set at the factory, but they may not be the optimum values for your local area.
Most protocol parameters should be adjusted only after reading about them later in the chapter. You
should adjust TXDELAY for your transmitter as described below.

PK-12 Packet Controller Operating Manual / 67

Radios vary in the time it takes it to switch from receive to transmit. If your PK-12 starts sending data be­fore your transmitter is up to power, the packet will not be received properly at the distant end.
TXDELAY controls the delay between your transmitter’s key-up and the moment your PK-12 starts
sending data. The default value of 30 corresponds to a time of 300 mS and works with most VHF/UHF
FM transceivers. With modern transceivers, TXDELAY can often be reduced from its default value
which will improve packet performance. You should perform the following procedure to optimize
TXDELAY for your station:

1) Find another station who can reliably digipeat your signals.

2) Set your UNPROTO path to TEST via the call of the station that will digipeat your signals. For ex-
ample: U TEST V WO6P.

3) Set MONITOR to at least 1.

4) Go to Converse mode by entering K, then send a few packets by pressing the (RETURN) key. You
should see the outgoing packets on your own screen echoed back as they’re digipeated by the other
station.

5) Start reducing TXDELAY by units of 5 each time, making sure the other station is still digipeating
all of your UNPROTO packets.

Eventually you’ll find a value where the other station can no longer copy your packets accurately enough
to digipeat them. When this happens, increase TXDELAY in units of one or two until the other station
digipeats all of your packets again. This will be the optimum setting of TXDELAY for that particular ra-
dio.

After TXDELAY has been adjusted, you may want to adjust the audio delay (AUDELAY) using the
same procedure. (See AUDELAY in Chapter 4 for mor e information.)

PK-12 Packet Controller Operating Manual / 68

Packet Formatting and Editing

Some of your PK-12’s command par ameters affect how your packets are formatted—how your typing
appears to the rest of the world. Other commands let you correct typing errors before your packet is sent,
cancel lines, or entire packets.

(RETURN)’s and Linefeeds

Most hams use packet radio for sending and receiving messages or conversation. The character used to
send a packet is defined with the command SENDPAC which defaults to a (RETURN) ($0D). You can
change the SENDPAC character, but you’ll find the (RETURN) or (ENTER) key to be a natural choice.

Similarly, your PK-12 will include a ( RETURN) in the packet you send to the other station since this
makes for a more natural conversation. ACRPACK controls this feature, though most people will never
want to change this.

The PK-12 also has the capability of adding a linefeed character ($0A) automatically to packets that you
send to others. If you encounter a station or two that says your packets are overprinting, you may want to
turn the ALFPACK or ILFPACK ON for them.

Cancelling Lines and Packets

Most of the time, (BACKSPACE) or (DELETE) is all that’s needed to edit a line before it’s sent. Occa­sionally it may be helpful to cancel a line or the entire packet you’re entering with just one keystroke. The
CANLINE character, (CTRL-X), will cancel the entire line you’re typing; the CANPAC character,
(CTRL-Y), will delete the entire packet.

Redisplaying Text

If you’ve er ased and retyped lots of characters, you may want to see a “fresh” screen (especially if
BKONDEL is OFF). The REDISPLAY character (CTRL-R) will refresh your screen and will display
any packets you might have received while you were typing.

The PASS Character

Sometimes you may want to include a special input character, such as a (RETURN), in a packet without
forcing an action to happen. For example, to send several blank lines in the same packet, you must in­clude a (RETURN) at the end of each line. However, when you press (RETURN), it normally forces a
packet to be sent. You can get around this pr oblem using the PASS (CTRL-V) character. You can include
any character in a packet (including all special characters) by prefixing that character with the PASS char­acter. For example, if you’re in Converse mode, you can type:

I wasn’t at the meeting. (CTRL-V)+(RETURN)
What happened? (RETURN)

Without the PASS character, this message would go out as two separate packets because you entered two
(RETURN)’s, but b y prefixing the first (RETURN) with a (CTRL-V), you send all the above text in only
one packet while maintaining its two-line format. The PASS character can be useful in formatting text
messages, such as CTEXT, as well.

Packet Protocol Basics

Here we will talk a little about the AX.25 packet protocol. You don’t need to understand this to use
packet, but it is helpful in understanding some packet protocol parameters.

There are two modes of packet transmissions: connected and unconnected. Most of the time when you
use packet, you’ll be conve rsing with another packet station in a connected state. Still, the unconnected,
or unprotocol, mode comes in handy for beacon transmissions and roundtable exchanges.

All packets are constructed basically the same: they contain source and destination call signs (and any
digipeaters, if used) as well as information identifying the type of packet. (This packet identification can
be seen with the MONITOR command discussed earlier.) All packets contain an error check code called
the CRC. This ensures that it won’t contain any errors when it is received. PASSALL can disable the
CRC error check, but this should only be done for experimental purposes.

Connected Packets

When you connect to another station, the AX.25 packet protocol ensures that the station you’re connected
to receives all the packets that you send. Likewise, the protocol ensures you will receive all the packets
the other station sends to you. The following describes briefly how the protocol does this.

FRACK and RETRY

When the PK-12 sends a packet to another station, it expects an ack packet back from the other station
confirming that the packet was received. The AX.25 packet protocol will automatically retransmit (retr y)
packets when an acknowledgment isn’t received from the distant end of the link within a specified time.

FRACK sets the time span before the originating station retransmits (retries) the packet that hasn’t been
acked.

PK-12 Packet Controller Operating Manual / 69

RETRY sets the maximum number of retransmissions before your PK-12 “gives up” and terminates the
connection attempt (disconnects). The TRIES counter keeps track of the retries that have occurred on the
current packet.

PACLEN and MAXFRAME

Packets will be sent either when (RETURN) is pressed or when the maximum packet size is exceeded—
which is set by P ACLEN. When large amounts of data need to be sent, PACLEN can be increased to 256.
When conditions are poor or the channel is crowded, this value should be reduced to 64 or less.

The packet protocol allows more than one frame to be sent in a single transmission, which is set by
MAXFRAME. When conditions are good, up to 7 frames can be sent to speed data transfer. When con­ditions are poor or the channel is crowded, MAXFRAME should be reduced to 1.

Reducing Errors through Collision Avoidance

Since packet operates over the radio, there are usually many stations operating on the same frequency that
can’t hear each other. The digipeaters and network nodes allow these stations to communicate with each
other, which can increase the chances of collisions.

The first attempt to avoid collisions was through the use of the DWAIT and RESPTIME timers. DWAIT
forced the TNC to delay the transmission of any packet except for digipeated frames by the time selected.
This fixed timer helped, but packet was still plagued by collisions. RESPTIME was added to help with
large file transfers. Still, more needed to be done to reduce collisions.

Another attempt to reduce collisions was the introduction of AX.25 version 2 protocol. Almost everyone
on VHF packet uses version 2, which is controlled b y the AX25L2V2 command.

