Uniden Bearcat PC78LTXFM User manual

Owner’s Manual
Printed in Vietnam
U01UT434ZZZ(0)
®
PC78LTXFM

CUSTOMER CARE
At Uniden®, we care about you!
If you need assistance, please do NOT return this product to your place of
purchase.
Quickly find answers to your questions by:
1. Reading your owner’s manual.
2. Visiting our customer support website at www.uniden.com.
Images in this manual may dier slightly from your actual product.
Save your receipt/proof of purchase for warranty.
© 2022. All rights allowed by law are hereby reserved.
Uniden is a registered trademark of Uniden America Corporation.
Bearcat is a registered trademark of Uniden America Corporation.
Features, specifications, and availability of optional accessories are all subject to change without notice.

CONTENTS
DESCRIPTION.............................................................................. 5
EMERGENCY OPERATIONS .......................................................................... 5
FEATURES ...................................................................................................... 5
WHAT’S IN THE BOX...................................................................................... 6
FRONT VIEW .................................................................................................. 6
REAR VIEW..................................................................................................... 8
INSTALLATION............................................................................ 9
MOBILE INSTALLATION................................................................................ 9
Mobile Antenna........................................................................................... 9
Connecting the Power Cords..................................................................... 10
Ground Information.................................................................................. 10
USING YOUR PC78LTXFM........................................................ 11
TURN PC78LTXFM ON/OFF ........................................................................ 11
CB MODE...................................................................................................... 11
PA MODE...................................................................................................... 11
HI CUT .......................................................................................................... 12
TO TRANSMIT/RECEIVE.............................................................................. 12
MULTI-FUNCTION METER .......................................................................... 12
PREVENTIVE MAINTENANCE .................................................. 13
MAINTENANCE ......................................................................... 13
TROUBLESHOOTING ................................................................ 14
RADIO CODE DEFINITIONS ..................................................... 16
10-CODES..................................................................................................... 16
FCC PART 15.............................................................................. 17
FCC 20 CM STATEMENT ........................................................... 18
ONE-YEAR EXTENDED WARRANTY ........................................ 19

4

5
DESCRIPTION
Your Uniden PC78LTXFM is a high-quality communications device
designed for use in the Citizens Band Radio Service. It will operate on any
of the 40 AM/FM frequencies authorized by the Federal Communications
Commission (FCC).
The Citizens Band Radio Service is under the jurisdiction of the Federal
Communications Commission (FCC). Any adjustments or alterations
which would alter the performance of the transceiver’s original FCC type
acceptance, or which would change the frequency determining method,
are strictly prohibited. Replacement or substitution of crystal, transistors,
ICs, regulator diodes, or any other part of a unique nature, with parts
other than those recommend by Uniden, may cause violations of the
technical regulations in Part 95 of the FCC Rules or in violation of type
acceptance requirements in Part 2 of the rules.
EMERGENCY OPERATIONS
1. Set the switch to CH9 or turn Channel Selector knob to Channel 9.
2. Press the microphone PTT switch and speak clearly.
3. If there is no response, select an active channel and ask that party
to relay your emergency broadcast on Channel 9.
All channels except Channel 9 may be used for normal communication.
Channel 9 is reserved by the FCC for emergency communication
involving the immediate safety of individuals or protection of property.
Channel 9 may also be used to render assistance to others.
This is an FCC rule and applies to all operators of CB radios.
FEATURES
CB AM & FM 40 CH (4W)
PA (Public Address)
Channel 9 Direct Tune
TX/RX Multicolor LED (RED and GREEN)
AWI (Antenna Warning Indicator) LED (RED)
ANL (Automatic Noise Limiter)
NB (Noise Blanker)
HI CUT Adjustment

6
Dimmer Control
RF Gain Control (Variable)
MIC Gain Control (Variable)
Multi-Function Meter: RF Power, Signal strength, and SWR
Volume Control (Variable)
Squelch Control (Variable)
4-Pin Microphone Jack
WHAT’S IN THE BOX
Carefully unpack your PC78LTXFM and check the contents against this
list:
PC78LTXFM
CB 2-way mobile radio
Microphone
Mounting Bracket Kit
DC Power Cord
Owner’s Manual
Part 95 Subpart D (FCC Rules)
If any items are missing or damaged, visit our website at www.uniden.com
for further information.
Never use damaged products!
FRONT VIEW
2
110
3457
68
9
111217 16 15 14 13

