21-1574.fm Page 1 Thursday, May 13, 1999 4:03 PM
Cat. No. 21-1574
OWNER’S MANUAL
Please read before using this equipment.
TRC-446
Deluxe 4 Watt 40-Channel
Mobile CB Radio
with Weather Alert and ACE
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Noise Blanking — reduces the noise
occasionally generated by nearby elec-
trical motors or automotive ignition sys-
tems.
FCC INFORMATION
The Federal Communications Commis-
sion (FCC) does not require you to have
a license to operate this CB. 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 regu-
lations with your CB.
CB/WX/PA Switch — lets you quickly
select among normal CB operation,
weather mode, or public address mode.
RX/TX Indicator — shows whether the
CB is transmitting or receiving.
Warning: Do not open your CB to make
any internal adjustments. Any internal
adjustments can be made only by an au-
thorized service technician.
S/RF/SWR/CAL Switch — lets you
quickly change the display of the RF/
Signal Meter to show radio input/output
signal strength, the standing wave ratio
of the antenna, or SWR calibration data.
Unauthorized internal adjustments and/
or modifications can lead to illegal oper-
ation as defined by Part 95 of FCC
Rules. Such illegal operation can lead to
very serious consequences. To be safe
and sure:
Universal Mounting Bracket — lets
you mount your CB securely in your ve-
hicle.
Note: To use this CB, you need a mo-
bile or base station antenna (not sup-
plied). Your local RadioShack store has
a wide variety of antennas. For more in-
formation, see “Installing an Antenna”
on Page 7.
• Never open your CB's case.
• Never modify your CB.
Your CB might cause TV or radio inter-
ference even when it is operating prop-
erly. 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 either moving your CB
away from the receiver or contacting
your local RadioShack store for help. If
you cannot eliminate the interference,
the FCC requires that you stop using
your CB.
We recommend you record your CB's
serial number here. The number is on
the CB's back panel.
Serial Number__________________
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CONTENTS
Installation ............................................................................................................... 5
Mounting the TRC-446 ....................................................................................... 5
Connecting the Microphone ................................................................................ 6
Installing an Antenna .......................................................................................... 7
Selecting an Antenna ................................................................................... 7
Connecting an Antenna ............................................................................... 7
Using Vehicle Battery Power .............................................................................. 7
Using the CB as a Base Station ......................................................................... 8
Connecting Optional External Speakers ............................................................. 8
External CB Speaker ................................................................................... 8
Public Address Speaker ............................................................................... 9
Adjusting the Standing Wave Ratio .................................................................... 9
Standing Wave Ratio Guidelines ...................................................................... 10
Standing Wave Ratio Performance ............................................................ 10
A Quick Look at the Controls ............................................................................... 11
Operation ............................................................................................................... 12
Changing Channels Using the Controls on the Microphone ............................. 13
Listening to Weather Broadcasts ...................................................................... 13
Weather Alert .................................................................................................... 14
Using the Public Address Function ................................................................... 14
CB Operation Tips ................................................................................................ 15
Business Uses .................................................................................................. 15
Personal Uses .................................................................................................. 15
CB Courtesy ..................................................................................................... 15
Using Common 10-Codes .................................................................................... 16
Maximum Range .............................................................................................. 17
Troubleshooting .................................................................................................... 18
Care and Maintenance .......................................................................................... 19
Specifications ........................................................................................................ 21
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INSTALLATION
N
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-44
-9
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MIC
6
T
X
S/RF
/R
X
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F
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X
A
/A
CB
IN
L
VOLU
E
R
CH-19
T
ME
W
NB
E
A
CAL
SQUELCH
T
H
ACE
E
R
PA
OFF
CAL
SWR
TRC-446
OFF
TX/RX
RF GA
WX/ALERT
IN
WEATHER
• the CB is not directly in front of heat-
ing vents
MOUNTING THE
MICROPHONE HOLDER
Cautions:
Using a Philips screwdriver and the sup-
plied screw and washers, attach the
supplied microphone holder to the CB's
left or right side, either horizontally or
vertically (depending on how you plan to
use it).
