Wulfsberg Electronics Division NPX136D User Manual

PRELIMINARY

NPX136D-070 VHF P25 Panel Mount Transceiver

OPERATOR’S MANUAL

REV 0.01 April 5, 2004

Northern Airborne Technology Ltd.

#14-1925 Kirschner Road

Kelowna, BC, Canada.

V1Y 4N7

Telephone [phone]

Facsimile [phone]

Copyright 2004 by Northern Airborne Technology Ltd.

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Table of Contents

Section Title Page

1.1 Introduction 3

1.2 Purpose of Equipment 3

1.3 Features 3

1.4 Operation 4

1.4.1 General 4

1.4.2 Power On 4

1.4.3 Controls 5

1.4.4 Normal Oper ating Mode 8

1.4.5 Menu Mode 10

1.4.6 Direct Function Operations 19

1.4.7 Scanning 19

1.5 Specifications 20

1.5.1 Radio Specifications 20

1.5.2 Main Receiver 21

1.5.3 Guard Receiver 21

1.5.4 Transmitter 21

1.5.5 Physical Specifications 22

1.5.6 Environmental Specifications 23

1.6 Unit Nomenclature 23

1.6.1 Options 23

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1.1 Introduction

This manual contains description and operation information on the NPX136D-070 Panel
Mount P25 VHF Transceiver, serial number 1001 and subsequent.

The NPX136D incorporates NAT’s proven user-friendly operating system with on -line
help, making it easy to program and use. The small size makes this radio ideal for
airframes where size and weight are a factor.

1.2 Purpose of Equipment

The NPX136D panel mount P25 VHF transceiver is a stand-alone radio designed for
the single mission user. It provides all the features needed to satisfy communications
within the VHF high band.

1.3 Features

The NPX136D covers a frequency range of 136.0000 to 173.9975 MHz in 2.5/6.25 kHz
increments. Each of the 256 available channels can operate in one of three modes:
wide band analog, narrow band analog or digital P25 Phase I.

A SCAN function allows scanning of selected channels. Transmit power of either 1 watt
or 10 watts is selectable from the front panel. Simplex and semi-duplex operations are
available. A guard receiver is standard with the -070 model.

Conveniently located beside the display are separate main volume, guard volume and
transmit select switches. Easily identified along the bottom of the front panel are
squelch test, channel up/down and display controls. The aircraft dimmer buss provides
control for the panel lighting.

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1.4 Operation

1.4.1 General

In addition to the general functions that are available on other FM radios, the NPX has
several features that extend its capability and make it easier to use. These features
include alphanumeric channel labeling, built -in operator help, scanning, optional guard
receiver, and numerous others.

For ease of use and operability, NAT uses a similar control layout and operating system
in the NPX138 series of radios as it does in its popular Tac/Com family of radio control
heads.

In addition to this manual, there is a help function built into the radio comprehensive
enough to address most operational questions.

1.4.2 Power On

1.4.2.1 Power-up Screen
Turn the NPX on by rotating the main (MN) volume control clockwise, away from the

‘Off’ detent position. The software revision number will briefly display, and, if enabled,
will be followed by a screen presenting an option for use of the on-line Help system.

NPX136D
S/W Ver: X.XX

To display a tutorial on the operation of the radio press the SQ/HELP button. To
advance through the tutorial press Enter after reading each screen. To exit the tutorial
press the ESC button.

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1.4.2.2 Initial Operating Display

S

If you decline ‘Help’ (by pressing the Esc button), the radio will display a summary of the
installed functions and current settings (this feature can be disabled for faster start-up).
The radio is then ready for normal operation, referred to as normal operating mode in
the remainder of this manual.

Radio Status:
Tx Mode=Duplex

1.4.3 Controls

Main On/Off/Volume

Main RX/TX Annunciator

Scan Guard Transmit

001=ABCDEFGHI W
R:173.975 067

C

Guard Volume
Guard Channel
Guard RX/TX Annunciator

Display Switch Channel Switch Squelch/Help Switch Keypad Push Buttons

1.4.3.1 Main Re ceive Volume and Power On / Off Control
To turn on the radio rotate the MN knob clockwise past the OFF detent. To turn off the
radio rotate the MN knob counterclockwise past the OFF detent. To increase the
volume of the main receiver, turn this knob clockw ise; to decrease the volume turn this
knob counterclockwise.

1.4.3.2 Guard Receive Volume
To increase the volume of the guard receiver, turn this knob clockwise; to decrease the
volume turn this knob counterclockwise. The guard receive audio cannot be turned off,
only set to a minimum level.