7
Item Denition
1Multi-function meter: Measures SWR, RF and S signal strength.
2Microphone jack
3ON OFF - VOLUME/SQUELCH: Turns radio on or o; adjusts
speaker volume and squelch level (reduces background noise
when there is no incoming signal).
4MIC GAIN knob: Adjusts microphone sensitivity
5RF GAIN knob: Improves reception in strong signal areas.
6HI CUT knob: Adjust clockwise to reduce high frequency noise.
7SWR CAL: Calibrates the meter for Standing Wave Ratio (SWR)
measurements. (See page 12.)
8Channel knob: Selects channel.
9ANT LED: Indicates a high SWR condition in antenna system.
Check antenna, cable, and connections.
10 Channel Display: Displays current channel selection
11 RX/TX LED: Red-transmitting; green-receiving.
12 AM/FM switch: Toggle between AM or FM modulation.
13 CH9/OFF switch: Instantly tunes to emergency CB Channel 9. Turn
o to resume normal channel operations.
14 BRT/DIM switch: Adjusts the backlight LED brightness.
15 CB/PA: Selects CB (Citizen’s Band) or PA (Public Address).
Do not use PA function unless an external speaker is connected.
16 NB/ANL/ANL/OFF switch: Reduces external noise and
interference from vehicle ignition systems.
17 S/RF/SWR/ CAL switch: Selects meter function. S/RF- normal;
SWR and CAL are for SWR measurements only. See page 12 for
calibration procedures.

8
REAR VIEW
9
8
Item Denition
18 Antenna socket: Connects antenna cable to transceiver.
19 PA SP. jack: Connects external 8-ohm, 4-watt speaker.
To prevent acoustic feedback, separate the microphone from the
speaker when operating the PA at high output levels.
20 EXT. SP. jack: Connects optional 8-ohm 4-watt speaker to remotely
monitor the receiver.
When the external speaker is plugged in, the internal speaker is o.
21 POWER connector: Connects DC power to transceiver.

9
INSTALLATION
MOBILE INSTALLATION
Plan the location of the transceiver and microphone bracket before
beginning installation.
1. Select a location that is convenient for operating the radio, but
does not interfere with the driver or passenger.
2. Install bracket with self-tapping screws provided.
3. Connect power cords (see page 10).
4. Attach the microphone bracket to the side of the radio.
5. Attach radio to bracket.
Mobile Antenna
WARNING! The antenna used for this radio must be installed at least 16.92
inches (43 cm) away from all persons. The antenna must not be collocated
or used with any other antenna or transmitter.
CAUTION: Never operate your radio with no antenna or with a damaged
antenna cable. This can damage the radio.
You must purchase an antenna to operate this radio. Because the
maximum power output of the transmitter is limited by the FCC, the
quality of your antenna is very important. To achieve the maximum
transmission distance, Uniden strongly recommends that you install only
a high quality antenna. You have just purchased a superior transceiver -
don’t diminish its performance by installing an inferior antenna.
Only a properly matched antenna system will allow maximum power
transfer from the 50 ohm transmission line to the radiating element.
Your Uniden dealer is qualified to help you select the proper antenna for
your requirements. A whip style antenna may be used for automobile
installation.
A short ‘loaded’ whip antenna is easier to install on an automobile, but its
efficiency is less than that of a full quarter-wave whip antenna.

10
Connecting the Power Cords
Uniden recommends connecting the power lead to the Ignition Switch
Accessory Terminal. This way, the transceiver is automatically turned off
when the ignition switch is turned off.
As an alternative, the power cord may be connected to an available
terminal on the fuse block or to a point in the wiring harness. However,
take care to prevent a short circuit. If in doubt, contact your vehicle
dealer for information.
This transceiver may be installed and used in any 12-volt DC negative
ground system vehicle.
Ground Information
Most newer U.S. and foreign made cars and small trucks use a negative
ground system. Some older cars, and some new large trucks, use a
positive ground system.
With a negative ground system, the negative (-) battery terminal is
usually connected to the vehicle motor block. If you cannot determine
the polarity system of your vehicle, contact your vehicle dealer for
information.
Negative Ground System
For negative ground systems, connect the red DC power cord from the
transceiver to the positive (+) battery
terminal or other convenient point.
Then connect the black power cord
to the vehicle chassis or negative (-)
battery terminal.

