Radio Shack TRC-237 User manual

OWNER’S MANUAL Cat. No. 21-1650
TRC-237
40-Channel 5-Watt
CB Walkie Talkie
with Channel 9/19 Priorit
y
Switch
Please read before using this equipment.
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FEATURES
Your RadioShack TRC-237 40-Channel 5-
Watt CB Walkie Talkie with Channel 9/19
Priority Switch is a portable, two-way radio
you can carry almost anywhere. The chan-
nel priority switch lets you quickly switch to
either Channel 9 to report emergency situ-
ations, or to Channel 19 to transmit and re-
ceive information about road and traffic
conditions. You can use your TRC-237
around the house, in your office, or in your
car or boat. You can also use it on fishing
trips, or at your business for supervisory,
security, or warehouse personnel.
Your TRC-237 also has the following fea-
tures:
Transmit Power High/Low Switch —
lets you reduce the transceiver’s power
output during short-range transmissions
to save battery power.
Transmit Indicator — lights whenever
you press the transmit button.
Modulation Indicator — lights when you
speak into the microphone. The indicator
brightens as modulation increases.
Built-In Modulation Limiter Circuit —
automatically adjusts to a variety of voice
levels to ensure a clear transmission.
PLL (Phase-Locked-Loop) Frequency
Synthesizer — provides reliable and ex-
act tuning.
Adjustable Squelch — helps to eliminate
noise between transmissions.
©1997, 1998 Tandy Corporation.
All Rights Reserved.
RadioShack is a registered trademark
used by Tandy Corporation.
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2-Digit LED Display — lets you easily
see the selected channel number.
Automatic Noise Limiter (ANL) Circuit
— reduces noise caused by nearby elec-
trical equipment such as motors or auto-
motive ignition systems.
Battery Test Button andBatteryIndica-
tor — lets you check the batteries’ condi-
tion to find out if they need replacing.
Flexible Antenna with BNC Connector
— provides excellent reception and trans-
mission, and is designed to help prevent
antenna breakage.
Automatic Display Dimmer — the chan-
nel display automatically brightens when
you press most buttons. Then, after a few
seconds, it dims to save battery power.
Power/Charging Jack — lets you power
your TRC-237 from an AC or DC power
source,so you can use the TRC-237 with-
out draining the batteries. And, lets you
charge nickel-cadmium batteries without
removing them from the TRC-237.
Note: You need eight AA alkaline batter-
ies or ten nickel-cadmium rechargeable
batteries (not supplied) to power your
TRC-237.
We recommend you record the TRC-
237’s serial number here. The serial
number is located on the radio’s back
panel:
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FCC INFORMATION
The Federal Communications Commis-
sion (FCC) does not require you to have
a license to operate this walkie talkie.
However, the FCC does require that you
read and know Part 95 of
FCC Rules .
These rules apply to the operation of a
Class D CB. We have provided a copy of
these regulations with your TRC-237.
Internal adjustments and/or modifications
can lead to illegal operation as defined by
Part 95 of
FCC Rules . Such illegal opera-
tion can lead to very serious consequenc-
es.
To be safe and sure:
• Never open your TRC-237’s case.
• Never modify your TRC-237.
Your TRC-237 might cause TV or radio
interference even when it is operating
properly. To determine whether your
TRC-237 is causing the interference, turn
off your TRC-237. If the interference goes
away, your TRC-237 is causing it. Try to
eliminate the interference by:
• Moving your TRC-237 away from the
TV or radio
• Contacting your local RadioShack
store for help
Warning: Do not open your TRC-237 to
make any internal adjustments. Any inter-
nal adjustments should be made only by
authorized service personnel.