• If you use the TRC-446 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 proper
operation of any passive restraint
safety device (an air bag or seat
belt).
MOUNTING THE TRC-446
The most common mounting location for
this CB is under a vehicle’s dashboard.
If you use the TRC-446 as a base sta-
tion, you can place it on a desk, shelf, or
table (See “Using the CB as a Base Sta-
tion” on Page 8).
Follow these steps to mount the CB us-
ing the supplied hardware.
1. Select a location that provides
secure mounting.
When mounting the CB in a vehicle,
choose a location where:
Caution: Be careful not to drill into
anything behind the mounting sur-
face.
• you can easily reach the CB
2. Using the slots in the mounting
bracket as a template, mark the
positions for the screw holes.
• wires and cables are routed away
from the vehicle's pedals or other
moving parts
3. In each marked location, drill a hole
slightly smaller than the supplied
• all wires and cables can reach their
connection points
mounting screws.
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4. Using a Phillips screwdriver, attach
the mounting bracket to the mount-
ing surface with the supplied large
mounting screw and star lock wash-
ers.
inside the MIC jack, then fully insert
the plug into the jack.
2. Secure the plug by turning the plug's
locking nut clockwise.
3. Slide the microphone onto the
microphone holder.
5. Attach the CB to the mounting
bracket using the supplied rubber
washers and mounting knobs.
To disconnect the microphone, unscrew
the locking nut and gently pull out the
microphone plug.
CONNECTING THE
MICROPHONE
Caution: Always grasp the connector
body when you are disconnecting the
microphone. Never pull on the micro-
phone cable.
1. Align the slot on the top of the
microphone plug with the ridge
EXT SP
PA SP
POWER
13.8V DC
+
-
ANTENNA
PSP EXT SP
ANTENNA
13.8 DC Power Supply
POWER
-
+
13.8V DC
R
CAT NO.: 21-1574 TRC-446 FCC ID: AAO21-1574
CUSTOM MANUFACTURED IN THAILAND FOR RADIOSHACK,
A
DIVISION OF TANDY CORPORATION
FORT WORTH, TEXAS 76102
0000001
SERIAL NO.:
Base Station Power Setup
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• Do not run the cable through a vehi-
cle's engine compartment or other
areas that produce extreme heat.
INSTALLING AN
ANTENNA
Caution: To prevent damage to your
CB, do not attempt to transmit without
an antenna attached.
USING VEHICLE
BATTERY POWER
Selecting an Antenna
You can power this CB from your vehi-
cle's battery or from standard AC power
with an optional DC power supply. For in-
formation on using AC power, see “Using
the CB as a Base Station” on Page 8.
When you decide on an antenna and its
location, consider these points:
• The antenna should be positioned
as high as possible.
Follow these steps to power the CB from
your vehicle's battery.
• The antenna and the antenna cable
should be routed as far as possible
from any source of electrical noise
such as ignition systems, electric
gauges, and motors.
1. Plug the single-connector end of the
power cord into POWER 13.8V DC
on the CB's back panel.
Your local RadioShack store sells a vari-
ety of CB antennas for both mobile and
base-station use. Choose the one that
best meets your needs.
2. Connect the black wire to your vehi-
cle’s negative (–) battery terminal or
to a metal part of the vehicle's frame
that is not insulated from the frame
by a plastic part.
Connecting an Antenna
3. Connect the red wire, with its in-line
fuse, to a source of voltage that
turns on and off with the ignition
switch, such as a spare accessory
terminal in your vehicle's fuse box.
This assures you that power to the
CB is turned off when you turn off
the ignition.
Follow the mounting instructions sup-
plied with the antenna you choose.
Route the antenna cable to the CB, then
thread the PL-259 antenna cable plug
into ANTENNA on the back of the CB.
Cautions:
4. Connect the orange wire, with its in-
line fuse, to a source of voltage that
supplies constant positive (+) power
(regardless of the ignition switches
position) or directly to your vehicle's
positive (+) battery terminal. This
enables the radio to “remember” the
last channel you tuned to when you
turn the radio back on.