An exponentially distributed random wait method was proposed by Phil Karn (KA9Q) called P-persistent
CSMA. When PPERSIST is ON, the PK-12 uses the number set in PPERSIST and the time value set by
SLOTTIME to more randomly distribute the transmit wait time. This is more efficient than using the
DWAIT time.

PK-12 Packet Controller Operating Manual / 70

As a further attempt to improve performance, Eric Gustafson (N7CL) proposed giving priority to ac­knowledgment packets (acks); this protocol is controlled by ACKPRIOR. Check with the experienced
packet users in your area and find out if they are using priority acknowledge or have changed any other
parameters.

DAMA Support

Timewave has added DAMA (Demand Assigned Multiple Access) to the PK-12. DAMA allows for a
master/slave connection to reduce packet collisions. At times, a node’s receiver can hear too many signals
at once and remote users can get lost in the noise. A good example of this situation is when ships on the
open sea try, but can’t connect to communication satellites; the stations have a clear shot at the satellite,
yet can’t connect.

To solve this problem using existing equipment and still using only one frequency, DAMA has been
implemented to organize all node users’ communications. With DAMA, the master station identifies all
slave stations and polls each of them for information. Slave stations are ‘asked’ by the node if they have
any information to send. If a slave station does, the information is sent and the node ‘remembers’ that this
station sent information this time around. If a slave station does not send information, the master ‘remem­bers’ and skips this person next time around, coming back to them at a later time. Those stations replying
with information when polled are considered active. Stations that do not send information are considered
inactive. Active stations are given a higher priority than inactive stations and thus, more opportunity to
send information. As the node traffic increases, inactive users fall down through the priority list. Low pri­ority stations can become active (and have higher priority) at anytime by sending information when the
master station polls. Using DAMA can increase overall channel throughput by organizing stations based
on their state of activity. Stations sending data are given more chances to send data and stations not send­ing data are given less chancesave has added the UPlink command to the PK-12 for use with DAMA
communications. Information on this command can be found in the “You’re in Command” chapter of this
manual.

CHECK and RELINK

If a station connects to you and then turns its TNC off, you would probably not want to stay connected to
the station. The CHECK timer determines the amount of time your PK-12 will wait before testing the link
if no data has been exchanged.

RELINK sets what happens after the CHECK timer has expired. If RELINK is OFF, the PK-12 will
change to the disconnected state to terminate the link. If ON, the PK-12 will attempt to reconnect to the
distant station to reestablish the link.

Transparent Mode

Transparent mode allows any 8-bit binary character to be sent by your packet station. Usually, you must
use the Transparent mode to transfer binary and executable files to and from other stations.

You can either enter the Transparent mode by typing TRANS at the command prompt after you connect,
or by setting CONMODE to TRANS. Either way, once you enter the transparent mode, any character you
type will be sent automatically after the P ACTIME setting. This way any character can be sent by the PK-

12. Although we recommend using hard ware flow control in Transparent mode, software flow control is
available through the TRFLOW and TXFLOW commands.

To return to the Command mode after you’re finished with transparent mode, you must type the Com­mand character (CTRL-C) three times within the “guard time” set by CMDTIME (default: 1 second),
then wait an additional CMDTIME for the cmd: prompt to appear.

Sometimes you may need to send a file that contains some 8-bit data, but you don’t need all the features
of the Transparent mode. In this case, you may find tur ning the command 8BITCONV ON is all that is
needed.

Full-Duplex Operation

Most packet activity is conducted through half-duplex transcei v ers that transmit or receiv e , b ut not both at
once. In some systems where a separate transceiver and receiver is used (such as satellite operation), set
FULLDUP ON.

Morse ID in Packet

In most countries, packet is an accepted mode of identification so MID should be left OFF. (Your call
sign appears in the header information.) If a Morse ID is required where you reside, turn MID ON.

The QRA Feature

The PK-12 recognizes UI frames with a destination field of “QRA” and will respond by sending an ID
packet. This is helpful for others new to your area that are looking for other packet stations to talk to. To
disable this feature and remain anonymous, simply set UBIT 22 OFF.

If you want to see who’s available in your local area, simply set your UNPROTO path to QRA and send
a packet. Within 1 to 16 seconds, other stations should respond to your QRA request by sending an ID
packet of their own. This feature is compatible with TAPR’s QRA f eature introduced in their 1.1.8 firm­ware release.

PK-12 Packet Controller Operating Manual / 71

Packet Mail

Although standard TNCs allow incoming messages to be saved, there’s no way for the owner to leave a
message for someone who will connect at a future time. The ability to both send and receive messages
without the owner being present is accomplished by a mailbox.

There are many different packet mailbox systems in use. Some systems are large and require the use of a
dedicated computer. Other systems are small, like the personal MailDr op built into your PK-12.

Large systems are often called Packet Bulletin Board Systems (PBBS) since they serve as electr onic mes­sage centers for a local area. PBBS’s are a source of information as well as a gateway for messages that
can be sent to, and received from, other parts of the country or world. You will probably want to locate
the PBBS nearest you and connect to it from time to time.

Most mailbox systems are easy to use and, whether they are small or large, operate in much the same
way. Another nice feature of mailboxes and other automatic systems is that they usually have a Help file
or menu available to the caller by entering an “H” or “?” after a command line.

For more information on setting up and using your MailDrop, read Chapter 6 — MailDrop Operation.

PK-12 Packet Controller Operating Manual / 72

PK-12 Packet Controller Operating Manual / 73

6. MailDrop Operation

Overview

The PK-12’s MailDrop acts like a small post office—it uses a subset of the well-known W0RLI/
WA7MBL packet BBS commands to send and receive messages manually or automatically. Not only can
you originate and receive messages, but with 3RDPARTY ON, you can accept and relay messages left for
others.

The MailDrop also supports forwarding and reverse-forwarding of packet messages if properly coordi­nated with a local or “full service” BBS. This means that your station can receive messages from that
BBS, hold or send them on to their recipients, then return replies later after they’ve been answered. Hier­archical message addressing is now supported to simplify the routing of both national and international
traffic.

NOTE:

You needn’t have your computer on for your PK-12’s MailDrop to function, but y ou must leave your ra­dio on to allow other stations to access your MailDrop, or if you want to record the radio traffic the PK­12 hears.

MailDrop Memory

The number “n free” is the RAM space available for MailDrop messages. As your MailDrop fills with
messages, the RAM space will decrease until there isn’t any space left for messages or other activities.
When this happens, the MAIL light will blink on the front panel of the PK-12 to let you know that all the
RAM memory has been used up . If someone tries to connect to your station when this happens, they’ll
get:

*** (your call sign) busy - DISCONNECTED

. . . and will be automatically disconnected from your station.
Along these lines, while you’re logged on to your own MailDrop, if a station issues a connect request to

your PK-12 and it won’t let it connect—it will display the message:

*** (your call sign) busy

However, once you’re finished using your MailDrop—by entering B for Bye—your MailDrop will be
available to other stations.

When users connect to your MailDrop, they automatically connect to channel 9.

Setting Up Your MailDrop

Simply enter MAILDROP ON to enable MailDrop operation.
When operating in packet, your MailDrop can have its own call sign, which you enter in MYMAIL.