11
USING YOUR PC78LTXFM
TURN PC78LTXFM ON/OFF
Turn the VOLUME knob clockwise until the unit turns on and the display
backlight turns on.
Turn the VOLUME knob counter-clockwise to turn the unit off.
CB MODE
Be sure that the power source, antenna, and microphone are properly
connected before proceeding.
1. Turn the unit on. Set the volume to a comfortable level.
2. Set switch to CB.
3. Select AM or FM.
4. Turn the CH knob to select a CB channel.
5. Adjust HI CUT as needed.
6. Set noise limitations switch to NB/ANL.
7. Adjust squelch.
• Adjust SQUELCH knob fully clockwise so only strong signals
can get through.
• Adjust SQUELCH knob fully counter-clockwise until you hear
a hiss. Everything gets through - noise, weak signals, and
strong signals.
• Slowly adjust SQUELCH knob back clockwise until the hiss
stops. Only clearer signals get through.
Set SQUELCH only when the radio is not receiving a strong signal.
8. Press and hold PTT and check the multifunction meter. It will
show the RF output power.
9. Adjust RF GAIN knob set RF Gain sensitivity. Normally, the knob is
turned clockwise to maximum.
10. Set the brightness (BRT or DIM).
11. Set meter switch to S/RF.
PA MODE
Using the PA mode requires an optional speaker.

12
1. Switch to PA.
2. Press and hold PTT to speak.
3. Release when nished.
To prevent acoustic feedback, separate the microphone from the speaker
when operating the PA at high output levels.
If you are in PA mode but not pressing PTT, the radio receives CB
transmissions and transmits them through the PA speaker. You cannot
respond to the transmission.
HI CUT
The Hi Cut function reduces high frequencies and minimizes white noise.
Turn the HI CUT knob clockwise to reduce higher frequencies.
TO TRANSMIT/RECEIVE
Perform a voltage Standing Wave Ratio (SWR) measurement prior to using
the transmitter. An SWR ratio in excess of 2:1 may damage the transmitter.
Be sure to read and understand Part 95, FCC Rules and Regulations before
operating your transmitter.
1. Select a channel.
2. Adjust MIC GAIN.
3. When the channel is clear, press the microphone PTT and speak.
4. Release PTT when you are nished speaking to listen for the
response.
MULTI-FUNCTION METER
SWR Meter: Measures the standing wave ratio (SWR) of the antenna. Use
this meter to check the antenna system or to adjust your antenna to the
proper length.
To Measure SWR:
1. Set the meter switch to CAL.
2. Press and hold microphone PTT switch (Transmit).
3. Calibrate meter with SWR CAL knob by adjusting the needle to
the ▼ mark.

13
4. Move the meter switch to the SWR position while pressing the
microphone PTT switch.
5. Release the PTT switch.
A reading less than two is acceptable. Higher readings indicate a problem
in the antenna system. Problems may be caused by humidity, vibration,
a mistuned antenna, or corrosion. Check both ends of the coaxial cable
connector. Also check for damage to the cable or antenna. Tune the
antenna according to the instructions that came with the antenna.
RF Meter: Measures RF Output Power for transmitter. To use,
set the
meter switch at S/RF. Press microphone PTT switch to read transmitting
power.
S-Meter: Measures incoming signal strength. To use,
set the meter switch
at S/RF. The meter swings to indicate signal strength.
i.e. S 3, S 5, S 7 . . .
PREVENTIVE MAINTENANCE
Every six months:
1. Check the Standing Wave Ratio (SWR). See page 12.
2. Be sure all electrical connections are tight.
3. Inspect antenna coaxial cable for wear or breaks in shielding.
4. Be sure all screws and mounting hardware are tight.
MAINTENANCE
The PC78LTXFM is designed to give you years of trouble-free service.
There are no user-serviceable parts inside. Except for the fuse in the DC
power cord, no maintenance is required.
To replace a blown fuse:
1. Press ends of the fuse holder together. Twist to open.
2. Carefully separate the two pieces.
3. Remove the fuse and inspect. If blown, replace with the same
type fuse. Use only the fuse specied for your
PC78LTXFM . Failure
to do so may void your warranty.

14
TROUBLESHOOTING
In the event of system malfunction, perform the following procedures:
Problem Suggestion
Unit does not power up Check the ignition key position.
Check power cord connections.
Check fuse.
Check vehicle electrical system.
No reception Check microphone connection.
Set CB/PA to CB.
Check VOLUME and SQUELCH.
Check antenna.
Check antenna connection.
Adjust RF Gain.
Poor Reception Be sure that the transmitting and receiving
radios match (AM-AM or FM-FM).
Check VOL and SQ.
Be sure antenna SWR is normal.
Adjust RF Gain.
No Transmission Set CB/PA switch to CB.
Check microphone connection.
Adjust MIC Gain.
Low Transmission Be sure antenna SWR is normal.
Adjust MIC Gain.
Calibration does not move the
meter needle to the left side
Adjust the antenna length.
Check all antenna connections.
If you do not get satisfactory results after performing these checks, visit
www.uniden.com for information.
SPECIFICATIONS
GENERAL
Channels: 40
CB Frequency Range: 26.965 - 27.405 MHz
Frequency Control: PLL synthesizer
Antenna Impedance 50 ohms
Power Input : 13.8VDC

15
Current Drain:
TX:
AM Full Modulation: 2.1A (max)
FM - 1.6A (max)
RX: At no signal: 400mA
Operating Temperature: -22°F to 140°F (-30°C to 60°C)
Size (W x D x H): 7-9/32 in. x 7-51/64 in. x 2-13/64 in.
(without knobs and jacks)
Weight: 3 lb with microphone
Antenna Connector: UHF, SO-239
TRANSMITTER
Power Output: 4 watts
Emission Type: AM/FM
Hum and Noise
AM:
FM:
46dB
38dB
Frequency Tolerance ±0.003%
Spurious Harmonics Emission -70 dBc
Output Impedance: 50 ohm, unbalanced
RECEIVER
Sensitivity
AM at 10 dB (S+N)/N:
FM at 12dB SINAD:
-111dBm
-120dBm
Maximum Sensitivity (AM): -113dBm
Squelch Threshold -117dBm
Squech Tight: -47dBm
Signal Meter S-9: -67dBm
Audio Output Power (max): 5 watts
Audio Output (10% Dist.): 4.5 watts
Image Rejection: 80 dB typical
Adjacent CH Rejection: 60 dB typical
Internal Speaker Impedance: 16 ohms
Antenna Impedance 50 ohms
RF Gain Control: Adjustable for optimum signal reception
Noise Blanker: RF type
Squelch Sensitivity: Threshold -117dBm
Tight -47dBm
Frequency Response @6dB Down
1kHz, 0dB Reference:
200 to 3000 Hz

16
Internal Speaker Impedence: 16 ohms
PUBLIC ADDRESS SYSTEM
Audio Output (10% Dist.): 4 Watts
External Speaker for PA Speaker (not
supplied):
8 ohms when CB/PA switch is PA. The PA
also monitors the receiver; separate jack
provided.
Specications shown are typical and subject to change without notice.
RADIO CODE DEFINITIONS
10-CODES
The following list contains common“10-Codes” used by CB radio
operators for faster communication and better understanding.
Code Meaning Code Meaning
10-1 Received poorly 10-34 Trouble at this station
10-2 Receiving well 10-35 Condential information
10-3 Stop transmitting 10-36 Correct time is
10-4 OK, message received 10-37 Wrecker needed at
10-5 Relay message 10-38 Ambulance needed at
10-6 Busy, stand by 10-39 Your message is delivered
10-7 Out of service, leaving air 10-41 Please turn to channel
10-8 In service, subject to call 10-42 Trac accident at
10-9 Repeat message 10-43 Trac tie up at
10-10 Transmission completed,
standing by
10-44 I have a message for you
10-11 Talking too rapidly 10-45 All units within range please
report
10-12 Visitors present 10-50 Break channel
10-13 Advise Weather/ Road
conditions
10-60 What is next message number
10-16 Make pickup at 10-62 Unable to copy, use phone
10-17 Urgent business 10-63 Net directed to
10-18 Anything for us? 10-64 Net clear

17
Code Meaning Code Meaning
10-19 Nothing for you, return to
base
10-65 Awaiting your next message/
assignment
10-20 My location is 10-67 All units comply
10-21 Call by telephone 10-70 Fire at
10-22 Report in person to 10-71 Proceed with transmission in
sequence
10-23 Stand by 10-77 Negative contact
10-24 Completed last assignment 10-81 Reserve hotel room for
10-25 Can you contact 10-82 Reserve room for
10-26 Disregard last information 10-84 My telephone number is
10-27 I am moving to channel 10-85 My address is
10-28 Identify your station 10-91 Talk closer to microphone
10-29 Time is up for contact 10-93 Check my frequency on this
channel
10-30 Does not conform to FCC
rules
10-94 Please give me a long count
10-32 I will give you a radio check 10-99 Mission completed, all units
secure
10-33 EMERGENCY TRAFFIC 10-200 Police needed at
If you do not get satisfactory results after performing the above checks,
visit www.uniden.com for further information.
FCC PART 15
Changes or modifications not expressly approved by the party
responsible for compliance could void the user’s authority to operate the
equipment.
This device complies with Part 15 of the 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 interference received, including
interference that may cause undesired operation.

18
Note: This equipment has been tested and found to comply with the limits
for a Class B digital device, pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against
harmful interference in a residential installation.
This equipment generates, uses, and can radiate radio frequency energy,
and if not installed and used in accordance with the instructions, may
cause harmful interference to radio communications. However, there is
no guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one or
more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit dierent from
that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
FCC 20 CM STATEMENT
This equipment complies with FCC radiation exposure limits set forth
for an uncontrolled environment. This equipment should be installed
and operated with a minimum distance of 20cm between the radio
and your body. This transmitter must not be co-located or operating in
conjunction with any other antenna or transmitter.

19
ONE-YEAR EXTENDED WARRANTY
Important: Evidence of original purchase is required for warranty service.
WARRANTOR: UNIDEN AMERICA CORPORATION (“Uniden”)
ELEMENTS OF WARRANTY: Uniden warrants, for one year, to the original
retail owner, this Uniden Product to be free from defects in materials and
craftsmanship with only the limitations or exclusions set out below.
WARRANTY DURATION: This warranty to the original user shall terminate
and be of no further effect one year after the date of original retail sale.
The warranty is invalid if the Product is (A) damaged or not maintained
as reasonable or necessary, (B) modified, altered, or used as part of any
conversion kits, subassemblies, or any configurations not sold by Uniden,
(C) improperly installed, D) serviced or repaired by someone other than
an authorized Uniden service center for a defect or malfunction covered
by this warranty, (E) used in any conjunction with equipment or parts
or as part of any system not manufactured by Uniden, or (F) installed or
programmed by anyone other than as detailed by the owner’s manual for
this product.
STATEMENT OF REMEDY: In the event that the product does not conform
to this warranty at any time while this warranty is in effect, warrantor
will either, at its option, repair or replace the defective unit and return
it to you without charge for parts, service, or any other cost (except
shipping and handling) incurred by warrantor or its representatives
in connection with the performance of this warranty. Warrantor, at its
option, may replace the unit with a new or refurbished unit. THE LIMITED
WARRANTY SET FORTH ABOVE IS THE SOLE AND ENTIRE WARRANTY
PERTAINING TO THE PRODUCT AND IS IN LIEU OF AND EXCLUDES
ALL OTHER WARRANTIES OF ANY NATURE WHATSOEVER, WHETHER
EXPRESS, IMPLIED OR ARISING BY OPERATION OF LAW, INCLUDING,
BUT NOT LIMITED TO ANY IMPLIED WARRANTIES OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE. THIS WARRANTY DOES NOT
COVER OR PROVIDE FOR THE REIMBURSEMENT OR

20
PAYMENT OF INCIDENTAL OR CONSEQUENTIAL DAMAGES. Some states
do not allow this exclusion or limitation of incidental or consequential
damages so the above limitation or exclusion may not apply to you.
LEGAL REMEDIES: This warranty gives you specific legal rights, and you
may also have other rights which vary from state to state. This warranty is
void outside the United States of America.
PROCEDURE FOR OBTAINING PERFORMANCE OF WARRANTY: If, after
following the instructions in the owner’s manual you are certain that
the Product is defective, pack the Product carefully (preferably in its
original packaging). The Product should include all parts and accessories
originally packaged with the Product. Include evidence of original
purchase and a note describing the defect that has caused you to return
it. The Product should be shipped freight prepaid, by traceable means, to
warrantor at:
Uniden America Corporation
C/O Saddle Creek
743 Henrietta Creek Road, Suite 100
Roanoke, TX 76262