• Do not run the cable over sharp
edges or moving parts that might
damage it.
• Do not run the cable next to power
cables or other CB antenna cables.
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3. Plug the single connector end of the
power cord into POWER 13.8V DC
on the CB's back panel.
USING THE CB AS A
BASE STATION
Although this CB is designed for mobile
use, you can also use it as a base sta-
tion. For base-station installation, you
need a regulated 12-volt DC power sup-
ply, such as Cat. No. 22-504 available at
your local RadioShack store.
4. Connect the black wire to the DC
power supply's negative (–) termi-
nal.
5. Connect the red wire and orange
wires, with in-line fuses, to the DC
power supply's positive (+) terminal.
Caution: Most 12-volt DC power sup-
plies 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.
Note: Due to the lack of a constant
12VDC, as in an automotive installation,
if you turn off the DC power supply, the
CB “remembers” the last channel you
tuned for only a few minutes. When you
turn on the CB and the DC power supply
again, the radio automatically tunes to
Channel 9.
You also need a base station antenna
and coaxial antenna cable and connec-
tors. Your local RadioShack store also
carries a wide selection of suitable an-
tennas, cables, and connectors.
CONNECTING OPTIONAL
EXTERNAL SPEAKERS
Follow these steps to install the CB as a
base station.
You can connect an external CB or PA
speaker to your CB. The larger, external
speaker provides greater clarity. A PA
speaker lets you take advantage of the
amplifier and mic to use the CB as a
public-address system.
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 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.
External CB Speaker
To connect an external CB speaker,
use a speaker rated at 8-ohms and ca-
pable of handling 3–10 watts of power
(such as Cat. No. 21-549). Simply plug
1
the speaker cable's /8-inch plug into
EXT SP. Connecting the external speak-
er automatically disconnects the inter-
nal speaker.
2. Route the antenna cable to the CB,
then
connect
the
cable
to
ANTENNA on the back of the CB.
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points to CAL on the upper SWR
scale.
Public Address Speaker
To connect a PA speaker to the CB, use
an 8-ohm speaker capable of handling 5
or more watts of power and equipped
4. Release the microphone's talk but-
ton.
1
with an /8-inch connector on the cable.
5. Set S/RF/SWR/CAL to SWR.
Contact your local RadioShack store
for a selection of suitable speakers.
Plug into PA SP. See “Using the Public
Address Function” on Page 14 for oper-
ation instructions.
6. Press the microphone's talk button
again and note the actual SWR
measurement on the upper SWR
scale. See the chart on Page 10 for
help in interpreting the SWR meter
readings.
ADJUSTING THE
STANDING WAVE RATIO
The SWR value takes into account the
actual frequency of the RF signal trans-
mitted. Therefore, you will get a different
SWR reading from one CB channel to
another. Almost all the CB transmis-
sions usually fall within an acceptable
range. However, for optimum radio per-
formance, we recommend that you fine
tune the antenna's system based on the
channel you use most. If you have no
particular channel preference, set your
antenna's SWR for maximum perfor-
mance on Channel 19.
Most antennas are factory adjusted.
However, you can usually improve per-
formance by matching the characteris-
tics of your antenna system to the CB's
RF output power using the built-in SWR
meter. The impedance of a CB’s output
compared to the impedance of the an-
tenna and the antenna cable is typically
slightly mismatched. By adjusting this
impedance ratio to be as close to 1:1 as
possible, you maximize the efficiency of
your system.
After you have properly installed the an-
tenna and routed its cable, follow these
steps to adjust the standing wave ratio
Note: The SWR on some mobile and
base-station antennas cannot be
changed.
1. Turn on the CB by turning OFF/VOL-
UME clockwise until it clicks.
2. Set S/RF/SWR/CAL to CAL.
3. Hold down the microphone's talk
button and adjust SWR CAL so the
SWR/RF signal meter's needle
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STANDING WAVE RATIO GUIDELINES
The ideal standing wave ratio (SWR) is 1:1, or a meter reading of 1 on the SWR
meter's top scale. This reading, however, can only be obtained under laboratory con-
ditions. A SWR ratio of 1.5:1 to 2:1 is excellent for most mobile CB antenna applica-
tions. This chart helps you interpret the different readings you might see.