Common practice is to add an SSID after your call sign for this purpose, usually -1. If you don’t enter a

PK-12 Packet Controller Operating Manual / 74

call sign in MYMAIL, the MailDrop will use the call sign that you entered for MYCALL and all incom­ing connections will connect automatically to the MailDrop.

By the way , you have full control of your PK-12 while your MailDrop is on. You can connect to, and chat
with, other stations while someone is using your MailDrop, provided the user has connected to the call
you entered in MYMAIL.

It’s a good idea to enter a CTEXT message that says that if you don’t answer the user should reconnect to
your MailDrop through your MYMAIL call sign. An example would be:

cmd: CTEXT Hi! I’m not available right now, so please reconnect to WF7A-1 to leave a message in

my MailDrop. ‘73...Rich.

CText was
CText now Hi! I’m not available right now, so please reconnect to

WF7A-1 to leave a message in my MailDrop. ‘73...Rich.

Accessing and Commanding Your MailDrop

You must not be connected to any other stations when you access your own MailDrop. To check that
you’re “clear,” enter MDCHECK. If someone is connected to your PK-12, you’ll get the message: ?not
while connected. If you’re clear, you’ll see:

[AEA PK-12] 19712 free (B,E,K,L,R,S) >

The amount of free RAM available varies upon how much mail you already have stored in your mailbox
and whether or not you have the expanded mailbox option installed.

Console Commands

B, E, K, L, R, S are the MailDrop commands available to you as the “console” operator. The commands
mean:

B(ye) Log off from the MailDrop
E(dit) Edit a MailDrop message
K(ill) n Kill (delete) message number n
L(ist) List the message directory
R(ead) n Read a specific message n
S(end) call Send a message to a particular call sign

If you enter any command besides these six letters, you’ll get the error message:

*** What?

Monitoring Your MailDrop

NOTE:

Set MDMON ON to monitor another stations’ usage of your MailDrop. It will show you both sides of the
MailDrop QSO with your station. (Packet headers aren’t shown while a user is connected to your
MailDrop.) Conversely, turn MDMON OFF to cancel MailDrop monitoring. UBIT 13 allows MailDrop
connect and status messages to be disabled as well. (See UBIT 13 for more information.)

MailDrop Prompts and Operation

MTEXT is the MailDrop connect-message prompt sent to a user that’s connected to your MailDrop. The
default message is:

Welcome to my AEA PK-12 MailDrop.
Type H for help.

You can change it to your liking. For example:

cmd:MTEXT You’ve reached KG6ZL’s mailbox. If you need help, enter H.
MTExt was Welcome to my AEA PK-12 MailDrop.
Type H for help.
MTExt now You’ve reached KG6ZL’s mailbox. If you need help, type

H.>
cmd:

You must set MMSG ON for your MailDrop’s “welcome message” to be sent.
The MDPROMPT prompt message follows right after the Send command is entered. The default mes-

sage is:

PK-12 Packet Controller Operating Manual / 75

Subject:/Enter message, ^Z (CTRL-Z) or /EX to end

MDPROMPT is comprised of two different prompts that are sent to the connected station. The first
prompt is simply “Subject:”. When the connected station enters the subject of his message (max. 27 char­acters), the second prompt will appear:

Enter message, ^Z (CTRL-Z) or /EX to end

You can enter any text in MDPROMPT, up to a total length of 80 characters for both prompts; both parts
of the prompts must be separated by a forward slash (/) as shown—before the slash is your “Subject” line,
and after the slash is the “Enter message” line.

MailDrop Command Summary

When someone logs onto your MailDrop, the following commands will be available:

A, B, H, J, K, L, R, S, V, ?

Here’s what they mean:
A(bort) Aborts the reading of a message

B(ye) Log off from your MailDrop
H(elp) Help for the MailDrop commands
J(log) Sends the PK-12’s MHEARD list
K(ill) Kill or delete messages
L(ist) List the message directory
R(ead) n Read a specific message numbered “n”
S(end) n Send a message numbered “n”
V(ersion) Sends the PK-12’s sign-on message
? Help for the MailDrop commands [same as H(elp)]

A(bort) This is handy if the user decides not to continue reading a long message or a list. The

message, *** Done, followed by the MailDrop prompt will be sent after an “A” has

PK-12 Packet Controller Operating Manual / 76

been received. Although you can’t use the Abort command, you can use (CTRL-X) to
do the same thing.

B(ye) Logs you—or the calling station—off the MailDrop. As the console operator, you’ll see

the standard cmd: prompt; a calling station will be simply disconnected.

E(dit) # Available to the SYSOP only, Edit controls the status of the messages in your

MailDrop; you must access the MailDrop before typing this command. Here are all the
possible ways to use Edit:

E lists the following short help file:

E msg#
E msg# B/T/P
E msg# Y/N/F
E msg# >/</@ call sign

Examples:

E 12 Shows message #12’s information line.
E 23 > WF7A Sets WF7A as message #23’s destination.
E 35 < WF7A Sets WF7A as message #35’s source.
E 48 @ WF7A Sets WF7A as message #48’s destination BBS.
E 49 @ KG6ZL.MT.USA.NA

Sets KG6ZL as message #49’s destination BBS and adds the hierarchi­cal forwarding information, .MT.USA.N A , which directs the message to
the KG6ZL BBS located in the state of Montana (MT) in the United
States, North America (NA) continent.

E 58 @ Clears message #58’s destination BBS field.
E 60 P Sets message #60’s status to Private.
E 61 B Sets message #61’s status to Bulletin.
E 62 T Sets message #62’s status to Traffic.
E 63 Y Sets message #63’s status to Has-Been-Read.
E 64 N Sets message #64’s sta tus to Has-Not-Been-Read.
E 49 F Sets message #49’s status to Reverse-Forward.

The command E # F sets the message status to enable reverse-forwarding of a message
number. To cancel forwarding, set the status to either Y or N. Please read the section on
reverse-forwarding later in this chapter if you’re interested in this feature.

H(elp) This command, available to the user only, sends a list of all available MailDrop help

commands. A question mark will also cause the HELP file to be sent.

A(bort)

Stop Read or List
B(ye) Log off
H(elp) Display this message
J(log) Display stations heard

PK-12 Packet Controller Operating Manual / 77

K(ill) K n: Kill message number n

KM: Kill messages you have read

L(ist) L: List message titles

LM: List messages to you

R(ead) R n: Read message number n

RM : Read messages to you

S(end) S: Send a message to console operator

S n: Send a message to station n
V(ersion) Display TNC firmware version
? Same as H(elp)

J(log) Another command available only to the user, “J” will cause your MailDrop to send

your PK-12’s MHEARD list. (This command isn’t available to you as the console op­erator since you can simply enter MHEARD in the command mode to obtain the same
list.)

K(ill) n “K n” deletes message number “n” from the MailDrop. As console operator, you can

kill any message. A user can kill only messages addressed to (or from) that station. The
user may enter KM [(K)ill (M)ine] to delete all of the messages that have been previ­ously read.

