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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2
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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Follow these steps to charge nickel-
cadmium batteries in the TRC-237.
1. If the TRC-237 is on, turn OFF/VOLUME
fully counterclockwise until it clicks to
turn it off.
2. Set ALKALINE/NI-CD inside the bat-
tery compartment to NI-CD (see “Us-
ing the Power Jack and ALKALINE/
NI-CD Switch” on Page 6).
3. Connect the battery charger’s 5.5
mm outer diameter./2.1 mm inner
diameter barrel plug to the POWER
jack on the side of the TRC-237,
then plug the battery charger’s plug
into a standard AC outlet.
It takes about 24 hours to charge
new or fully discharged nickel-
cadmium batteries. Subsequent
charges take about 16 to 18 hours.
4. When charging is complete, unplug
the battery charger’s plug from the
AC outlet. Then disconnect the bat-
tery charger’s barrel plug from the
POWER jack.
5. If the TRC-237 is on, turn OFF/VOLUME
fully counterclockwise until it clicks to
turn it off. Then set ALKALINE/NI-CD
to ALKALINE.
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Note: You can use an external charger
(such as Cat. No. 23-134, not sup-
plied) to recharge the nickel-cadmium
batteries. After removing the batteries
from the TRC-237, follow the instructions
that come with the external charger.
Important: Your TRC-237 is capable of
using nickel-cadmium batteries. At the end
of the batteries’ useful life, they must be re-
cycled or disposed of properly. Contact
your local, county, or state hazardous
waste management authorities for informa-
tion on recycling or disposal programs in
your area. Some options that might be
available are: municipal curbside collec-
tion, drop-off boxes at retailers such as
your local RadioShack store, recycling col-
lection centers, and mail-back programs.
USING VEHICLE BATTERY
POWER
You can power your TRC-237 from your
vehicle’s cigarette-lighter socket with an
optional 12-volt DC fused power cord
(such as Cat. No. 270-1533).
Cautions:
• You must use a DC fused cord that
supplies 12 volts and delivers at
least 1200 milliamps of vehicle
power. Its center tip must be set to
positive, and its plug must correctly
fit the TRC-237’s POWER jack. The
recommended fused cord meets
these specifications. Using a fused
cord that does not meet these speci-
fications could damage the TRC-237
or the fused cord.
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• When you finish using the TRC-237,
unplug the fused cord from the ciga-
rette-lighter socket before you dis-
connect it from your TRC-237.
1. If the TRC-237 is on, turn OFF/VOL-
UME fully counterclockwise until it
clicks to turn it off.
2. Be sure ALKALINE/NI-CD inside the
battery compartment is set to ALKA-
LINE.
3. Insert the power cord’s 5.5 mm outer
diameter/2.1 mm inner diameter bar-
rel plug into the POWER jack.
4. Plug the power cord’s other end into
your vehicle’s cigarette-lighter socket.
Note: If the TRC-237 does not operate
when you use the DC power cord, unplug
the cord from the cigarette-lighter socket
and clean any ashes or debris from the
socket. If your TRC-237 still does not
work, check the fuse in the DC power cord
and replace it if necessary.
USING AC POWER
You can power your TRC-237 from stan-
dard AC power using an optional AC-to-
12 V DC power supply (such as Cat. No.
22-504) and an optional DC fused power
cord (such as Cat. No. 270-1533).
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Cautions:
• The power supply must be able to
deliver 12 volts and at least 1200 mil-
liamps of power. The recommended
power supply meets these specifica-
tions. Using a power supply that
does not meet these specifications
could damage the TRC-237 or the
power supply.
• You must use a DC fused cord that
supplies 12 volts and delivers at
least 1200 milliamps of power. Its
center tip must be set to positive,
and its barrel plug must correctly fit
the TRC-237’s POWER jack. The rec-
ommended fused cord meets these
specifications. Using a fused cord
that does not meet these specifica-
tions could damage the TRC-237 or
the fused cord.
• To help prevent an electrical short,
unplug the DC fused cord’s plug from
the AC adapter’s power socket be-
fore you unplug the cord’s barrel plug
from the TRC-237.
Follow these steps to connect the TRC-
237 to AC power.
1. If the TRC-237 is on, turn OFF/VOL-
UME fully counterclockwise until it
clicks to turn it off.
2. Connect the DC fused cord’s 5.5 mm
outer diameter/2.1 mm inner diame-
ter barrel plug to the TRC-237’s
POWER jack.
3. Be sure ALKALINE/NI-CD inside the
battery compartment is set to ALKA-
LINE.
4. Plug the DC fused cord’s other end
into the power supply’s power socket.
5. Plug the power supply into a stan-
dard AC outlet, then turn on the pow-
er supply.
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Note: If the TRC-237 does not operate
when you use the DC fused cord, turn the
power supply off, unplug the cord from the
power supply’s power socket, then clean
any debris from the socket. If your TRC-
237 still does not work, check the fuse in
the DC fused cord and replace it if neces-
sary.
