Radio Shack TRC-504 User manual

Cat. No. 21-1704
OWNER’S MANUAL
Please read before using this equipment.
TRC-504
40-Channel Mobile CB Radio
with On-Mic Channel Selector
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2
FEATURES
©1998 Tandy Corporation.
All Rights Reserved.
RadioShack and Powerhorn are registered trademarks used by Tandy Corporation.
Your RadioShack TRC-504 Compact
40-Channel Mobile CB Radio is a break-
through in CB design technology. You
can mount it in a vehicle for mobile use,
or in your home for use as a base sta-
tion.
Your CB has these advanced features:
Dual Channel Controls — let you tune
the channel from the transceiver or the
handset.
RF Gain Control — lets you adjust the
receiver’s gain to match the strength of
the signal.
Emer
g
enc
y
Channel Switch — lets
you quickly switch to Channel 9 or 19 so
you can monitor or report emergency sit-
uations.
Two-Di
g
it Channel Displa
y
with TX
(Transmit) and RX (Receive) Indica-
tors — lets you see the CB’s operating
status at a glance.
External Speaker Jack — lets you con-
nect your CB to an external speaker.
Built-In PA (Public Address) Amplifier
— lets you use your CB as a public ad-
dress system when you add an optional
PA speaker.
Backlit Controls — help you easily find
the right control when you use the CB at
night.
Phase-Locked Loop (PLL) Frequenc
y
S
y
nthesizer — 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.
Automatic Noise Limiter — reduces
impulse-type noises while receiving.
Universal Mountin
g
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 _________________
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3
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
radio is causing the interference, turn off
your CB radio. If the interference goes
away, your CB radio is causing it. Try to
eliminate the interference by:
• moving your CB radio away from the
receiver
• contacting your local RadioShack
store for help
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
Attaching the Microphone Holder ....................................................................... 5
Mounting the Transceiver ................................................................................... 5
Connecting an Antenna ...................................................................................... 6
Connecting the Microphone ................................................................................ 7
External Speaker ................................................................................................ 8
Connecting a CB Speaker ........................................................................... 8
Connecting a PA Speaker ............................................................................ 8
Using Vehicle Battery Power .............................................................................. 9
Using the Transceiver as a Base Station ............................................................ 9
Operation ............................................................................................................... 11
Receiving Transmissions and Adjusting Squelch ............................................. 11
Transmitting ...................................................................................................... 12
Selecting the Emergency Channel ................................................................... 12
Using the PA Amplifier ...................................................................................... 12
Using the Monitor Feature ................................................................................ 13
Operational Hints .................................................................................................. 14
Common Uses for a CB .................................................................................... 14
Personal Uses ............................................................................................ 14
Business Uses ........................................................................................... 14
Transmission Courtesy ..................................................................................... 14
Using Common 10-Codes ................................................................................ 15
Maximum Range .............................................................................................. 16
Troubleshootin
g
.................................................................................................... 17
Reducing Noise ................................................................................................ 19
Care and Maintenance .......................................................................................... 20
Replacing the Fuse ........................................................................................... 21
Specifications ........................................................................................................ 22
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5
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 the transceiver,
secure the holder to either side using
the supplied 3 mm screws 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 machine
screws, spring washers, plain wash-
ers, 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-
504 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 any-
one 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 5 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 5
mm self-tapping screws 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. Align the tab on the side of the sup-
plied microphone’s plug with the
notch in the microphone jack (on the
side of the transceiver). Then insert
the plug into the jack.
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.
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8
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, or use the CB as a PA sys-
tem.
Connecting a CB Speaker
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 (such as RadioShack
Cat. No. 21-549). The speaker cable
must have a 1/8-inch plug.
To connect the external speaker to the
transceiver, insert the speaker cable’s
plug into EXT SPEAKER on the back of
the CB.
Note: When you connect an external
speaker, the CB’s internal speaker dis-
connects.
Connecting a PA Speaker
The PA speaker should:
• have an impedance of 8 ohms
• be able to handle at least 5 watts of
power (the RadioShack Power-
horn®series speakers meet this
requirement)
• have a cable with a 1/8-inch plug
If your PA speaker meets the other
specifications but does not already have
a 1/8-inch plug, you can connect it using
a phono plug-to-wire cable, available at
your local RadioShack store.
To connect the PA speaker to the trans-
ceiver, insert the speaker cable’s plug
into
PA SPEAKER on the back of the CB.
Note: To avoid acoustic feedback, the
speaker should be at least 6 feet from
the CB. If you experience feedback,
avoid keying the microphone until you
have moved the speaker away from the
CB.
To External
Speaker
To External
PA Speaker
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9
USING VEHICLE 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.
USING THE
TRANSCEIVER 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:
• 12-volt DC power supply that can
supply at least 2 amps (such as Cat.
No. 22-504)
Caution: Most 12-volt DC power
supplies plug into a standard AC
outlet to produce DC power. Before
connecting your CB to a 12-volt 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-
tors, available at your local
RadioShack store
Black Wire
to Ground
Red Wire to
Switched
Accessory
Terminal
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Caution: To prevent damage to the CB,
be sure you connect an antenna and the
microphone before you use the CB.
Follow these steps to install the CB as a
base station.
1. Mount the base station antenna as
described in its owner’s manual.
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, cable, or guy
wires can cause electrocution and
death. Call the power company to
remove the antenna. Do not attempt
to do so yourself!
2. Connect the antenna to ANTENNA
on the back of the CB.
3. Connect the transceiver’s black
power wire to the negative (–) termi-
nal on the DC power supply.
4. Connect the transceiver’s red wire
(with the in-line fuse) to the positive
(+) terminal on the DC power sup-
ply.
5. Connect the DC power supply to a
standard AC outlet.
Black Wire
to Negative
Terminal of
DC Power
Supply
Red Wire
to Positive
Terminal of
Supply
DC Power
Antenna
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