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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4
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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6
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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7
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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10
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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11
OPERATION
Before you use your CB, you should
know how to use it effectively and cour-
teously. “Operational Hints” on Page 14
contains information that will help you
get more enjoyment from your CB.
RECEIVING
TRANSMISSIONS AND
ADJUSTING SQUELCH
1. Set PA/MON/CB to CB.
2. Turn SQUELCH fully counterclock-
wise.
3. Turn
RF GAIN fully clockwise.
4. Turn on the transceiver by turning
VOLUME clockwise until it clicks.
The channel display lights, the
channel appears, and the RX indica-
tor lights.
5. Set OUT/CH9/CH19 to OUT to select
a channel other than an emergency
channel.
6. Rotate the channel selector, or
repeatedly press (or hold down) UP
or DOWN on the microphone until
the display shows the desired chan-
nel.
7. Adjust VOLUME to a comfortable lis-
tening level.
8. To cut out background noise
between transmissions, wait until
there is no signal, then slowly turn
SQUELCH clockwise until the back-
ground noise stops.
Notes:
• To receive very weak signals, turn
SQUELCH counterclockwise. You
hear noise between transmis-
sions, but you also hear weak
transmissions (those not strong
enough to break through a higher
squelch setting).
• If you experience interference
from nearby frequencies, turn RF
GAIN counterclockwise to reduce
the receiver’s sensitivity.
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12
9. To turn off the CB, turn VOLUME
counterclockwise until you hear it
click. The display and indicators turn
off.
TRANSMITTING
Note: We recommend you try receiving
before you transmit.
1. Follow Steps 1–8 in “Receiving
Transmissions and Adjusting
Squelch.”
2. To transmit, hold down PUSH TO
TALK on the microphone. The TX
indicator lights. Hold the micro-
phone 2–3 inches from your mouth
and speak in a normal tone of voice,
then release PUSH TO TALK when
you finish. The TX indicator turns off.
3. To turn off the CB, turn VOLUME
counterclockwise until you hear it
click. The display and RX indicators
turn off.
SELECTING THE
EMERGENCY CHANNEL
Im
p
ortant: Channel 9 and Channel 19
are reserved for motorist assistance and
for reporting emergency information
about accidents, hazardous road condi-
tions, and so on. Always give emergen-
cy messages priority on Channel 9 or
Channel 19.
To select the emergency Channel 9 or
Channel 19, set OUT/CH9/CH19 to CH9
or CH19. The selected channel number
(9or 19) flashes on the display and the
transceiver stays on the channel you se-
lected.
Note: You can also select Channel 9 or
19 using the channel selector or UP or
DOWN when OUT/CH9/CH19 is set to
OUT.
To select another channel, set OUT/CH9/
CH19 to OUT. The previously selected
channel number appears on the display.
USING THE PA AMPLIFIER
Your CB has a built-in PA (public ad-
dress) amplifier. With an optional PA
speaker (see “Connecting a PA Speak-
er” on Page 8), you can turn your radio
into a mobile public address system.
PUSH
TO
TALK
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13
Follow these steps to use the PA ampli-
fier.
1. Turn on the transceiver. Then set
PA/MON/CB to PA. PA appears on
the display.
2. To transmit, press PUSH TO TALK on
the microphone. Hold the micro-
phone 2–3 inches from your mouth
and speak in a normal tone of voice.
3. Turn VOLUME for the desired vol-
ume level. If you hear a high-pitched
squeal, turn VOLUME counterclock-
wise until the squeal stops.
Note: To avoid acoustic feedback,
the speaker should be at least 6 feet
from the CB. If you experience feed-
back, avoid keying the microphone
until you have moved the speaker
away from the CB.
4. To turn off the PA amplifier, turn the
transceiver off. Or, set PA/MON/CB
to
CB for CB communication.
