Radio Shack HTX-252 User Guide

Cat. No. 19-1127

OWNER’S MANUAL

Please read before using this equipment.

HTX-252

2–Meter Amateur

FM Mobile Transceiver

FEATURES

Your RadioShack HTX-252 2–Meter FM Mobile Transceiver is a
compact and versatile transceiver, perfect either in your vehicle
or in your home. Vehicle cables and mounting hardware are sup­plied. Add an optional base-station antenna, cable, an d a power
supply to make it your home transceiver. It is an all-around ideal
choice for your amateur communications needs.

: You must have a Technician Class or higher Amateur Ra-

Note

dio Operator’s License and a call sign issued by the FCC to legal­ly transmit using this transceiver. Transmitting without a license
carries heavy penalties. Getting a license is easier than ever. See
“Introduction to Amateur Radio” on Page 7 for more information.

Here are some of your transceiver’s features.

High (25 Watt) and Low (10 Watt) Power Settings

— let you se­lect the best power setting according to communication guide­lines.

10 Memory Channels and 1 Call Channel

— let you store up to
10 frequencies for quick access along with other settings such as
the repeater offset and the CTCSS tones.

Frequency Range of 144–148 MHz (TX) and 136–174 MHz
(RX) —

provide flexibility and excellent wide coverage. You can

also extend the transmit frequency range to 142.00–

149.885MHz.

Channel Up/Down and 16-Key DTMF on the Mic

— lets you
manually send DTMF (Dual-Tone, Multiple Frequency) tones to
quickly access DTMF-access repeaters, autopatches, or other
stations equipped with a DTMF page feature.

CTCSS
Tone

(Continuous Tone Coded Squelch System)

Subaudible

— both encodes and decodes 38 subaudible tones to help
reduce interference from other nearby systems operating on the
same frequency.

©2000 Tandy Corporation.

RadioShack is a registered trademark used by Tandy Corporation.

All Rights Reserved.

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Programmable Frequency Step

step for tuning or scanning to 5, 10, 12.5, 15, 20, 25 kHz.

— lets you set the frequency

Signal Strength Indicator

strength of the received signal and transmitting signal.

Digital Phase-Locked Loop (PLL) Frequency Synthesizer

provides highly accurate and stable tuning.

Built-In Automatic Modulation Control

RF modulation level.

Repeater Offset

match a local repeater.

— the transceiver scans the frequency range and the mem-

Scan

ory locations for transmissions.

Rotary Tuning

accurately.

External Speaker Jack

speaker for more flexible operation.

Illuminated Digital Display

functions, and the signal strength.

Key Lock

dentally changing settings.

— lets you select the appropriate offset value to

— lets you reach a desired frequency quickly and

— lets you lock the transceiver’s keys to prevent acci-

— a graduated bar shows the relative

— ensures a constant

— lets you connect an optional external

— clearly shows the frequency, the

—

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MANUAL CONVENTIONS

Some of your transceiver’s controls perform multiple functions.
The abbreviation or symbol for a function is printed on, or above
each multi-function button.

To activate certain transceiver features, you must press F (func­tion) and then another button. Those key combination instru c­tions are printed as the first button name, +, then the second
button name. For example,

LOCK.

Control names are printed in small, bold, capital letters such as

or

CALL

display are printed using a distinctive typeface, such as

BUSY

or

. Words, symbols, and numbers that appear on the

VFO

.

F+LOCK

means press F then press

146.94

FCC INFORMATION

This device complies with Part 15 of the
subject to the following two conditions: (1) This device may not
cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause un­desired operation.

4

FCC Rules

. Operation is

CONTENTS

Introduction to Amateur Radio ............................................. 7

Preparation ........................................................ ... .................. 9

Attaching the Microphone Holder ..................................... 9

Mounting the Transceiver ................................................. 9

Connecting an Antenna ................................................... 11

Connecting the Microphone ............................................ 12

Using an External Speaker ............................................. 12

Connecting Power .......................................................... 13

Using the Transceiver as a Base Station ........................ 13

A Quick Look at the Controls ............................................. 15

A Quick Look at the Display ............................................... 18

Operation .............................................................................. 19

Turning the Transceiver On and Off ................................ 19

Selecting Frequencies .................................................... 19

Receiving Transmissions ................................................ 20

Transmitting .................................................................... 20

Understanding Repeaters ................................................... 22

Setting the Repeater Offset Frequency .......................... 23

Setting the Repeater Offset Direction ............................. 23

Reversing the Transmit and Receive Frequencies ......... 24

Memory Operation ............................................................... 25

Storing a Transmit/Receive Frequency ........................... 25

Recalling Memories ........................................................ 25

Using the Calling-Frequency Memory ............................ 26

Scanning Operation ............................................................. 27

Scanning for Active Frequencies .................................... 27

Scanning Standard Memory Locations ........................... 27

Continuous Tone Coded Squelch System Features ......... 28

Temporarily Opening Squelch ......................................... 28

Using DTMF Tones ............................................................... 30

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Other Special features ......................................................... 31

Using Priority Frequency Monitor .................................... 31

Using VFO Priority ................................................... 31

Using Memory Priority .............................................. 31

Changing the Transmit Frequency Range ...................... 32

Selecting the Transmit Power Level ................................ 32

Locking the Keypad ......................................................... 32

Turning the Key Tone On and Off .................................... 33

Setting the Frequency Step ............................................. 33

Reducing Interference ..................................................... 33

Troubleshooting ................................................................... 35

Care and Maintenance ......................................................... 36

Resetting the Transceiver ............................................... 37

Replacing the In-Line Fuse ............................................. 37

Specifications ....................................................................... 38

6

INTRODUCTION TO AMATEUR RADIO

This transceiver is the perfect first radio for anyone entering the
exciting world of amateur radio, as well as a great additional
transceiver for the experienced amateur radio operator. This
transceiver opens a door for you to the world from almost any­where! All you need is an Amateur Radio Operator’s License
(Technician Class or higher) issued by the Federal Communica­tions Commission (FCC). If you do not have a license, it is easier
than ever to get one, and help from licensed operators is avail­able. Here are a few tips to help you get started.

You can turn on your transceiver and scan the entire band to hear
what is going on;

you get your license

in violation of federal law that can lead to severe penalties. Note
that ham operators take the FCC rules very seriously and want
nothing to do with “bootleggers” — their term for people who op­erate without a license.

Find out if there is a ham radio club in your area. Most clubs wel­come newcomers and are glad to help you get your license.
There are thousands of clubs across the country, so there is prob­ably one in or near your community. The staff at your local Ra­dioShack store often can help you locate a club.

If you do not hear anyone talking about a local clu b as you listen
to local transmissions, write to the American Radio Relay League
(ARRL) at the following address to find out how to contact a local
affiliate. The ARRL is the national organization representing am­ateur radio in the United States. The league has more than
150,000 members. Most are ham operators, or members in the
process of obtaining their license.

however, do not attempt to transmit until

. If you transmit without a license, you are

The American Radio Relay League

225 Main Street

Newington, CT 06111

http://www.arrl.org

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Start studying for the license exams. Do not be intimidated by the
word “study,” because most people can go from knowing abso­lutely nothing about amateur radio to passing the Novice and
Technician written exams in less than a month.

The exams test your knowledge of basic radio regulations and el­ementary radio theory. Many clubs hold license classes which
can be a fun and easy way to learn about amateur rad io. There
are good books, cassette tapes, computer programs, and many
other study aids available. Your local RadioShack store sells

License Preparation

censes. While you are no longer required to learn Morse code for
a Technician Class license, we encourage you to learn it anyway
so you can advance to higher levels of operating privileges.

There is no fee to take the Novice exam. As soon as you pass the
Novice exam, you can immediately take the Technician exam.
There is a small fee required for taking the Technician exam. All
license level tests are administered by a three-member Volunteer
Examiner Team. Contact the ARRL for a schedule of exam op­portunities in your area.

The Technician Class license lets you use this transceiver to
communicate directly with other operators, and use repeaters for
distant communication.

Amateur radio is a great hobby that has enriched the lives of mil­lions of people all over the world. The ARRL would be glad to hear
from you if you need more information or would like to join!

study guides for amateur radio operator li-

FCC

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PREPARATION

ATTACHING THE
MICROPHONE HOLDER

Follow these steps to attach the
microphone holder to your vehicle.

1. Using the holder as a tem-

plate, mark the position for the
mounting screw holes at the
desired location.

2. At each marked position, drill

a hole slightly smaller than the
supplied mounting screw.

Caution:

into anything behind the
mounting surface.

3. Use a Phillips screwdriver to attach the holder to the mount-

ing location with the supplied small self-tapping sh eet metal
screws and lock-washers.

MOUNTING THE TRANSCEIVER

Be careful not to drill

The most common mounting location for this transceiver is under
a vehicle’s dashboard. However, if you plan to use the transceiver
as a base station, you can place it on a desk, shelf, or table (see
“Using the Transceiver as a Base Station” on Page 13).

If you are mounting the transceiver in a vehicle, choose a loca­tion where:

• you can easily reach the transceiver

• wires and cables are clear of the vehicle’s pedals or other
moving parts

• the transceiver is not directly in front of heating vents

• all wires and cables can reach their connection points

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Caution:

If you use the transceiver in a vehicle, mount it securely
to avoid damage to the transceiver or vehicle, or injury to anyone
in the vehicle during sudden starts or stops.

Follow these steps to mount the transceiver.

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1. Using the mounting bracket as a template, mark the posi­tions for the screw holes on the mounting surface,

2. In each marked location, drill a hole slightly smaller than the
supplied self-tapping screws.

Caution:

Be care not to drill into objects behind the mount-

ing surface.

3. Using a Phillips screwdriver, attach the mounting bracket to
the mounting surface with the supplied mounting screws
and flat washers.

4. Attach the transceiver to the mounting bracket using the
supplied rubber washers and mounting knobs.

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CONNECTING AN ANTENNA

You must install an antenna before you can operate the trans­ceiver. There are many different types of antennas suita ble for
transceiver use. Each has its own benefits, Choose the one best
suited to your particular needs. Your local RadioShack store has
a wide selection from which to choose.

If you are using the transceiver as a base station, see “Us-

Note:

ing the Transceiver as a Base Station” on Page 13.
When you install an antenna, keep in mind that, for the best per-

formance, you should mount the antenna vertically as high as
possible on the vehicle and away from sources of electrical noise.

Once you choose an antenna, follow it’s mounting instructions.
Then route the cable to the transceiver and thread the cable onto
the

Cautions:

To take advantage of your transceiver’s maximum range, adjust
the antenna’s standing wave ratio (SWR) using an SWR meter
(not supplied, available at your local RadioShack store). Follow
the instructions supplied with the SWR meter and antenna to ad­just the antenna’s SWR. Values of 2.0:1 are generally accept­able, with readings of 1.5:1 or lower being more desirable.

connector on the back of the transceiver.

ANT

• Avoid routing the cable next to sharp edges or moving
parts, which might damage the cable.

• Do not run the cable next to power cables or other ra dio
antenna cables.

• Do not run the cable through the engine compartment or
other areas that produce extreme heat.

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CONNECTING THE MICROPHONE

1. Align the notch of the
microphone’s plug and
the microphone’s jack,

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located on the left side of
the front panel. Then
insert the plug and turn
the metal ring clockwise
to secure the plug.

2. Slide the microphone onto the microphone holder.

To disconnect the microphone from the transceiver, turn the met­al ring counterclockwise to loosen it.

Caution:

Always disconnect the microphone by grasping its plug.

Never pull on the coiled microphone cable.

USING AN EXTERNAL SPEAKER

To hear your communications better in a noisy environment, you
can plug an optional, external speaker into the transceiver. The
speaker should have an impedance of 8-ohms and be able to
handle 3 to 10 watts of power. The speaker’s cable should have

1

/8-inch (3.5-mm) plug.

a
To connect the speaker, insert the speaker cable’s plug into

on the back of the transceiver. This automatically disconnects

SP

the built-in speaker.

EXT.

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