Radio Shack TRC-502 User manual

Cat. No. 21-1702
OWNER’S MANUAL
Please read before using this equipment.
TRC-502
40-Channel Mini Mobile CB Radio
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2
FEATURES
Your RadioShack TRC-502 40-Channel
Mini Mobile CB Radio is a great way to
communicate with other CB radio opera-
tors. Because of its convenient compact
size, you can use it just about anywhere.
You can mount it in a vehicle for mobile
use, or in your home or office for use as
a base station.
Your CB has these advanced features.
Up/Down Channel Selector — lets you
easily select a channel with the press of
a button.
TX (Transmit) Indicator — lights to
show when the CB is transmitting.
Automatic Noise Limiter (ANL) Circuit
— reduces impulse-type noise during
reception.
5-Pin Din Mic Connector — uses five
prongs to reinforce a clear connection
between the mic and the receiver.
Full Le
g
al Power — gives you the full
range of CB channels with the maximum
allowed transmit power.
Ad
j
ustable Squelch — helps to elimi-
nate noise between transmissions.
Automatic Modulation — prevents the
transmitter signal from over-modulating
and distorting.
(PLL) Frequenc
y
S
y
nthesizer — pro-
vides highly accurate and stable tuning.
Cr
y
stal-Controlled Di
g
ital Tunin
g
—
provides precise transmission tuning ca-
pability when selecting a channel.
Two Ceramic Filters — provide superi-
or channel selectivity and prevent adja-
cent channel interference.
Universal Mountin
g
Bracket — lets
you mount your CB securely in your ve-
hicle, or on a table or shelf in your home
or office.
External Antenna Jack — lets you at-
tach an optional antenna to your CB ra-
dio for increased range.
We recommend you record your CB’s
serial number here. The number is on
the bottom of the CB.
Serial Number: ___________________
© 1998 Tandy Corporation.
All Rights Reserved.
RadioShack is a registered trademark used by Tandy Corporation.
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FCC INFORMATION
The Federal Communications Commis-
sion (FCC) does not require you to have
a license to operate this CB radio. How-
ever, you must know Part 95 of
FCC
Rules
. These rules apply to the opera-
tion of a Class D CB. We have provided
a copy of these regulations with your CB
radio.
Warning: Do not open your CB radio to
make any internal adjustments. A CB ra-
dio is set up to transmit a regulated sig-
nal on an assigned frequency. It is
against the law to alter or adjust the set-
tings inside the unit to exceed these lim-
itations.
To be safe and sure:
• never open your CB radio’s cases.
• never change or replace anything in
your CB radio.
Your CB radio might cause TV or radio
interference even when it is operating
properly. To determine whether your CB
radio is causing the interference, turn off
your CB radio. If the interference goes
away, your CB is causing it. Try to elimi-
nate the interference by:
• moving your CB radio away from the
TV or radio
• contacting your local RadioShack
store for help
If you can not eliminate the interference,
the FCC requires that you stop using
your CB radio.
This device complies with Part 95 of
FCC Rules
. Operation is subject to the
following two conditions: 1) this device
may not cause harmful interference, and
2) this device must accept any interfer-
ence received, including interference
that may cause undesired operation.
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CONTENTS
Installation ............................................................................................................... 5
Mounting the Microphone Holder ....................................................................... 5
Mounting the CB ................................................................................................. 5
Connecting an Antenna ...................................................................................... 6
Connecting the Microphone ................................................................................ 7
Using Vehicle Battery Power .............................................................................. 8
Using the CB as a Base Station ......................................................................... 8
Operation ............................................................................................................... 10
Receiving Transmissions and Adjusting Squelch ............................................. 10
Transmitting ...................................................................................................... 11
Operational Hints .................................................................................................. 12
Common Uses for a CB .................................................................................... 12
Personal Uses ............................................................................................ 12
Business Uses ........................................................................................... 12
Transmission Courtesy ..................................................................................... 12
Using Common 10-Codes ................................................................................ 13
Maximum Range .............................................................................................. 14
Reducing Noise ................................................................................................ 14
Troubleshootin
g
.................................................................................................... 15
Care and Maintenance .......................................................................................... 16
Replacing the Fuse ........................................................................................... 17
Specifications ........................................................................................................ 18
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INSTALLATION
MOUNTING THE
MICROPHONE HOLDER
You can mount the microphone holder
to either side of the CB or to another lo-
cation near your receiver.
Caution: Do not mount the CB micro-
phone holder where it could damage or
interfere with the operation of any pas-
sive restraint safety device (an airbag or
seat belt).
To mount the holder to either side of the
CB, use the two supplied 1/8-inch (3-mm)
machine screws, plain washers, and
spring washers as shown to secure the
holder.
To mount the holder near the receiver in
another location in your vehicle (such as
a dashboard), or somewhere in your
home or office, such as a nearby wall,
follow these steps.
1. Using the holder as a template,
mark the positions for the screw
holes at the desired location.
2. At each marked position, drill a hole
slightly smaller than the mounting
screws.
Caution: Be careful not to drill into
anything behind the mounting sur-
face.
3. Mount the holder using the machine
screws, spring washers, plain wash-
ers and nuts.
Note: If you cannot reach behind the
mounting surface to attach the nuts to
the machine screws, use the two sup-
plied 1/8-inch (3-mm) screws and plain
washers.
MOUNTING THE CB
The most common mounting location for
this CB is under a vehicle’s dashboard.
However, if you use the TRC-502 as a
base station in your home or office, you
can place it on a desk, shelf, or table
(see “Using the CB as a Base Station”
on Page 8).
If you are mounting the CB in a vehicle,
choose a location where:
• you can easily reach the CB.
• wires and cables are clear of the
vehicle’s pedals and other moving
parts.
Mounting Surface
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6
• the CB is not directly in front of heat-
ing vents.
• all wires and cables can reach their
connection point.
Cautions:
• If you use the CB in a vehicle,
mount it securely to avoid damage
to the CB or vehicle or injury to pas-
sengers.
• Do not mount the CB where it could
damage or interfere with the opera-
tion of any passive restraint safety
device (an airbag or seatbelt).
Follow these steps to mount the CB us-
ing the supplied hardware.
1. Using the mounting bracket as a
template, mark the positions for the
screw holes on the mounting sur-
face.
2. In each marked location, drill a hole
slightly smaller than the two 1/5-inch
(5-mm) mounting screws.
Caution: Be careful not to drill into
objects behind the mounting sur-
face.
3. Mount the bracket to the mounting
surface with the 1/5-inch (5-mm)
mounting screws, spring washers,
plain washers, and nuts.
Note: If you cannot reach behind
the mounting surface to attach the
nuts on the bolts, use the 1/5-inch (5-
mm) mounting screws and plain
washers to secure the bracket.
4. Attach the CB to the mounting
bracket using the two rubber wash-
ers and mounting knobs.
CONNECTING AN
ANTENNA
There are many different types of anten-
nas for mobile CBs, each with its own
benefits. You can choose one that best
fits your needs. Your local RadioShack
store sells a wide variety of antennas.
Note: If you are using this CB as a base
station, see “Using the CB as a Base
Station” on Page 8.
Mounting
Surface
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7
When you choose an antenna, keep in
mind that, for the best performance, you
should mount the antenna:
• as high as possible on your vehicle,
home or building
• as far as possible from source of
electrical noise
• vertically
Once you choose an antenna, follow its
mounting instructions. Then route the
cable to the CB and connect the cable to
ANTENNA on the back of the CB.
Cautions:
• 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 radio antenna
cables.
• Do not run the cable through a vehi-
cle’s engine compartment or other
areas that produce extreme heat.
To take advantage of your radio’s maxi-
mum range, adjust the antenna’s Stand-
ing Wave Ratio (SWR) using an SWR
meter (such as Cat. No. 21-523).
Follow the instructions supplied with the
SWR meter and antenna to adjust your
antenna’s SWR to the lowest possible
value. SWR values of 2.0:1 are general-
ly acceptable, with readings of 1.5:1 or
lower being more desirable.
CONNECTING THE
MICROPHONE
1. Press the plastic tab on the top of
the supplied microphone’s plug and
align the 5-pin DIN microphone plug
with the corresponding pin holes in
the CB’s MIC jack. Then push the
plug into the mic jack.
2. Slide the microphone onto the
microphone holder.
To disconnect the microphone from the
CB, press the plastic tab on the side of
the plug, then pull out the plug.
Caution: Never pull on the microphone
cable.
Tab
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8
USING VEHICLEBATTERY
POWER
Follow these steps to connect the CB to
vehicle battery power.
1. Connect the red wire (with in line
fuse holder) to a point in your vehi-
cle’s fuse block that has power only
when the ignition is in the ACC or
ON position.
2. Connect the black wire to a metal
part of the vehicle’s frame (chassis
ground).
Caution: Do not connect the black
wire to a non-metallic (plastic) part,
or to any part insulated from the
vehicle’s chassis by a non-metallic
part.
USING THE CB AS A
BASE STATION
Although this CB radio is designed
mainly for mobile use, you can also use
it as a base station with an AC power
source. For base station installation, you
need these items:
• a 13.8V DC power supply that can
supply at least 1.5 amps (such as
Cat. No. 22-504)
Caution: Most 13.8V DC power
supplies plug into a standard AC
outlet to produce DC power. Before
connecting your CB to a 13.8V DC
power supply, read and follow the
instructions included with the power
supply.
• base station antenna (such as Cat.
No. 21-969)
• coaxial antenna cable and connec-
tor (available at your local
RadioShack store)
Warning: Use extreme caution when
you install or remove a base station CB
antenna. 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, ca-
ble or guy wires can cause electrocution
and death. Call the power company to
remove the antenna. Do not attempt to
remove it yourself!
Red Wire to
Switched ACC
Terminal
Black Wire to
Ground
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Follow these steps to install the CB as a
base station.
1. Mount the base station antenna as
described in it’s owner’s manual.
2. Connect the antenna to ANTENNA.
3. Connect the CB’s black power wire
to the negative (–) terminal on the
DC power supply.
4. Connect the CB’s red wire to the
positive (+) terminal on the DC
power supply.
5. Connect the DC power supply to a
standard AC outlet.
Caution: To prevent damage to the CB,
be sure you connect an antenna and the
microphone before you use the CB.
Black Wire
to Ne
g
ative
Red Wire
to Positive
Antenna
Terminal of
DC Power
Terminal of
DC Power
Suppl
y
Suppl
y
Wire
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10
OPERATION
Before you use your CB, you should
know how to use it effectively and cour-
teously. “Operational Hints” on Page 12
contains information that will help you
get more enjoyment from our CB.
RECEIVING
TRANSMISSIONS AND
ADJUSTING SQUELCH
1. Turn SQUELCH fully counterclock-
wise.
2. Turn on the CB by turning VOLUME
clockwise until it clicks. The channel
display lights and the channel num-
ber appears.
3. Press or on the base
to select the desired channel.
4. Adjust VOLUME to a comfortable lis-
tening level.
5. To cut out background noise
between transmissions, wait until
there is no signal, then slowly turn
SQUELCH clockwise until the back-
ground noise stops.
Note: To receive very weak signals,
turn SQUELCH counterclockwise.
You hear noise between transmis-
sions, but you also hear weak trans-
missions.
6. To turn off the CB, turn VOLUME
counterclockwise until you hear it
click. The channel display turns off.
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