Standing Wave Ratio Performance
Ratio
Rating
Evaluation
1:1 – 1.5:1
Superior
Perfect match between the an-
tenna/cable and the RF output of
the CB.
1.5:1 – 2:1
2:1 – 3:1
Excellent
The antenna/cable system is an
outstanding match to the trans-
mitter’s RF output. Ideal for most
CB installations.
Good
The antenna/cable system will
perform to specification under
most normal conditions.
Higher than
3.1:1
Inefficient
Indicates a need to inspect the
system, the mounting of the
antenna and all pertinent hard-
ware.
Prolonged exposure to salt spray, humidity, weather-induced corrosion, or vehicle vi-
bration can cause antenna performance to degrade with a subsequent rise in the
SWR. Anytime you notice that the SWR reading is greater than 3:1, check the condi-
tion of the antenna, the antenna cable and all antenna connectors and hardware.
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A QUICK LOOK AT THE CONTROLS
Channel Display
CB/Weather Alert/Pub-
lic Address Switch
Channel 9-NOR-
Channel 19 Switch
RF Meter/SWR/
Calibrate Switch
Noise Blanking On/Off
Switch
Weather Alert
Indicator
Audio Clarity
Enhancer On/Off
Switch
SWR Meter
RF Meter
Transmit/Receive
Indicator
Hand-Held MIC with
Channel Up/Down
Control
Squelch
Control
Rotary Channel
Tuning Dial
RF Gain
Control
Volume /
Power Switch
NOAA
Weather
Channel
Selector
Standing Wave Ratio
Calibration Control
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OPERATION
Before you start using your CB, you
should know how to use it effectively
and courteously. “CB Operation Tips” on
Page 15 contains information that will
help you get more enjoyment from using
your CB.
6. To manually tune channels, turn the
tuning control beneath the display to
select a channel. The selected
channel number appears, and the
SWR/RF/Signal Meter shows the
signal strength.
To quickly tune to Channel 9 or 19,
set CH-9/NOR/CH-19 to CH-9 or CH-
19. 9 or 19 flashes.
TURNING ON THE CB AND
RECEIVING
TRANSMISSIONS
Important: Always give emergency
communications priority on Chan-
nels 9 and 19. Your CB provides for
fast selection of Channel 9 and 19
for that reason.
1. Turn SQUELCH fully counterclock-
wise.
2. Set CH-9/NOR/CH-19 to NOR, S/RF/
SWR/CAL to S/RF (send and
receive), and CB/WX/PA to CB.
Notes:
• Selecting either Channel 9 or 19
overrides the manual channel
selection control.
3. To turn on the CB, turn OFF/VOLUME
clockwise until it clicks and you hear
a hissing sound. TX/RX lights, the
CB displays the last-tuned channel
number, and the SWR/RF/Signal
Meter lights.
• All channels, with the exception of
Channels 9 and 19, by agree-
ment, are available for general
communications. Channels 9 and
19 are reserved for motorist
assistance and for reporting
emergency situations, hazardous
road conditions, and the like.
4. Turn SQUELCH clockwise until the
hissing sound stops.
Note: If the CB picks up unwanted,
partial or very weak transmissions,
continue to turn SQUELCH clockwise
to decrease the CB's sensitivity to
these signals. Turn SQUELCH coun-
terclockwise if you want to listen to a
weak or distant station.
7. If necessary, turn RF GAIN clockwise
to boost the strength of a signal.
8. If you hear low-level popping-type
noise, set NB/OFF to NB to turn on
the noise blanking circuit.
9. To improve communication quality,
set ACE/OFF to ACE. This enables
the ACE circuit.
5. Adjust OFF/VOLUME to a comfort-
able listening level.
10. To turn off the TRC-446, turn OFF/
VOLUME counterclockwise until you
hear it click.
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4. To turn off the TRC-446, turn OFF/
VOLUME counterclockwise until you
hear it click.