USING THE MONITOR
FEATURE
You can use your CB as a receiver to
listen to transmissions on an optional PA
speaker. With an optional PA speaker
connected, set PA/MON/CB to MON.
When PA/MON/CB is set to MON, your
CB cannot transmit and you hear sound
only from the external PA speaker.
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14
OPERATIONAL HINTS
Like most activities, CB radio has its
customs and courtesies. The following
tips will help you get the most enjoyment
from your CB.
COMMON USES
FOR A CB
Personal Uses
• Keep in touch with home while driv-
ing to work, to the store, or to a
social activity. Let your family know
you are tied up in traffic or that you
will stop by the store on the way
home.
• If you are a two-car (or more) family,
CB radios are great for communicat-
ing with family members while they
are in their cars.
• Contact friends or neighbors — find
out “what’s happening” or plan a
get-together.
• Ever have car trouble or run out of
gas on the highway? What an
assurance it is to be able to radio for
assistance!
• Camping, fishing, and other sports
are more fun with a CB radio.
Locate a buddy or find out “what’s
cooking” back at camp.
Business Uses
• For security officers, a CB is more
than a convenience — it is a must
for both safety and efficiency.
• Truck drivers and delivery personnel
can learn road and traffic conditions
and get assistance in locating desti-
nations. A CB radio is also good
company on those “long hauls.”
• On construction crews, a CB radio
quickly pays for itself when you are
calling for additional materials or
coordinating the activities of differ-
ent work crews.
TRANSMISSION
COURTESY
Please follow these guidelines of radio
courtesy when using your CB.
• Wait for a pause in someone else’s
transmission before you ask for a
break.
• If you do not receive an answer to
your call after a second attempt,
sign off and wait several minutes
before trying again.
• Do not hold down PUSH TO TALK
when you are not talking. (This is
called
dead keying
.)
• Assist callers with directions, infor-
mation about road conditions, and
any other reasonable requests.
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15
USING COMMON 10-
CODES
Citizen’s band operators and CB radio
users have largely adopted the 10-
codes for standard questions and an-
swers. These codes permit faster com-
munication and better intelligibility in
noisy areas.
This table lists codes adopted by the As-
sociated Public Safety Communications
Officers (APCO).
Note: Although this table lists most of
the 10-codes' meanings in the form of a
statement, they can also be phrased as
questions (10-6: Are you busy?, 10-20:
What is your location?).
Code Meaning
10-1 Your si
g
nal is bad.
10-2 Your si
g
nal is
g
ood.
10-3 Stop transmittin
g
.
10-4 Messa
g
e received and under-
stood.
10-5 Relay information to _____.
10-6 I am busy or are you busy?
10-7 Out of service.
10-8 In service.
10-9 Repeat last messa
g
e.
10-10 Ne
g
ative (NO).
10-11 _____ in service.
10-12 Stand by.
10-13 Report road/weather condi-
tions.
10-14 Information.
10-15 Messa
g
e delivered.
10-16 Reply to messa
g
e.
10-17 En route.
10-18 Ur
g
ent.
10-19 Contact _____.
10-20 What is your location?
10-21 Call _____ by telephone.
10-22 Cancel last messa
g
e.
10-23 Arrived at the scene.
10-24 Assi
g
nment complete.
10-25 Meet _____.
10-26 Estimated time of arrival is
_____.
10-30 Use caution.
10-31 Pick up.
10-33 Emer
g
ency traffic. Clear the
channel.
10-34 What time is it?
10-41 Switch to Channel xx.
10-62 Cannot understand.
Code Meaning
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16
MAXIMUM RANGE
The maximum range and quality of CB
radio transmissions vary depending on
the following conditions:
• The type and quality of antenna
used
• The height of the antenna’s mount-
ing location — the higher the
antenna, the better the signal’s
range
• The surrounding terrain — moun-
tains and tall buildings limit the
range
• Weather conditions
• The number of nearby radios oper-
ating on the same channel
• Standing wave ratio (SWR) between
the antenna and the CB.
Note: Your CB radio’s transmission
range is generally line-of-sight.
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17
TROUBLESHOOTING
If your CB is not working as it should, follow these suggestions to see if you can elim-
inate the problem. If you cannot, take the CB to your local RadioShack store for as-
sistance.
Symptom Check/Try
CB has trouble receiving. Turn transceiver power on.
Microphone connected? Secure connections.
Antenna connected? Secure connections.
Too much squelch? Adjust as needed.
Radio not on operating channel? Switch to active
channel.
Be sure PA/MON/CB is set to CB.
Adjust VOLUME.
Adjust RF GAIN.
CB has trouble transmit-
ting. Turn transceiver power on.
Antenna connected? Secure connections.
All connections free of corrosion? Clean and tighten.
Microphone connector loose? Firmly press micro-
phone connector into jack.
Microphone connected? Secure connections.
Be sure PA/MON/CB is set to CB.
Radio not on operating channel? Switch to an active
channel.
PUSH TO TALK fully pressed? Press completely.
CB does not work at all. Power connected? Secure connections.
Microphone connected? Secure connections.
Fuse needs replacing? Replace with identical fuse.
See “Replacing the Fuse” on Page 21.
Cannot select a channel. Be sure PA/MON/CB is set to CB.
PUSH TO TALK pressed? Release PUSH TO TALK.
Set OUT/CH9/CH19 to OUT.
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18
PA does not work. Connect a PA speaker. Secure connections.
Be sure PA/MON/CB is set o PA.
Adjust VOLUME.
Sound is distorted. Adjust RF GAIN.
Adjust VOLUME.
Symptom Check/Try
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19
REDUCING NOISE
Because your CB is exceptionally quiet,
any noise you hear is probably from an
external source in your vehicle such as
the alternator, another radio or spark
plugs.
The transceiver uses an ANL (Automatic
Noise Limiter) circuit to reduce noise.
However, if possible, try to eliminate the
noise by finding its source.
You can determine the noise’s source
by turning off the engine and operating
the CB with your vehicle’s ignition set to
ACC. If the noise is reduced, the prob-
lem is in your vehicle’s ignition or electri-
cal system.
Here are a few hints to help you reduce
or eliminate such noise:
• Make all CB power and antenna
wires as short as possible.
• Route the power wires away from
the antenna wires.
• Be sure that the chassis ground
connection is secure.
• Replace old ignition wires with new,
high-voltage, noise suppression
wires.
• Install noise suppressors on your
spark plugs, or install new spark
plugs that have built-in noise sup-
pressors.
• If problems persist, check your alter-
nator/generator and regulator
gauges. You can reduce the noise
from these sources by using bypass
capacitors at the various output volt-
age points.
Your local RadioShack store has a wide
selection of noise suppression accesso-
ries.
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20
CARE AND MAINTENANCE
Your RadioShack TRC-504 40-Channel Mobile CB Radio is an example of superior
design and craftsmanship. The following suggestions will help you care for your CB
so you can enjoy it for years.
Keep the CB dry. If it gets wet, wipe it dry immediately. Liquids can con-
tain minerals that can corrode electronic circuits.
Handle the CB gently and carefully. Dropping it can damage circuit
boards and cases and can cause the CB to work improperly.
Use and store the CB in normal temperature environments. Tempera-
ture extremes can shorten the life of electronic devices and distort or
melt plastic parts.
Keep the CB away from dust and dirt, which can cause premature wear
of parts.
Wipe the CB with a damp cloth occasionally to keep it looking new. Do
not use harsh chemicals, cleaning solvents, or strong detergents to
clean the CB.
Modifying or tampering with the CB’s internal components can cause a malfunction
and might invalidate its warranty and void your FCC authorization to operate it. If your
CB is not performing as it should, take it to your local RadioShack store for assis-
tance.
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