L(ist) Shows you, the console operator, a list of all active messages on the MailDrop. The list

is preceded by the following column header:

Msg# Size To From @ BBS Date Time Title

All active messages are listed under this line with the most recent message first. DAY­TIME must be set for the Date and Time information to appear. If DAYTIME isn’t set,
periods will appear under the Date and Time fields.

When a user enters the List command, the MailDrop lists only the messages that par­ticular user is allowed to read, including messages addressed to ALL and QST; mes­sages to other users aren’t displayed. The MailDrop also accepts the LM (List Mine)
command from the user. This shows messages addressed only to that particular user,
not messages addressed as ALL, QST, or Bulletins.

R(ead) n This command displays the header and text of message number “n”. Messages are read

by number, not call sign. As console operator, you can read all messages. A user may
read only messages addressed to his call sign, or to ALL, QST, or Bulletins.

The MailDrop accepts the RM (Read Mine) command from users. This command acts
only on messages addressed to the user, not messages addressed to ALL or QST. RM
displays only messages that haven’t been read.

S(end) The S (call sign) command notifies the MailDrop that either you, as console operator,

or the user wants to send a message.
With 3RDPARTY ON, the connected station can leave a message for another station or

to you. However, if you have 3RDPARTY OFF, then the calling station will see:

PK-12 Packet Controller Operating Manual / 78

*** No 3rd party traffic
[AEA PK-12] 18396 free (A,B,H,J,K,L,R,S,V,?) >

See the next section, Sending Mail, for information on how to send mail.

V(ersion) This user command causes the PK-12 to send the sign-on message and its firmware

date.

? (H)elp Another user-only command, “?” sends the user the same list of MailDrop commands

as the “H” command does.

Sending Mail

From the Console Operator

To send mail, you have to log onto your MailDrop by entering MDC (MDCHECK). When you do, you’ll
see the following:

cmd:MDC
[AEA PK-12] 19712 free (B,E,K,L,R,S) >

Enter S (call) of the station you want to send mail to. If you want to send mail to KB6IUX, enter:

S KB6IUX
Subject:

Type in a subject line (max. 27 character s), then press (RETURN). You’ll then be prompted with:

Enter message, ^Z (CTRL-Z) or /EX to end

Go ahead and enter your message; you can either have the PK-12 “wrap” your text as you reach the end
of the line or press (RETURN) to go to the next line. You won’t have text that breaks in the middle of a
word if you use a (RETURN) to start a new line.

When you’ve finished writing your message, press the (RETURN) key and enter either a
(CTRL-Z)+(RE-TURN) , or /EX on a new line to end the message. The MailDrop prompt should then

n

appear, saying: Message stored as #
After ending the message, if you or the calling party see the message *** No free memory, this

means that the message was too large for the available MailDrop memory and wasn’ t recorded. If this oc­curs, you must delete stored mail or re-enter a shortened message to fit into the available memory space.

When logged on from your k eyboard, if you use the “S” command without a call sign, you’ll see the error
message
message will to go to you, the console operator.

*** Need call sign

. However, when calling stations use “S” without a call sign, the

. It will be then ready to accept your next command.

NOTE:

As soon as a calling station uses “S” to send you (the console operator) a message, the STA light starts
blinking to let you know that a message has been left for you. When you log on to your MailDrop, the
STA light will stop blinking.

Sending Other Types of Messages

Each message in the PK-12’s MailDrop has a flag to show whether it’s designated as Private, Traffic or a
Bulletin. A “P,” “T,” or “B” after the message number shows the status of every message. A user sets this
with the SP, ST, and SB forms of the Send command. You can change or set the status of these messages
using the Edit (E) command described above. If only “S” is used as the Send command, the MailDrop
will assign the message a Private (P) status.

The MailDrop also accepts Send commands in the form SP console operator < W1AW. The call sign af-
ter the “<” goes into the “From” field of the message header.

For example, your MailDrop accepts the following additional information in a Send command:

S KG6ZL @ KB6IUX.CA.USA.NA < WF7A

This means you’re going to send a message to KG6ZL at the KB6IUX BBS in California, USA, North
America, and that the message is from WF7A.

The MailDrop also supports BIDs (Bulletin IDs); this support is required for reverse-forwarding. The
BID begins with a “$” character and is sent and received in the Send command line:

S KB6IUX @ KG6ZL < WF7A $345_WO6P

This means you’re sending a message to KB6IUX, who uses the KG6ZL BBS; the message is from
WF7A and it’s bulletin #345 from WO6P.

PK-12 Packet Controller Operating Manual / 79

With the MailDrop, you can also use just the “$” all by itself as shown in the two examples below:

S KB6IUX @ KG6ZL < WF7A $

S ALL $

With the “$” sign, the MailDrop will assign its own BID to these messages.

From the User’s Point of View

Assume that your MailDrop (MYMAIL) call is KB6IUX-1 and WO6P wants to connect to it. During his
session with your MailDrop, he wants to list your MailDrop’s messages, see if there’s a message from
you, read it if it exists, delete it after he’s done reading it, send a return message to you, then finally dis­connect from your MailDrop.

From his cmd: prompt, he’ll type the usual connect request. He’ll see this:

cmd:C KB6IUX-1
*** CONNECTED to KB6IUX-1
You have mail.
[AEA PK-12] 16508 free (A,B,H,J,K,L,R,S,V,?) >

The “You have mail” message informs WO6P that there’s mail waiting for him. He types “L” to list all
the current messages in the MailDrop.

[AEA PK-12] 16508 free (A,B,H,J,K,L,R,S,V,?) >

L

Msg# Size To From @ BBS Date Time Title
6 PN184 WO6P KB6IUX WF7A 24-Nov-94 20:15 Gobble!
5 BY287 ALL KB6IUX 21-Nov-94 18:42 Question
4 BY178 QST KB6IUX 19-Nov-94 17:30 Mailbox
1 BY 56 ALL KB6IUX 23-Nov-94 10:22 APLINK
[AEA PK-12] 16508 free (A,B,H,J,K,L,R,S,V,?) >

...or

PK-12 Packet Controller Operating Manual / 80

He sees the list of messages and the one in particular that’s addressed to him. He types “R 6” to (R)ead
MSG# 6.

[AEA PK-12] 16508 free (A,B,H,J,K,L,R,S,V,?) >

R 6

Msg# Size To From @ BBS Date Time Title
6 PN184 WO6P KB6IUX WF7A 24-Nov-94 20:15 Gobble!
Happy Thanksgiving, guy! Knowing that _you’re_ cooking the big meal for your
family tonight, should I rush a case of Pepto-Bismol over to you now?
73, Rich.
[AEA PK-12] 16508 free (A,B,H

He’s read your message and now he wants to (K)ill it. He types:

[AEA PK-12] 16508 free (A,B,H,J,K,L,R,S,V,?) >

K 6

*** Done.
[AEA PK-12] 16580 free (A,B,H,J,K,L,R,S,V,?) >

He’s killed the message and wants to send a re ply back to KB6IUX (you). We’ll continue from where he
left off.