Changing Channels Using the
Controls on the Microphone
To tune to the next higher or lower chan-
nel, press UP or DOWN on the micro-
phone.
LISTENING TO
WEATHER BROADCASTS
To quickly change channels in either di-
rection, hold down UP or DOWN until you
reach the desired channel.
The TRC-446 can receive seven pre-
programmed weather channels which
have been allocated by the Federal
Communications Commission (FCC) for
use by the National Oceanographic and
Atmospheric Administration (NOAA).
NOAA broadcasts your local forecast
and regional weather information on one
or more of these channels in your area.
To prevent accidentally changing the
channel with UP or DOWN, press LOCK.
Press LOCK again to restore the UP or
DOWN operation.
TRANSMITTING
Your TRC-446 receives these weather
service frequencies:
Note: We recommend you try receiving
transmissions before you transmit.
Frequency
Channel
(MHz)
1. Follow Steps 1–9 under “Turning On
the CB and Receiving Transmis-
sions” on Page 12.
162.400
162.425
162.450
162.475
162.500
162.525
162.550
WX2
WX4
WX5
WX3
WX6
WX7
WX1
2. Hold down the microphone's talk
button and speak into the micro-
phone in a normal voice from about
2–3 inches away. TX/RX turns red,
and the SWR/RF/signal meter indi-
cates the strength of your transmis-
sion.
Note: Do not speak too loudly when
transmitting. It does not make your
signal any stronger, and might dis-
tort your transmission.
3. When you finish transmitting,
release the microphone talk button.
TX/RX turns green. The TRC-446
can now receive transmissions.
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To listen to one of the seven available
weather channels, set CB/WX/PA to WX,
then rotate WEATHER to choose a chan-
nel for your listening area. The channel
display and the SWR turn off. Readjust
OFF/VOLUME if necessary.
However, WX/ALERT turns off if you
turn to WX or move out of the range of
that NOAA channel. To turn off the indi-
cator you can also turn power off, then
on.
The orange indicator means switch to
WX to hear special severe weather in-
formation and warnings.
Note: When the CB radio is set to CB or
PA, and you enter a NOAA broadcast ar-
ea, the state of the WX/ALERT indicates
three possible situations:
USING THE PUBLIC
ADDRESS FUNCTION
OFF — No weather signal on the
selected weather channel. Check
another channel.
1. Connect a PA speaker to the TRC-
446 (see “Connecting Optional
External Speakers” on Page 8).
GREEN — Normal weather signal.
No emergecy broadcast.
ORANGE — Weather alert broad-
cast on the selected channel. Turn
to WX to listen to information or
power off then on to clear the alert.
2. Turn OFF/VOLUME fully counter-
clockwise.
3. Set CB/WX/PA to PA. The meter and
TX/RX turn off.
4. Hold down the microphone talk but-
ton and speak into the microphone
in a normal voice. Be sure the
microphone is as far from the PA
speaker as possible to reduce the
possibility of audio feedback or
howl.
Weather Alert
In the event of severe weather condi-
tions, the National Weather Service
broadcasts a special 1050 Hz tone. The
TRC-446 sounds this tone if it is turned
on and CB/WX/PA is set to CB or WX.
The tone does not sound if the radio is
set to PA. When the radio receives this
signal tone, WX/ALERT lights orange
regardless of the position of CB/WX/PA.
5. Adjust OFF/VOLUME as needed to
adjust the PA's volume.
NOAA transmits this tone for 5 to 10
seconds. If the TRC-446 is set to CB or
PA, the orange light remains on even af-
ter transmission ceases. You do not
have to be present when the signal is re-
ceived to be aware of an alert.
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CB OPERATION TIPS
Like most activities, CB radio users have
customs and courtesies. The following
tips will help you get the most enjoyment
out of your CB.
• 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? With your CB
you can have peace of mind know-
ing you can call for assistance.
TYPICAL USES
FOR A CB RADIO
• Camping, fishing, and other sports
are more fun with a CB. Keep in
touch with a buddy or find out
“what's cooking” back at camp.