CONNECTING THE
ANTENNA
Caution: To prevent damage to your
TRC-237, you must connect an antenna
before you operate it.
Follow these steps to attach the supplied
flexible antenna to your TRC-237.
1. Align the slots around the antenna’s
connector with the tabs on the
antenna jack on top of the TRC-237.
2. Press the antenna down over the
jack and turn the antenna’s base
clockwise until it locks into place.
To remove the antenna, turn the anten-
na’s base counterclockwise until it un-
locks, then lift it off the antenna jack.
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Connecting an Optional
Antenna
Your walkie talkie comes with a flexible
antenna that is ideal for most applications.
However, the walkie talkie’s antenna jack
makes it easy to connect other types of
antennas, too. For mobile or base station
use, you might want to connect an option-
al external antenna. Your local Ra-
dioShack store carries a wide selection of
external mobile or outdoor base-
station antennas. Choose the one that
best meets your needs.
When deciding on a mobile or base-
station antenna and its location, consider
the following:
• The location of the antenna should
be as high as possible.
• The antenna and antenna cable
should be as far as possible from
sources of electrical noise (appli-
ances, other radios, and so on).
• The antenna should be vertical for
the best performance.
Note: When connecting an optional an-
tenna, always use 50-ohm coaxial cable,
such as RG-58 or RG-8. For lengths over
50 feet, use RG-8 low-loss dielectric coax-
ial cable. If the coaxial cable’s connector
does not fit into the antenna jack, you
might also need a PL-259-to-BNC anten-
na plug adapter, such as Cat. No. 278-
120. Your local RadioShack store carries
a wide variety of coaxial antenna cable
and connectors.
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Follow the installation instructions sup-
plied with the antenna, route the antenna
cable to the TRC-237, then connect it to
the antenna jack.
Cautions:
• Do not run the cable over sharp
edges or moving parts.
• Do not run the cable next to power
cables or other CB antenna cables.
• Do not run the cable through a vehi-
cle’s engine compartment or other
areas that produce extreme heat.
• Follow all cautions and warnings
included with the antenna.
Warning: When installing or removing a
base station CB antenna, use extreme
caution. If the antenna starts to fall, let it
go! It could contact overhead power lines.
If the antenna touches the power line,
contact with the antenna, mast, cable or
guy wires can cause electrocution and
death! Call the power company to remove
the antenna. DO NOT attempt to do so
yourself.
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OPERATION
Before you use your TRC-237, we recom-
mend you read “CB Operation Tips” on
Page 21, which contains information to
help you use it effectively and courteously.
RECEIVING
TRANSMISSIONS AND
ADJUSTING SQUELCH
1. If you did not connect an external
antenna, hold the TRC-237 so the
antenna is vertical.
2. Turn on the TRC-237 by turning OFF/
VOLUME clockwise until you hear a
click and a hissing sound.
3. Set OUT –CH9 –CH19 on top of the
TRC-237 for the channel you want to
tune:
• To quickly tune to Channel 9, set it
to CH9. 9flashes on the display.
• To quickly tune to Channel 19, set
it to CH19. 19 flashes on the dis-
play.
• To tune to any channel other than
Channel 9 or Channel 19, set it to
OUT. The previously selected
channel number appears on the
display.
Note: When you tune a channel, the
channel’s number appears or flashes
on the display for about 20 seconds
then fades, to save battery power. To
continuously display the channel
number, press and hold DISPLAY on
the side of the TRC-237.
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To redisplay the channel number for
about 20 seconds, simply press and
release DISPLAY.
4. If you set OUT –CH9 –CH19 to OUT,
repeatedly press CH s to select
higher channels, or CH t to select
lower channels. To move rapidly
through the channels, hold down CH
s or t.
5. Adjust OFF/VOLUME to a comfortable
listening level.
6. Adjust SQUELCH to cut out the back-
ground noise. Wait until there is no
signal on the channel, then slowly
turn SQUELCH clockwise until the
background noise stops.
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Note: Do not turn SQUELCH too far
clockwise because you might also
cut out weak signals.
7. To turn off the TRC-237, turn OFF/
VOLUME toward OFF until it clicks.
TRANSMITTING
1. Follow Steps 1–6 in “Receiving
Transmissions and Adjusting
Squelch” on Page 18.
2. Hold the TRC-237 2 to 3 inches from
your mouth. Press and hold PUSH TO
TALK on the side of the TRC-237. TX
on the front of the TRC-237 lights.
Speak into the microphone. MOD
lights.
When you finish speaking, release
the button. TX and MOD turn off.
Note: Do not speak too loudly when
transmitting. It does not make your
signal any stronger, and might distort
your transmission.
Important: Channel 9 is reserved for
motorist assistance and for reporting
emergency information about acci-
dents, hazardous road conditions,
and so on. If you are using Channel
9, always give emergency messages
priority.
3. To turn off the TRC-237, turn OFF/
VOLUME toward OFF until it clicks.
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