As a habit, look to see if enough memory remains for the length of message you intend to send.

,J,K,L,R,S,V,?) >

NOTE:

[AEA PK-12] 16580 free (A,B,H,J,K,L,R,S,V,?) >

S

Without a call sign, the MailDrop will address the message to the MYMAIL call sign unless your MY­MAIL call sign wasn’t entered—then it would go to your MYCALL call sign. Messages sent with the
“S” command are sent (P)rivate unless they are sent to “ALL” or “QST.”

Subject:

Hey, wise guy...

Enter message, ^Z (CTRL-Z) or /EX to end

...will you be the only turkey at your table?
See you later, and all the best to you and Audrey.

(CTRL-Z)

Message stored as #7
[AEA PK-12] 16427 free (A,B,H,J,K,L,R,S,V,?) >

B

*** DISCONNECTED: KB6IUX-1

If the message was ended with a “/EX”, the last line in the letter will have “/EX” automatically inserted.
To avoid having /EX inserted, use (CTRL-Z) to end messages.

Message Numbers

Every message that’ s sent to the MailDrop is gi v en a message number. Message numbers start at 1 and in­crement by one to 999; after 999, the next message will start at “1” again. If you need or want to, you can
reset the message counter using the LASTMSG command—just enter LASTMSG 0. The next message
entered after this command will be numbered, “1.” If you enter a LASTMSG number other than zero, the
next message will be assigned the number immediately following the value you entered. For example, if
you enter: LASTMSG 100, the next message entered into your MailDrop will be number 101.

NOTE:

Forwarding and Reverse-Forwarding

Forwarding allows your local full-service Bulletin Board System (BBS) to automatically connect to your
MailDrop to leave mail. Likewise, reverse-forwarding allows your BBS to connect to your MailDrop to
retrieve mail left at your station. These operations are done automatically, if the correct commands are en­abled in your PK-12 and the mail in your MailDrop is assigned the correct coding.

Forwarding and reverse-forwarding (or auto-forwarding) can be an advantage in a metropolitan area. The
BBS can be set to connect to your MailDrop at times when local traffic is low, such as late at night or
very early in the morning when packet traffic is light.

Auto-forwarding requires the cooperation of both you and your BBS “SYSOP,” because not all large
BBSs will forward mail to individual users. Some packet frequencies are so busy with BBSs forwarding
mail to other BBSs that they can’t forward mail to individuals. Contact the BBS SYSOP to determine the
guidelines in your area.

Settings for Auto-Forwarding

For auto-forwarding to work:

1. Enter your MYCALL (and MYMAIL call sign if you want to use a separate call sign for your
MailDrop).

2. Make arrangements with your local BBS operator to auto-forward mail to your MailDrop. Make
sure you let him know the MailDrop’s call sign.

3. Enter the call sign of the BBS in HOMEBBS.

4. Set MONITOR to 0 so the PK-12’s buffer will record only messages addressed to—or passed
through— it and won’t fill up with idle radio traffic.

5. Leave your PK-12 and radio on and set to the appropriate frequency so that the BBS can connect
to your MailDrop. If your packet station isn’t on when the BBS tries to connect, mail won’t be for­warded and its SYSOP will mutter unprintable things.

PK-12 Packet Controller Operating Manual / 81

Entering a Message for Reverse Forwarding

With reverse-forwarding, the local BBS can retrieve mail from your MailDrop—entered by you or left by
other stations—automatically and send it on the way to its final destination. To create a message that will
be reverse-forwarded:

1. Enter MDCHECK to access your MailDrop from your computer.

2. After entering the Send command and the recipient’s call sign, use the “@” field to set the destina­tion BBS where the recipient of the message will pick up his mail. For example, if you want to send
a message to KB6IUX, who you know uses KG6ZL’s BBS, enter the following:

S KB6IUX @ KG6ZL.CA.USA.NOAM

The call following the “@” sign doesn’t need to be the same as the HOMEBBS call sign.

The “.CA.USA.NOAM” is optional hierarchical forwarding information that, in this case, desig­nates that KG6ZL is located in California in North America.

3. Enter the Subject and text of the message as you normally would. Don’t forget to end your message
with a (CTRL-Z) or “/EX”.

4. After you’re finished, log off from your MailDrop by entering B.

To readdress a letter already in your MailDrop for reverse-forwarding:s

NOTE:

PK-12 Packet Controller Operating Manual / 82

1. Use the Edit command to set the forwarding flag for each message that will be reverse-forwarded
to the call sign in HOMEBBS. For example, to mark message number 53 for reverse-forwarding,
type:

E 53 F

2. After you’re finished, log off from your MailDrop using B.

If you want a message to be deleted from your MailDrop after it has been reverse-forwarded, leave
KILONFWD ON; if you want to keep the message after it has been forwarded, leave KILONFWD OFF.

With KILONFWD OFF, after the message has been forwarded the message’s flag will change from “F”
to “Y” to show that it has been read and sent.

NOTE:

7. GPS Operation

Overview

This chapter describes how to configure and connect your TNC for GPS operation.

Why do GPS in the PK-12?

All Timewave TNCs can run with Automatic Packet Reporting System (APRS™) software. The PK-12,
however, has special firmware which makes Stand Alone Tracking and Ultimeter II® compatibility pos­sible. Timewave also offers an APRS Adapter Cable for the PK-12 which makes Hardware Single Port
Mode (HSP) operation possible. The reason we chose to put special firmware in the PK-12 and develop
the APRS Adapter Cable for the PK-12 is because this TNC is perfect for going mobile; which is what
Global Positioning Systems are all about.

The PK-12 contains special GPS features not found in other packet Terminal Node Controllers. The PK­12 can detect whether or not a GPS receiver is connected with the GPSAuto command, it then chooses
the appropriate GPSMode of operation. If a GPS receiver is detected upon power-up, the PK-12 auto­matically sends a GPS initialization string. The PK-12 can be remotely polled by addressing a packet to
its GPOLLCall, or by the polling features in APRS. The PK-12’s GPS commands can be remotely pro­grammed using the GREMprog command which is very convenient in Stand Alone Tracking applica­tions—the unit never needs to be taken out of the vehicle to change GPS settings. GPS receivers can be
remotely programmed via the PK-12. The PK-12’s internal time and date can be set from the information
obtained from the GPS receiver. There are provisions for an external input to cause the sending of NMEA
strings, such as from a radio control head button. The PK-12 can even operate packet and GPS at the
same time using the commercial mode. See You’re in Command chaper, G section for GPS commands.

PK-12 Packet Controller Operating Manual / 83

What is APRS?

