Radio Shack TRC-503 User manual

Cat. No. 21-1703
OWNER’S MANUAL
Please read before using this equipment.
40 Channel Mobile CB Radio
with Channel 9/19 Priority Switch
A
TRC-503
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FEATURES
Your RadioShack TRC-503 40 Channel
Mobile CB Radio is a breakthrough in
CB design technology. You can mount it
in a vehicle for mobile use, or in your
home for use as a base station. Your CB
has these advanced features:
Emergency Channel Switch — lets
you quickly switch to Channel 9 or
Channel 19 so you can monitor or report
emergency situations.
TX and RX Indicators — light to show
when the radio is transmitting or receiv-
ing.
Full Legal Power — gives you the
greatest available range.
Automatic Noise Limiter — reduces
impulse-type noises while receiving.
External Speaker Jack — lets you con-
nect your CB to an external speaker.
Phase-Locked Loop (PLL) Frequency
Synthesizer — provides highly accurate
and stable tuning.
Two Built-In Ceramic Filters — ensure
superior channel selectivity and freedom
from adjacent channel interference.
Automatic Modulation Control — pre-
vents the transmitter signal from over-
modulating and distorting.
Universal Mounting Bracket — lets
you mount your CB securely in your ve-
hicle or on a table or shelf in your home.
Note: To use this CB, you must connect
a mobile or base station antenna. Your
local RadioShack store has a wide vari-
ety of antennas. For more information,
see “Connecting an Antenna” on
Page 6.
We recommend you record your CB’s
serial number here. The number is on
the CB’s bottom cabinet.
Serial Number _________________
©1998, 1999 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
. It explains the proper operation of
a Class D citizen’s band transceiver. We
enclosed a copy of Part 95 with your CB
radio.
Warning: Do not open the 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 case.
• 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
is causing the interference, turn off your
CB. If the interference goes away, your
CB is causing it. Try to eliminate the in-
terference by:
• moving your CB radio away from the
receiver
• contacting your local RadioShack
store for help
This device complies with Part 15 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
Attaching the Microphone Holder ....................................................................... 5
Mounting the Transceiver .................................................................................... 5
Connecting an Antenna ...................................................................................... 6
Connecting the Microphone ................................................................................ 7
Connecting an External Speaker ........................................................................ 8
Using Vehicle Battery Power .............................................................................. 8
Using the Transceiver as a Base Station ............................................................ 9
Operation ............................................................................................................... 10
Receiving Transmissions and Adjusting Squelch ............................................. 10
Transmitting ...................................................................................................... 11
Selecting the Emergency Channel ................................................................... 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
Troubleshooting .................................................................................................... 15
Reducing Noise ................................................................................................ 16
Care and Maintenance .......................................................................................... 17
Replacing the Fuse ........................................................................................... 18
Specifications ........................................................................................................ 19
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INSTALLATION
ATTACHING THE
MICROPHONE HOLDER
You can attach the microphone holder to
either side of the transceiver or to anoth-
er location in your vehicle.
To attach the holder to either side of the
transceiver, secure the holder to the
side using the supplied screws, wash-
ers, and lock washers.
To attach the holder to another location
in the vehicle, such as the dashboard,
follow these steps.
1. Using the holder as a template,
mark the positions for the mounting
screw holes at the desired location.
2. At each marked position, drill a hole
slightly smaller than the supplied
mounting screws.
Caution: Be careful not to drill into
anything behind the mounting sur-
face.
3. Attach the holder at the mounting
location using the supplied 3 mm
machine screws, spring washers,
plain washers, and nuts.
Note: If you cannot reach behind
the mounting surface to attach the
nuts on the machine screws, use the
supplied 3 mm plain washers and
self-tapping screws.
MOUNTING THE
TRANSCEIVER
The most common mounting location for
this CB is under a vehicle’s dashboard.
However, if you plan to use the TRC-
503 as a base station, you can place it
on a desk, shelf, or table (see “Using the
Transceiver as a Base Station” on
Page 9.
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 or other moving
parts.
• The CB is not directly in front of
heating vents.
• All wires and cables can reach their
connection points.
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Cautions:
• If you use the CB in a vehicle, mount
it securely to avoid damage to the
CB or vehicle or injury to anyone in
the vehicle during sudden starts or
stops.
• Do not mount the CB where it could
damage or interfere with the opera-
tion of any passive restraint safety
device (an airbag or seat belt).
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 supplied
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 supplied 6 mm
bolts, spring washers, plain wash-
ers, and nuts.