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1.4.3.3 Main RX/TX Status Annunciator
The main RX/TX annunciator displays the RX (Receive) and the TX (Transmit) status of
the main transceiver. When transmitting the LED will light green. When receiving any
RF signal, the LED will light amber. When idle (not receiving or transmitting), the LED
will be dark. The colour coding used for these functions corresponds to standard aircraft
FM radio conventions. Note that this is the reverse of standard vehicular conventions
used with land mobile equipment.

The receive annunciator (amber) informs the operator that the channel is active with
radio traffic of some kind. A radio that is receiving may still not produce any audio if the
analog tones or digital squelch mode present on the receive signal do not match those
set in the radio.

1.4.3.4 Guard RX/TX Status Annunciator
The guard RX/TX annunciator displays the RX (Receive) and the TX (Transmit) status
of the guard channel. When the main transceiver is transmitting on the guard channel
(SCAN / GD TX switch in GD TX position) the LED will light green. When the guard
receiver is receiving any RF signal, the LED will light amber. When idle (not receiving or
transmitting), the LED will be dark.

1.4.3.5 Change channels on the main receiver
There are two different ways to select a channel on the main transceiver.

Step or scroll through the channels using the CHAN switch. To sequentially change
channels press the CHAN switch right ‘+’ to increment by one channel or left ‘-’ to
decrement by one channel. Holding the CHAN switch in either the left or right position
causes the radio to scroll through the channels. A remote channel switch may also be
connected to the rear connector of the NPX136D to provide the same function.

Jump directly to a specific channel by pressing the keypad buttons for the required
channel and then press the Enter button.

1.4.3.6 Scanning
Turn scan mode on by putting the SCAN/GD TX switch in the SCAN position. The lower
display will show "SCANNING XXX" where XXX is the current scan mode.

Turn scan mode off by putting the SCAN/GD TX switch in the centre position.
For details on scanning operation see section tbd.

1.4.3.7 Guard Transmit
To select the guard channel for the transmit frequency put the SCAN/GD TX switch in
the GD TX position, all radio transmissions will be on the transmit frequency
programmed in the selected guard channel. To use the main transceiver's channel for
the transmit frequency put the SCAN/NORM/GD TX switch in the NORM position.

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This function only applies to radios with the guard receiver option installed. If not, the
radio will display ‘GD NOT INSTALLED’ on the upper line when the switch is set to the
GD TX position.

1.4.3.8 Guard Channel Select
Select one of two guard channels, GD1 or GD2, with the GD1 / GD2 guard channel
select switch.

1.4.3.9 Squelch Pushbutton
To disable squelch, press and release the SQ button. The first time the button is
pressed the main receiver squelch is disabled. The second time the SQ button is
pressed the guard receiver squelch is disabled. Press the SQ button a third time to
return to normal squelch operation.

When the main receiver has squelch disabled the lower display will show MN
SQUELCH DSBL or GD SQUELCH DSBL when on an analog channel; and MAIN
MONITOR or GUARD MONITOR when on a digital channel. Note that when the
squelch is disabled on a digital channel that is not receiving a digital transmission no
audio will be heard.

1.4.3.10 Using Menus
Pressing the Menu button displays the menus for the radio settings, channel edit, zone
edit, scan edit and maintenance mode. Press the Menu button to advance to the next
menu screen. Press the Enter button to display the sub-menus or editable fields under a
menu. Then press the Menu button again to advance to the next sub-menu or next
editable field. Press the Esc button to exit a menu. When any settings are changed the
operator is prompted to "Save Changes?" press the Enter button to save the changes,
press the Esc button to discard changes.

1.4.3.11 Change Radio Settings
The display brightness, transmit power for all channels, transmit mode for all channels,
analog tones on/off for all channels and digital squelch mode for all channels, as well as
the power up channel, and display options may changed from the Settings Men u. For
details see section 1.4.5.1.

1.4.3.12 Change Channel, Zone or Scan Settings
The channel settings (for both main and guard channels) the zone settings and scan
settings are accessed from the Edit Menu. For details see section 1.4.5.3.

1.4.3.13 Maintenance Menu
More detailed settings that are not normally used, or that should be changed by a
knowledgeable user, are accessed from the Maintenance Menu. For details see section

1.4.5.9.

1.4.3.14 Accessing Help Screens
Help screens are displayed when in any menu mode (but not normal operating mode.)

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