Timewave has included a copy of APRS in
your PK-12 packaging so you can experi­ment with it. Automatic Packet Reporting
System (APRS™) is a copyrighted soft­ware program developed by Bob Bruninga
(WB4APR), which is distributed as
shareware for real-time Packet communica­tions. The software keeps lists of stations
heard and displays the locations of stations
visually on a computerized map like the one
in Figure 1. The maps can be scaled from .5
to 2000 miles. Few of the maps are com­plete, however there are tracking features built into APRS which allow you to create maps just by driving
down the streets of your town. Amateur operators all over the country are creating maps which can be
downloaded from on-line systems for use by all. Stations can appear on the maps and each station may be
given a symbol such as a house, car, or boat. The real benefit of using APRS software is in mobile track­ing applications. Vehicles and people can be tracked and mapped using APRS. APRS also includes the
ability to send short messages and bulletins. Using Ultimeter II weather information can also be shown on
the computerized maps.

FIGURE 1: APRS computerized map

84 / PK-12 Packet Controller Operating Manual

Hardware Configurations

There are four different hardware configurations you can use when operating within an APRS system,
each for a different purpose:

1. A computer running APRS, a GPS receiver, a PK-12, an APRS Adapter Cable (optional), and a radio:

This complete configuration allows you to track all users on the system in your area (including yourself),
and send/receive messages and bulletins. Using Timewave’s APRS Adapter Cable, you can connect a
GPS receiver and a PK-12 to a single COM port on a computer running APRS, see Figure 2. Without
Timewave’s APRS Adapter Cable, the PK-12 and GPS receiver would need to be connected to separate
COM ports. Having two COM ports free on most computers is a luxury most us don’t have with all the
Windows related equipment such as mice and other serial peripherals. Mobile laptop computer users need
the APRS Adapter Cable because most only have one COM port.

Running

Running

APRS

APRS

FIGURE 2: APRS HSP mode where APRS controls the cable switching between the TNC and GPS receiver

2. A computer running APRS software, any Timewave TNC, and a radio (No GPS receiver):

This configuration lets you track all users on the system with your location being entered manually. This
also lets you send and receive messages within APRS. All Timewave TNCs can be part of a system such
as this. This configuration allows anyone with any Timewave TNC who is running APRS software in
their computer to take part in this GPS technology. You don’t need a GPS receiver to pull down location
information from the satellites because you enter your position manually on the APRS computerized
map, which in most cases is fine because you are at your house which doesn’t (shouldn’t) move. The only
time you really need a GPS receiver is when you are operating packet while mobile because manually
updating your position while mobile isn’t practical—you need the GPS receiver to pull in those satellite
location signals and update your position as you move.

3. A PK-12, a GPS receiver, and a radio (No PC):

This trio allows you to transmit your location automatically to others in an APRS system without having
a computer in the vehicle. This is known as a Stand Alone Tracking Device because others can track your
motion without you having to run APRS or even have a computer. The firmware in the PK-12 allows the
TNC to parse the incoming location information from the GPS receiver (without the use of a computer
running APRS whic h usually does the parsing) and then beacon the inf ormation over the ham bands.

PK-12 Packet Controller Operating Manual / 85

Because the PK-12 can work both as a stand alone tracking device and as a connected APRS component,
this TNC can be of aid in natural disaster situations, during public service events, and search and rescue
missions, among other things.

For example, in a marathon, a pace car, ambulances, and other support vehicles could each have a PK-12
acting as a Stand Alone Tracking Device. A coordinator can be in a centralized location using a PK-12,
radio, and an APRS Adapter Cable (optional) to connect with a computer running APRS software to visu­ally track the vehicles. When an emergency arises, such as an injured runner, the coordinator can see
which ambulance is closest to the scene and dispatch it appropriately through voice communications.

Further, if all vehicles in the previous example we re equipped with a PC running APRS, a PK-12, a GPS
receiver, a radio, and an APRS Adapter Cable, the coordinator could not only see where the vehicles were

- he could dispatch them directly through the APRS system. T he drivers of the vehicles would receive
short messages from the coordinator such as, “Runner down, 4th and Main. Vehicle 2 respond.” These
short messages appear on the individual driver’s computer screen much like typical Packet messages. The
messages can also be accompanied by computer ‘beeps’ to alert the driver to an incoming message.
APRS includes a bulletin feature where all vehicles could receive messages simultaneously such as,
“Take lunch.”

4. PK-12, ULTIMETER II, and a radio (No PC):

This configuration requires an ULTIMETER II home weather station, see Figure 3 below. (Information
on ULTIMETER II weather station packages can be obtained by calling 1-800-USA-PEET.) In case you
are not familiar with ULTIMETER II, it is a weather station package including a control panel into which
a thermometer, wind gauge, and an optional rain gaug e are connected. If you like, you can monitor the
temperature of any room in your home, keep track of temperatures in a greenhouse or outbuilding, or set
alarm limits on a freezer or other appliance.

FIGURE 3: Illustrates components of a stand alone packet weather station

The PK-12 can be connected to the ULTIMETER II weather station, interpret the weather data, and
transmit the weather and location information in packet so other APRS users can see your location and
the weather at your location. The remote polling features of the PK-12 make it easy to set up a wea ther
station in a remote location and receive the remote weather data via APRS at your house, office, or wher­ever. While at work, you can keep track of the weather situation at your home (inside or outside tempera­tures—whichever you prefer). Farmers can keep apprised of rain,wind, and temperature at a remote field
site. In addition, several weather stations set up in your region can provide you with a comprehensive
weather picture of your area—available to you and all other users at anytime. The PK-12, ULTIMETER

86 / PK-12 Packet Controller Operating Manual

II, and APRS add a whole new dimension to packet radio—we hope you experiment with this new appli­cation. Set-up procedures for an Ultimeter II weather station are discussed later in this chapter.

Installing APRS

Timewave has included a disk containing PC PakRatt Lite and APRS. For your convenience, we have in­cluded an installation utility on the disk called INSTAPRS.BAT.

To install APRS on your hard drive perform the following steps:

1.Type MD APRS, then press ENTER.

2.Type CD APRS, then press ENTER.

3.Type A:INSTAPRS C:\APRS, then press ENTER. (where A: designates the floppy drive with
your master diskette, and C:\APRS is the full drive and path name of the destinations hard disk
drive and subdirectory.)

Getting started:

a. Type APRS66 at the command prompt.
b. Give your callsign and other info as prompted.
c. Move the cursor to your exact QTH using the arrow keys and PgDn keys.
d. Press I (Input), then M (My-position), and answer the questions.

At this point, APRS will begin beaconing your loca tion and displaying other people’s locations on the
screen.

Ask around your local amateur community to find a frequency operating APRS in your area. Also, you
might ask where to find additional, detailed maps of your area other people have created.

In the C:\APRS\README directory, there are a vast number of text files that explain how APRS works.
Registration information is also contained in the readme files, information you will need if you want to
set up an APRS weather station or operate Hardware Single Port Mode. T i m ewave does not provide tech­nical support for APRS, however, we do provide support for PC PakRatt Lite.

Setting Up the PK-12 for GPS Operation

Set up procedures for the PK-12 are described below for three Packet/GPS configur ations: Stand Alone
Tracking, APRS Hardware Single Port mode, and APRS Dual Port Mode. APRS software automatically
sets the parameters for your TNC, except when the PK-12 is used as a Stand Alone Tracking Device (be­cause APRS isn’t connected).