Note: If you cannot reach behind
the mounting surface to attach the
nuts on the bolts, use the supplied 6
mm bolts and plain washers to
secure the bracket.
4. Attach the CB to the mounting
bracket using the supplied rubber
washers and mounting knobs.
CONNECTING AN
ANTENNA
There are many different types of CB
antennas for mobile CBs. Each type has
its own benefits, so choose the one that
best meets your needs. Your local Ra-
dioShack store sells a wide variety of
antennas.
Note: If you are using this CB as a base
station, see “Using the Transceiver as a
Base Station” on Page 9.
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When you choose an antenna, keep in
mind that, for the best performance, you
should mount the antenna:
• as high as possible on the vehicle
• as far as possible from sources of
electrical noise
•vertically
Once you choose an antenna, follow its
mounting instructions. Then route the
cable to the transceiver and connect the
cable to the ANTENNA jack on the back
of the transceiver.
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 the
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 (not supplied).
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 tab on the side of the sup-
plied microphone’s plug and insert
the plug into the MIC jack on the
front of the transceiver. Be sure the
tab is aligned with the jack’s notch.
2. Slide the microphone onto the
microphone holder.
To disconnect the microphone from the
transceiver, press the tab on the side of
the plug. Then pull out the plug.
Caution: Never pull on the microphone
cable.
Tab Notch
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CONNECTING AN
EXTERNAL SPEAKER
You can connect your transceiver to an
external CB speaker, so you can hear
an incoming call when you are outside
your vehicle.
The external speaker you use with the
transceiver should have an impedance
of 8 ohms and be able to handle 3 to 10
watts of power. The speaker cable must
have a 1/8-inch (3.5-mm) plug. Your local
RadioShack store carries a variety of
speakers and cables to meet your
needs.
To connect the external speaker to the
transceiver, insert the speaker cable’s
plug into the EXT SPEAKER jack on the
back of the CB.
Note: When you connect an external
speaker, the CB’s internal speaker dis-
connects.
USINGVEHICLE BATTERY
POWER
Follow these steps to connect the trans-
ceiver to vehicle battery power.
1. Connect the red wire (with the in-
line fuse holder) on the back of the
transceiver to a point in your vehi-
cle’s fuse block that has power only
when the ignition is in the ACC
(accessory) 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.
To an 8-ohm,
3- to 10-Watt
Speaker
Black Wire
to Ground
Red Wire to
Switched
Accessory
Terminal
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USINGTHETRANSCEIVER
AS A BASE STATION
Although this transceiver 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 13.8-volt DC power supply that
can supply at least 1.5 amps
Caution: Most 13.8-volt DC power
supplies plug into a standard AC
outlet to produce DC power. Before
connecting your CB to a 13.8-volt
DC power supply, read and follow
the instructions included with the
power supply.
• base station antenna (such as Cat.
No. 21-989)
• coaxial antenna cable and connec-
tor (available at your local Ra-
dioShack 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 a power
line, contact with the antenna, mast, ca-
ble, or guy wires can cause electrocu-
tion and death. Call the power company
to remove the antenna. Do not attempt
to do so yourself!
Follow these steps to install the CB as a
base station.
Mount the base station antenna as de-
scribed in its owner’s manual.
1. Connect the antenna to the
ANTENNA jack on the back of the
CB.
2. Connect the transceiver’s black
power wire to the negative (–) termi-
nal on the DC power supply.
3. Connect the transceiver’s red wire
(with the in-line fuse) to the positive
(+) terminal on the DC power supply.
4. Connect the DC power supply to a
standard AC outlet.
Caution: To prevent damage to the CB,
be sure you connect both an antenna
and the microphone before you use the
CB.
Black Wire
to Negative
Terminal of
DC Power
Supply
Red Wire
to Positive
Terminal of
Supply
DC Power
Antenna
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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 your CB.
RECEIVING
TRANSMISSIONS AND
ADJUSTING SQUELCH
1. Turn SQUELCH fully counterclock-
wise.
2. Turn on the transceiver by turning
VOLUME clockwise until it clicks. The
channel display lights and the chan-
nel appears, and the RX indicator
lights.
3. Set OUT CH9 CH19 to OUT to select
a channel other than an emergency
channel.
4. Rotate the channel selector until the
display shows the desired channel.
5. Adjust VOLUME to a comfortable lis-
tening level.
6. To cut out background noise be-
tween 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 (those not strong enough
to break through a higher squelch
setting).
7. To turn off the CB, turn VOLUME
counterclockwise until you hear it
click. The display and indicators turn
off.
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