Business Uses
• Truck drivers and delivery personnel
can learn road and traffic conditions
and get assistance in locating desti-
nations. A CB is also good company
on these “long hauls.”
CB Courtesy
• Wait for a pause in someone else's
transmission before you ask for a
break.
• Used by construction crews, a CB
quickly pays for itself when you are
calling for additional materials or
coordinating the activities of differ-
ent work crews.
• If you do not receive an answer to
your call after a second attempt,
sign off and wait several minutes
before trying again.
• For security officers, a CB is more
than a convenience — it is a must
for both safety and efficiency.
• Do not hold down the microphone
talk button, called “dead keying”,
when you are talking.
• Assist callers with directions, infor-
mation about road conditions, and
any other reasonable requests.
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-or-more car family,
CBs are great for inter-car communi-
cations while family members are
going places.
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USING COMMON 10-CODES
Citizen's band operators have largely
Code
Meaning
adopted the following 10-codes for stan-
dard questions and answers. These
codes permit faster and more precise
communication in noisy areas. This ta-
ble lists codes adopted by the Associat-
10-21
10-22
10-23
10-24
10-25
10-26
Call______by telephone.
Cancel last message.
Arrived at the scene.
Assignment complete.
Meet______________.
ed
Public-Safety
Communications
Officers (APCO).
Code
Meaning
Estimated time of arrival
is___
10-1
10-2
10-3
10-4
Your signal is bad.
Your signal is good.
10-30
10-31
10-33
Use caution.
Pick up.
Stop transmitting.
Emergency traffic. Clear the
channel.
Message received and under-
stood.
10-34
10-41
10-62
What time is it?
10-5
10-6
Relay information to ______.
I am busy or are you busy?
Out of service.
Switch to Channel –
Cannot understand.
10-7
10-8
In service.
Note: Although this table lists the 10-
codes’ meanings in the form of a state-
ment, they can also be phrased as
questions (10-6: Are you busy?, 10-20:
What is your location?).
10-9
Repeat last message.
Negative (NO).
10-10
10-11
10-12
10-13
____________in service.
Stand by.
Report road/weather
conditions.
10-14
10-15
10-16
10-17
10-18
10-19
10-20
Information.
Message delivered.
Reply to message.
En route.
Urgent
Contact_______
What’s your location?
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If you suspect engine noise as a source,
turn off the engine and operate the CB
with the ignition set to ACC. If most or all
of the noise stops, the problem is in ve-
hicle's ignition or electrical system.
MAXIMUM RANGE
The maximum range and quality of CB
transmissions vary depending on the fol-
lowing typical conditions:
• The type and quality of antenna
used.
The following few hints can help you re-
duce or eliminate such noise.
• The height of the antenna's mount-
ing location — the higher the
antenna, the greater the signal's
range
• Replace old ignition wires with new,
high-voltage,
wires.
noise-suppression
• Install noise suppressors on your
spark plugs, or install new spark
plugs that have built-in suppressors.
• The surrounding terrain — moun-
tains and tall buildings limit the
range.
• Be sure that the black wire ground
connection is securely attached to
either your vehicle’s battery's nega-
tive (GND) terminal or to a good
electrical chassis ground.
• Weather conditions.
• The number of nearby CBs operat-
ing on the same channel.
If problems persist, check your alterna-
tor or generator, voltage regulator, and
any stand-alone gauges. Noise from
these sources can be reduced or elimi-
nated using bypass capacitors at vari-
ous output voltage points.
REDUCING NOISE
The audio clarity enhancer (ACE) circuit
uses compander (compressor and ex-
pander) technology to improve commu-
nication quality. The circuit maintains
the dynamic range while increasing the
signal-to-noise ratio as the gain is auto-
matically controlled according to the in-
put signal level. This results in a
reduction in wide band noise.
Your local RadioShack store has a wide
selection of noise-suppression accesso-
ries.
The noise blanking (NB) circuit helps
keep background noise to a minimum.
However, strong sources of electrical
noise, generated by spark plugs or the
ignition of your car, or another radio,
might be more than the circuit can com-
pensate for.
17
21-1574.fm Page 18 Thursday, May 13, 1999 4:03 PM
TROUBLESHOOTING
If your CB is not working as it should, follow the suggestions below to see if you can
eliminate the problem. If the problem persists, take the CB to your local RadioShack
store for assistance.
Symptom
Check That:
OFF/VOLUME is turned on.
Reception difficulties
CB/WX/PA is set to CB
OFF/VOLUME is at a sufficient listening level.
RF GAIN is set to the correct level.
The microphone is securely plugged into MIC.
The antenna cable is securely plugged into ANTENNA
on the rear of the radio and attached securely to the
antenna at the other end.
Transmission difficulties The CB is turned on.
OFF/VOLUME is at a sufficient listening level.
The microphone is securely plugged into MIC.
All connectors (microphone, antenna, speakers) are
tight and secure.
When transmitting, you are fully pressing the micro-
phone talk button.
The antenna is properly mounted and not obstructed or
grounded.
No channel selection or CB/WX/PA is set to CB
only Channel 9 or 19
can be selected.
CH9/NOR/CH-19 is set to NOR
No operation at all.
The power supply and in-line fuse are functioning
(“Replacing the Fuses” on Page 20)
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21-1574.fm Page 19 Thursday, May 13, 1999 4:03 PM
CARE AND MAINTENANCE
Your RadioShack TRC-446 Deluxe 40-Channel Mobile CB is an example of supe-
rior design and craftsmanship. The following suggestions will help you care for
your TRC-446 so you can enjoy it for years.
Keep the CB dry. If it gets wet, wipe it dry immediately. Liquids might
contain minerals that can corrode the electronic circuits.
Use and store the CB only in normal temperature environments. Tem-
perature 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.
Handle the CB gently and carefully. Dropping it can damage circuit
boards and cases and can cause the CB to work improperly.
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
assistance.
19
21-1574.fm Page 20 Thursday, May 13, 1999 4:03 PM
REPLACING THE FUSES
The TRC-446's 2-amp fuses help pro-
tect your CB from power surges and
short circuits.
• If the red wire's fuse is blown,
replace it with a 2-amp, fast-acting
glass fuse, such as Cat. No. 270-
1007.
• If the orange wire's fuse is blown,
replace it with a 1-amp, fast-acting
glass fuse, such as Cat. No. 270-
1005.
Follow these steps to replace each fuse.
1. Make sure the power source and CB
are both off.
2. To open the fuse holder, push the
fuse holder ends together, then turn
either end counterclockwise and
release it.
3. If the fuse is blown, replace it.
Caution: Do not use a fuse with rat-
ings other than those specified here.
Doing so might damage your TRC-
446.
4. Close the fuse holder by pushing the
fuse holder ends together, then turn
either end clockwise.
20
21-1574.fm Page 21 Thursday, May 13, 1999 4:03 PM
SPECIFICATIONS
GENERAL
Channels ................................................................................................. 40 Channels
Frequency Range ........................................................... 26.965 MHz to 27.405 MHz
Power Requirements ........................ .. 13.8V DC (12–16 Volts DC, Negative Ground)
Dimensions (HWD) ............................................................... .. 21/4 × 71/4 × 77/8 Inches
(57 × 184 × 200 mm)
Weight ................................................................................................. 3.1 lbs (1.4 kg)
RECEIVER
Sensitivity .............................................................. 0.5 µV or better for 10 dB (S+N)/N
Adjacent Channel Rejection ......................................................... 50 dB (at 10 kHz)
Audio Output ............................................................................ 4.5 Watts (Maximum)
Frequency Response ............................................................................ 450–2500 Hz
Intermediate Frequency ............................................................... 1st IF: 10.695 MHz
2nd IF: 455 KHz
Cross Modulation ............................................................................................... 50 dB
Squelch ..................................................................... Adjustable from 0.5 µV to 1 mV
TRANSMITTER
Output Power ...................................................................... 4 Watts (FCC Maximum)
Type of Modulation .............................. AM Double-Sideband, Full Carrier Modulation
Modulation Capability ........................................................................................ ±90%
Spurious Emission ......................................................................... Less than –70 dB
Frequency Tolerance ...................................................................................... ±200 Hz
Antenna Impedance ....................................................................................... 50 Ohm
Current Drain ....................................... (13.8-volt supply) 1 Amp with No Modulation
1.6 Amps with 80% Modulation
21
21-1574.fm Page 22 Thursday, May 13, 1999 4:03 PM
PUBLIC ADDRESS
Output Power ............................................................................ 4.2 Watts (Maximum)
Current Drain (at maximum power) .............................................................. 1.2 Amps
WEATHER RADIO
Frequency Coverage (MHz) ........................................................................... 162.400
162.425
162.450
162.475
162.500
162.525
162.550
Specifications are typical; individual units might vary. Specifications are subject to
change and improvement without notice.
22
21-1574.fm Page 23 Thursday, May 13, 1999 4:03 PM
NOTES
23
21-1574.fm Page 24 Thursday, May 13, 1999 4:03 PM
Limited Ninety-Day Warranty
This product is warranted by RadioShack against manufacturing defects in material and workman-
ship under normal use for ninety (90) days from the date of purchase from RadioShack company-
owned stores and authorized RadioShack franchisees and dealers. EXCEPT AS PROVIDED
HEREIN, RadioShack MAKES NO EXPRESS WARRANTIES AND ANY IMPLIED WARRANTIES,
INCLUDING THOSE OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE,
ARE LIMITED IN DURATION TO THE DURATION OF THE WRITTEN LIMITED WARRANTIES
CONTAINED HEREIN. EXCEPT AS PROVIDED HEREIN, RadioShack SHALL HAVE NO LIABIL-
ITY OR RESPONSIBILITY TO CUSTOMER OR ANY OTHER PERSON OR ENTITY WITH RE-
SPECT TO ANY LIABILITY, LOSS OR DAMAGE CAUSED DIRECTLY OR INDIRECTLY BY USE
OR PERFORMANCE OF THE PRODUCT OR ARISING OUT OF ANY BREACH OF THIS WAR-
RANTY, INCLUDING, BUT NOT LIMITED TO, ANY DAMAGES RESULTING FROM INCONVE-
NIENCE, LOSS OF TIME, DATA, PROPERTY, REVENUE, OR PROFIT OR ANY INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, EVEN IF RadioShack HAS BEEN AD-
VISED OF THE POSSIBILITY OF SUCH DAMAGES.
Some states do not allow the limitations on how long an implied warranty lasts or the exclusion of in-
cidental or consequential damages, so the above limitations or exclusions may not apply to you.
In the event of a product defect during the warranty period, take the product and the RadioShack
sales receipt as proof of purchase date to any RadioShack store. RadioShack will, at its option, un-
less otherwise provided by law: (a) correct the defect by product repair without charge for parts and
labor; (b) replace the product with one of the same or similar design; or (c) refund the purchase
price. All replaced parts and products, and products on which a refund is made, become the prop-
erty of RadioShack. New or reconditioned parts and products may be used in the performance of
warranty service. Repaired or replaced parts and products are warranted for the remainder of the
original warranty period. You will be charged for repair or replacement of the product made after the
expiration of the warranty period.
This warranty does not cover: (a) damage or failure caused by or attributable to acts of God, abuse,
accident, misuse, improper or abnormal usage, failure to follow instructions, improper installation or
maintenance, alteration, lightning or other incidence of excess voltage or current; (b) any repairs
other than those provided by a RadioShack Authorized Service Facility; (c) consumables such as
fuses or batteries; (d) cosmetic damage; (e) transportation, shipping or insurance costs; or (f) costs
of product removal, installation, set-up service adjustment or reinstallation.
This warranty gives you specific legal rights, and you may also have other rights which vary from
state to state.
RadioShack Customer Relations, 200 Taylor Street, 6th Floor, Fort Worth, TX 76102
04/99
We Service What We Sell
RadioShack
A Division of Tandy Corporation
Fort Worth, Texas 76102
937485
Printed in Thailand
05A99
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