Stand Alone Tracking Device Set-up:

To set up the PK-12 for Stand Alone Tr acking, follow these steps:

1. Connect your TNC to your computer and get it up and running following the directions in Chapter

2.

2. Type MY <your call sign>-9, then press ENTER. For example, if your call sign is WA7GCI you
would enter MY WA7GCI-9, then press ENTER. The -9 will cause others to see you as a car on
the APRS map.

3. Program the UNPROTO command to: UN APRS via RELAY, then press ENTER. This programs
your unproto path to APRS via RELAY.

4. Type GLOCtx 6, then press ENTER. This causes the TNC to transmit its GPS location every 60
seconds. The seconds can range from 0 (disabled) to 255 in ten second increments.

PK-12 Packet Controller Operating Manual / 87

5. Now you need to program the commands, GNMEA1 and/or GNMEA2, for the desired NMEA
(GPS) sentences for the PK-12 to parse. Not all GPS receivers can send all NMEA sentences. So,
the instructions you see below depend on the ability of your GPS receiver to send desired NMEA
strings. In any case, the PK-12 can handle any NMEA strings your GPS or Loran receiver can pro­duce.

To program GNMEA1, type GNMEA1 $GPGLL and press ENTER. This command allows the
PK-12 to parse the Position-Only NMEA string coming from the GPS receiver and place the string
in the transmit buffer. The result of $GPGLL is that you will be able receive from the GPS receiver
Position-Only information and transmit it over the ham bands. (Any NMEA string your GPS re­ceiver can produce can be entered in this command line.)

The neat thing about the PK-12 is that you can choose not one, but two NMEA strings to parse.
You can, for instance, use Position-Only and Course/Speed. To program the second NMEA string
for the PK-12, type GNMEA2 $GPVTG and press ENTER. This sentence alone allows you to
transmit course and speed. When coupled with the GNMEA1, your position, course, and speed will
be transmitted together. (Again, you can use any NMEA string your GPS receiver can produce in
this command line.)

Note: The NMEA sentence $GPRMC is the recommended sentence for tracking moving objects as
it contains time, latitude, longitude, course, and speed information.

6. Now type GPSAuto ON, then press ENTER. This will cause the PK-12 to look for GPS data
(coming from an attached GPS receiver) the next time it is powered on, and if it sees GPS data the
PK-12 will automatically switch to GPSMode 1.

7. Now you need to program the PK-12’s terminal baud rate to match that of the GPS receiver, which
is normally 4800 baud. To program the PK-12 terminal baud rate, type TBAUD 4800, then press
ENTER.

8. Now turn your PK-12 off and disconnect your TNC from the computer. Take the PK-12 to your ve­hicle, connect the TNC to the GPS receiver and the radio, plug it in, power it up and you’re in busi­ness. Note: Before powering up the PK-12, be sure the GPS receiver is powered up and outputting
its NMEA sentences.

Connecting the GPS receiver to the PK-12

Figure 4 below illustrates the pin assignments for connecting a GPS receiver to the PK-12. The same pin
assignments can be used to connect to a Peet Bros. ULTIMETER II® weather station.

Momentary closure to ground causes TNC to immediately parse and transmit its location (pin 4)
This option ( no t e ssential for operation) gives you th e ab il ity to c o nfi gu re a radi o head button
to transmit position information at a ny tim e.

Connect the GPS receiver or ULTIMETER II NMEA output to pin 2

Connect Ground to pin 1

P O W E R

+ 1 3 V D C

C O M P U T E R

(R S - 2 3 2 )

T X

L E V E L

Rear View of the PK-12

FIGURE 4: Pin assignments for connecting the PK-12 to a GPS receiver or to an Ultimeter II weather station

R A D I O

G N D

1

T X

4

R X

2

3

P T T

5

S Q

88 / PK-12 Packet Controller Operating Manual

9. When done using the PK-12 as a Stand Alone Tracking Device, connect your TNC to the computer
again, verify that your terminal baud rate is at 4800 baud, 8 bits, no parity, one stop bit. A few sec­onds after powering up, the PK-12 should display its sign-on message and command prompt.

APRS Hardware Single Port Mode (HSP) Set-Up: Requires a registered version of APRS

APRS version 4.03 and higher includes a routine that controls the switching of the Single Port Mode be­tween the TNC and any GPS receiver using the handshaking lines of the COM port. HSP allows you to
operate APRS on a computer with limited COM ports, such as a laptop which usually has only one COM
port, or your PC which uses one of the two COM ports dedicated to a mouse. This is the only configura­tion which uses the APRS adapter cable. You will need to have a registered copy of APRS in able to acti­vate the GPS input. Registration information is contained in the APRS readme files.

Follow these steps to connect the APRS Adapter Cable to your equipment:

1. Look at the APRS adapter cable. It looks like this:

Notice the words on the outside of the rectangle; they say TNC, Computer, and GPS. This is how
the Cable should be connected.

2. Connect the APRS Adapter Cable to the serial port on the TNC. The male side of the Adapter
Cable, labeled TNC, should be connected to the female serial port on the PK-12.

3. Connect an RS-232 (not included) to a free COM port on your computer. Connect the other end of
this cable to the RS-232 port marked “Computer” on the APRS Adapter Cable. (The female side of
the Adapter Cable, labeled ‘computer’, should be connected to a cable going to the computer.)

4. The cable that comes out the side of the APRS Adapter, labeled “GPS”, connects to the NMEA­0183 port on your GPS receiver.

The cable is now correctly connected to your equipment.

To set up the PK-12 for HSP operation, follow these steps:

1. Connect your TNC to your computer, and to your GPS receiver using the Timewave APRS
Adapter Cable following the steps noted previously. Get the computer running APRS software and
the TNC running. Leave the GPS receiver off until you are ready to receive the NMEA string.

2. Press ALT-S to bring up the setup menu.

3. Now press G for GPS.

4. Press H for HSP.

5. Now press ALT-S to save.

6. Enter S for SAVE.

7. Now follow the prompt from APRS to validate your APRS registration and save the mode changes.

8. Turn your GPS receiver on, and you are ready for APRS HSP operation.

9. When finished using the PK-12 for APRS HSP operation, simply quit APRS. APRS may ask you
for some information before quitting. Answer the questions and when done, your PK-12 will be
ready for non-GPS activities.

APRS Dual Port Mode Set-up:

To set up APRS for dual mode operation, follow these steps:

1. Connect your PK-12 to one of the COM ports on your computer. Get the TNC up and running fol­lowing the directions in Chapter 2 of this manual.

2. Connect your GPS receiver to the other COM port on your computer. (You will need to build your
own cable for this connection. Since there are many types of GPS receivers, all with different con­nections, we can’t provide you with schematics on how to build this cable.)

3. Get the APRS software program running. APRS will ask you some questions, simply answer the
questions and your TNC and APRS will be ready for dual port mode operation.