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CONTENTS
Powering the CB ................................ 6
Using the POWER Jack and
ALKALINE/NI-CD Switch .................. 6
Using Batteries ................................. 7
Testing the Battery Power .......... 10
Recharging Nickel-Cadmium
Batteries ..................................... 10
Using Vehicle Battery Power........... 12
Using AC Power ............................. 13
Connecting the Antenna ..................15
Connecting an
Optional Antenna ........................16
Operation .......................................... 18
Receiving Transmissions and
Adjusting Squelch .......................... 18
Transmitting .................................... 20
CB Operation Tips ........................... 21
Common Uses for a CB Radio ....... 21
Business Uses ........................... 21
Personal Uses ........................... 21
Using Common 10-Codes .............. 22
CB Courtesy ................................... 24
Maximum Range ............................ 24
Troubleshooting ............................... 25
Maintenance ..................................... 26
Specifications .................................. 27
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POWERING THE CB
You can power yourTRC-237 from any of
these sources (none supplied):
• Eight AA alkaline batteries with the
two supplied dummy batteries
• Ten rechargeable AA nickel-
cadmium batteries
• 12-volt vehicle battery power using a
fused power cord
• Standard AC power using a power
supply
USING THE POWER JACK
AND ALKALINE/NI-CD
SWITCH
The POWER jack lets you connect an ex-
ternal power source (such as your vehi-
cle’s battery power or AC power), or
connect a battery charger to charge
nickel-cadmium batteries while they are in
the TRC-237.
The TRC-237 also has a slide switch (AL-
KALINE/NI-CD) inside the battery com-
partment that you must set correctly,
depending on what power source you are
using and whether or not you want to
charge rechargeable batteries while they
are in the TRC-237.
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•SetittoALKALINE before you con-
nect an external power source (vehi-
cle battery power or AC adapter) to
the POWER jack or while you are us-
ing internal batteries (alkaline or re-
chargeable).
•SetittoNI-CD
only when you con-
nect a battery charger to the POWER
jack to charge the installed recharge-
able batteries.
Warning: To avoid injuring yourself or
damaging the TRC-237, connect a bat-
tery charger to the POWER jack
only
when nickel-cadmium batteries are in-
stalled (see “Recharging Nickel-Cadmium
Batteries” on Page 10). Never try to re-
charge non-rechargeable batteries. They
could get very hot and explode.
Note: You can connect an external pow-
er source for power regardless of the type
of batteries you installed.
USING BATTERIES
You can power the TRC-237 from eight
AA alkaline batteries (such as Ra-
dioShack Cat. No. 23-552) with the two
supplied dummy batteries, or 10 re-
chargeable AA nickel-cadmium batteries
(such as Cat. No. 23-125).
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Cautions:
• Always use fresh, or freshly charged,
batteries of the required size and
recommended type.
• Do not mix old and new batteries,
different types of batteries (stan-
dard, alkaline, or rechargeable
nickel-cadmium), or rechargeable
batteries of different capacities.
Follow these steps to install the batteries.
1. If the TRC-237 is on, turn OFF/VOLUME
fully counterclockwise until it clicks to
turn it off.
2. Slide the strap on the back of the
TRC-237 through the buckle and the
battery compartment cover to re-
move it.
3. Slide the battery compartment cover
in the direction of the arrows to
remove it.
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4. Be sure ALKALINE/NI-CD inside the
battery compartment is set to ALKA-
LINE.
5. Put eight AA alkaline batteries and
the two supplied dummy batteries, or
ten AA nickel-cadmium batteries into
the battery compartment, as indi-
cated by the polarity symbols (+ and
–) marked inside.
Note: Before you use the TRC-237
with nickel-cadmium batteries, you
need to charge the batteries (see
“Recharging Nickel-Cadmium Batter-
ies” on Page 10).
6. Replace the battery compartment
cover and the strap on the back of
the TRC-237.
Cautions:
• If you will not be powering the TRC-
237 from internal batteries for sev-
eral months, remove the batteries.
• Dispose of old batteries promptly
and properly.
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Testing the Battery Power
1. Turn on the TRC-237 by rotating
OFF/VOLUME clockwise until it clicks.
2. Hold down BATT TEST. If the indica-
tor lights, there is enough battery
power to operate the CB. If the indi-
cator is dim or does not light, replace
or recharge the batteries.
Recharging Nickel-Cadmium
Batteries
You can use a battery charger, Cat. No.
23-249 (not supplied), to charge or re-
charge nickel-cadmium batteries while
they are inside the TRC-237’s battery
compartment.
Do not use the TRC-237 while you are
charging the nickel-cadmium batteries.
Cautions:
• Use only the recommended battery
charger to recharge the batteries in
the TRC-237. Other chargers could
damage your TRC-237 or the batter-
ies.
• Be careful not to overcharge nickel-
cadmium batteries.
• To prevent damage to rechargeable
nickel-cadmium batteries, never
charge them in an area where the
temperature is above 90°F (32°C) or
below 40°F (4.5°C).
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