Building your own APRS adapter cable

The APRS adapter cable wo rks as follows:
The adapter allows for Hardware Single Port mode (HSP) operation, so you only need one computer

COM port for both your GPS receiver and PK-12. The adapter normally has the TNC switc hed to the
computer until APRS decides it’s time to send its location report. When it’s time to send position informa­tion, the computer running APRS asserts flow control to the TNC to prevent it from sending any more
data. The flow control line is also used to switch the adapter to the GPS receiver. Once the GPS string is
received, the computer running APRS releases flow control, switc hing back to the TNC.

PK-12 Packet Controller Operating Manual / 89

A pre-made and tested cable can be purchased from Timewave for $35.00, including shipping and han­dling, by calling [phone]. For best pricing, see your favorite amateur radio dealer.

An APRS adapter cable can be made from the following components with the schematic shown on the
next page.

Item Description Qty Radio Shack Part #

1. PCB 1

2. 1K resistor 1 271-023

3. 10K resistor 2 271-034

4. IN4148 diode 2 276-1122

5. 2N3904 NPN transistor 2 276-2016

6. DB-25 male connector 1

7. DB-25 female connector 1

8. DB-25 hood 1

9. Screws for hood 1

10. Saddle washers 1

11. Hex nuts 1

12. 6ft shielded cable 1

Connecting the APRS adapter cable

Once you’ve made your adapter cable, connect as described on page 87.

90 / PK-12 Packet Controller Operating Manual

Schematic Diagram for the APRS Adapter Cable

PK-12/ULTIMETER II® Stand Alone Weather Station Set Up

Connect the ULTIMETER II to the PK-12 following the illustrations of Figure 3, Figure 4, and Figure 5.
Once the connections are made, follow the directions below to configure the TNC.

1. Connect your TNC to your computer and get it running following the directions in Chapter 2.

2. Type MY <your call sign>, then press ENTER. For example, if your callsign is WA7GCI, you

would enter MY WA7GCI, then press ENTER.

3. Type UN APRS via RELAY, then press ENTER. This programs your UNPROTO path to APRS

via RELAY.

4. Type GLOCtx 60, then press ENTER. This causes the PK-12 to transmit the weather information

every 10 minutes. The seconds can range from 0 (disabled) to 255 in ten second increments.

5. Now you need to program your Btext with the day of the month, time, and your latitude and longi­tude. For example: if your exact location is 47°49.14’N, 122°15.72’W and the time and date is 9:11
AM June 23 1995, you would enter BT @230911/4749.14N/12215.72W_Lynnwood weather
station, then press ENTER.

6. Now type Beacon E 60, then press ENTER. This will cause your PK-12 to transmit its beacon text
every five minutes. APRS must see the beacon text containing the position information and a
weather symbol character before it will display your weather information.

7. Now you need to program the GNMEA1 sentence to match the output of the ULTIMETER II.
Type GNMEA1 #, then press ENTER. This will cause the PK-12 to begin parsing the
ULTIMETER II data starting with the # digit. ( Note some ULTIMETER IIs start their string with

a # digit and some start their strings with a * digit. This value may have to be changed to a * if it
does not work upon installation.)

PK-12 Packet Controller Operating Manual / 91

8. Type TBAUD 2400, then press ENTER. This sets the PK-12 serial baud rate to match the output

of the ULTIMETER II.

9. Now type RESTART, then press ENTER. This will cause the terminal baud rate to change to 2400

baud matching the ULTIMETER II. Change your terminal baud rate to 2400 baud to match that of
the PK-12.

10. Now type GPSMode 2, then press ENTER. Now press ENTER again to enter the stand-alone

weather station mode. Now disconnect the serial cable and connect the ULTIMETER II, and you
are ready to transmit weather information in an APRS system.

FIGURE 5: Ultimeter II junction box pin assignments

Wireless Data/Location Tracking Applications

Timew ave offers the Commercial GPS Adapter Ca ble for Wireless Data/Location Tracking Applications.
This cable allows the GPS receiver and computer to share the TNC’s serial interface. The PK-12 itself is
designed to parse the incoming GPS information, that is, the TNC does the switching between the GPS
receiver and the computer as illustrated in Figure 6. This allows the TNC to perform normal packet radio
communications and also transmit position information in the background. Users who have a computer
may transfer files and communicate with each other while also transceiving global positioning informa­tion. Users without computers can use the TNC as a Stand Alone Tracker to transmit position information
to a base station that does have a computer keeping track of the location of many mobile vehicles.

The key to this set-up is having computer software that can handle both mapping and data transceiving
tasks. Software of this kind is most often custom written for a specific business which is why we called
the cable needed for wireless data/location tracking applications the Commercial GPS Adapter Cable.

Configuring the TNC

There is one hardware configuration possible when using the GPS Ada pter Cable and that is for use with
wireless data/location tracking applications. The GPS Adapter Cable makes it possible to transfer packet
data while beaconing current location information in the background. If a computer is not going to be
used, the Adapter Cable is not needed. If the Commercial GPS Adapter Cable is not used, the GPS re­ceiver can be connected directly to the PK-12’s serial port and the TNC should be configured for Stand
Alone Tracking, discussed previously.

92 / PK-12 Packet Controller Operating Manual

FIGURE 6: In this configuration, data

and

GPS data can be sent and received.

Wireless Data/Location Tracking setup:

To set up the TNC for this application, follow these steps:

1. Connect the TNC to a computer and get it up and running, following the directions in the Getting
Started section of the TNC’s manual.

2. Type MY <your callsign>, then press ENTER. For example, if your call sign is WA7GCI, you
would enter MY WA7GCI, then press ENTER.

3. Set the TBAUD to 4800, matching the GPS baud rate.

4. Type GLOCtx 6, then press ENTER. This causes the TNC to transmit its GPS location every 60
seconds. The seconds can range from 0 (disabled) to 255 in ten second increments.

5. Now you need to program the commands, GNMEA1 and/or GNMEA2, for the desired NMEA
(GPS) sentences the TNC will parse. Not all GPS receivers can send all NMEA sentences. So, the
instructions you see below depend on the ability of your GPS receiver to send the desired NMEA
strings. In any case, the Timewave TNC can handle any NMEA strings your GPS receiver can pro­duce.

To program GNMEA1, type GNMEA1 $GPGLL and press ENTER. This command allows the
TNC to parse the Position-Only NMEA string coming from the GPS receiver and place the string
in the transmit buffer. The result of $GPGLL is that you will be able to receive from the GPS re­ceiver Position-Only information and transmit it over the radio. (Any NMEA string your GPS re­ceiver can produce can be entered in this command line.)

The nice thing about the Timewave TNCs is that you can choose not one, but two NMEA strings
to parse. You can, for instance, use Position-Only and Course/Speed. To program the second
NMEA string for the TNC, type GNMEA2 $GPVTG and press ENTER. This sentence alone al­lows you to transmit course and speed. When coupled with the GNMEA1, your position, course,
and speed will be transmitted together. (Again, you can use any NMEA string your GPS receiver
can produce in this command line.)

The NMEA sentence $GPRMC is the recommended sentence for tracking moving objects as it contains
time, latitude, longitude, course, and speed information.

NOTE: