Uniden AX 144 User Manual

uniden

AX 144 CB RADIO
OWNERS MANUAL

RADIO BACK PANEL VIEW

EXTERNAL
SPEAKER

PA Jack

ANTENNA SERIAL NUMBER
Connector

IMPORTANT!

The above pictorial display shows the location of the various accessory, antenna,
and power receptacles, as well as the SERIAL NUMBER.

You are urged to record your model number and your SERIAL NUMBER in the
spaces provided below;

Model

SERIAL NUMBER

- 1 -

GENERAL
Channels

Frequency Range
Frequency Control
Frequency Tolerance

Frequency Stability
Operating Temperature Range
Microphone

Input Voltage

Current Drain

Cabinet Dimensions
Weight
Antenna Connector
Semiconductors

Meter

Indicators

TRANSMITTER
Power Output

Modulation

Intermodulation Distortion

SSB Carrier Suppression

Unwanted Sideband

Frequency Response
Output Impedance
SSB Filter

Output Indicators

SPECIFICATIONS

40 AM, 40 LSB, 40 USB
26,965 to 27,405 MHz
Phase Locked Loop(PLL) synthesized circuitry
±0.005%

0,001%

-10°C to +50° C
Plug-in type; dynamic with push-to-talk switch
and coiled cord

13.8V DC nominal, 15.9V max,, 11,7V min.

(positive or negative ground).

Transmit: AM full mod,, 2.2A; SSB Maximum

output, 2A.
Receiver: AM & SSB with maximum audio

output, 0.6A.

7-9/32(W) X 9-5/64(D) x 2-9/32(H)

4.5 Lbs

UHF, SO-239
47 transistors, 5 integrated circuits, 66 diodes

and 6 light emitting diodes.

Illuminated; indicates relative power output and
received signal strength, green receive LED.
LED display; channel, emergency channel, TX/
RX and mode,

AW,SSB Maximum Legal Output Power
AM, high and low level Class B
SSB: 3rd and 5th order, better than -25 dB.

7th and 9th order, better than -35 dB.
Better than -55 dB
Better than -50 dB
AM and SSB: 350 to 2500 Hz.
52 ohms, unbalanced

10,695 MHz, 8 pole monolithic type
6dB@4,2(<Hz
60dB@7.0kHz
Meter shows relative RF output power; red
transmit LED.

- 2-

RECEIVER
Sensitivity

Selectivity
Cross Modulation

Image Rejection

I.F. Frequency
AM and SSB RF Gain Control
Automatic Gain Control

Squelch

Noise Blanker
Clarifier Range
Audio Output Power

Frequency Response

Distortion

Built-in Speaker

External Speaker {Not Supplied)

PA SYSTEM

Power Output

External Speaker for PA

SSB: Better than j25 itV for 10 dB

(S+Nl/N at greater than 'h watt of audio
output

AM: Better than ,5 [i\! for 10 dB

{S-(-N)/N at greater than Ys watt of audio

output
SSB and AM: 6 dB @ 4.2 kHz, 60 dB @ 7.0 kHz
More than 50 dB

More than 75 dB

AM and SSB: 10.695 MHz

Adjustable for optimum signal reception.
(AGC): Less than 10 dB change in audio output
for inputs from 10 to 500,000 microvolts.
Adjustable; threshold less than .5/jV.
RF type, effective on AM and SSB.
±1.0 kHz
3 watts into 8 ohms
350 to 2500 Hz

Less than 10% at 3 watts output.
16 ohms, round
8 ohms; disables internal speaker when con
nected.

3 watts into external speaker.

8 ohms (not supplied)

- 3 -

INTRODUCTION

UNIDEN has combined superb workmanship and modern styling with the very la
test state-of-art circuitry to bring you the new AX 144 Citizens Band Transceiver.
It has been especially designed to give you maximum performance and reliability.
Your AX 144 is completely factory aligned and quality assurance tested.
To obtain the maximum benefit and pleasure from your AX 144 please read very
carefully the contents of this manual before attempting to install or operate the
transceiver.

FEATURES

ALL SOLID STATE: 1C and Transistorized construction, with low current drain,
for a long, trouble-free life.

FULL 40-CHANNEL OPERATION: PLL frequency, synthesizer circuitry allows
transmission and reception on all 40-channels on AM, USB and LSB without the
purchase of any additional crystals.

LARGE LED CHANNEL DISPLAY: Channel number is displayed by use of LED
(light emitting diode) display for ease of channel selection.

CLEAN SIGNAL: Transmitter audio processing circuitry produces a clean signal
with maximum legal modulation, for best range.

QUIET RECEPTION: Effective squelch and automatic noise limiter and an RF
noise blanker for superior quieting.

EFFECTIVE AGC: Receiver amplified automatic gain control (AGO reduces the
effect of differences in received signal strengths. No distracting "blasting" and

"fading" of signals,

AN EFFICIENT TRANSMITTER; Provides maximum legal output power to the

antenna,

PUBLIC ADDRESS FUNCTION: Useful for paging and announcements,

TRI-COLOR LED MODE INDICATOR: Green for AM mode. Yellow for USB

mode and Red for LSB mode.

EMERGENCY CH 9 SWITCH: This switch enebles you to select emergency

channel (CH 9) regardless of the channel selector switch setting.

- 4 -

CHANNEL INFORMATION

Channel

1 26.965 21 27.215
2 26.975
3 26.985
4
5 27.015
6 27.025

7
8 27.055 28 27.285
9 27.065 29 27.295

10

11 27.085

12 27.105 32 27.325
13 27.115 33
14
15
16 27.155 36
17
18 27.175
19 27.185 39
20 27 205

Channel Frequency

in MHz

27.005

27.035

27.075 30

27.125 34

27.135 35 27.355

27.155 37

Channel

22
23
24
25
26
27

31

38 27.385

40 27.405

Channel Frequency

in MHz

27.225

27.255

27.235

27.245

27.265

27.275

27.305

27.315

27.335

27.345

27.365

27.375

27.395

To insure that you obtain the maximum performance from this radio, please read
carefully the following descriptions and operating instructions.

NOTE: This radio has been designed for operation in the 11 meter Citizens Band

Radio Service. It uses a frequency synthesizing circuit with Phase Locked
LoopIPLLI techniques to provide crystal controlled transmit and receive
operation on all 40 channels. The PLL circuitry assures ultraprecise
frequency control. It is designed to meet the Department of Commu
nication requirements applicable to equipment operating in the Citizens
Band Radio Service, and is not to be used for any other purpose MS312 of
the D.O.C. regulations defines operation in this service, and you are required
to read and understand these regulations prior to operating this equipment.

-5-

INSTALLATION

Location
Plan the location o1 the transceiwer and micfophone bracket before starting the

installation. Select a location that is convenient for operation and does not interfere
with the driver or passenger in the vehicle. In automobiles, the transceiver is usually
mounted to the dash panel with the microphone txacket beside it.

Mounting and Connection
This radio is supplied with a universal mounting bracket. The transceiver is held in

the bracket by the two thumb screws supplied, permitting adjustment to the most
convenient angle. The bracket must be mounted with the machine screws supplied.
The mounting surface must be mechanically strong. Proceed as follows to mount the
transceiver:

1 After you have determined the most convenient location in your vehicle, hold the

radio with mounting bracket in the exact location desired. If nothing interferes
with mounting it in the desired position, remove the mounting bracket bolts.
Before drilling the holes, make sure nothing will interfere with the instaliation of
the mounting bolts.

2. Connect the antenna cable plug to the standard receptacle on the rear panel. Most
CB antennas are terminated with a type PL 259 plug which mates with the
receptacle on the rear panel.

3 Connect the DC power input wire with the fuse |red) to +12V DC. This wire

extends from a plug which connects to the rear panel. In automobile installations,
+ 12V DC is usually obtained from the accessory contact on the ignition switch.

-6 -

This prevents the set being left on accidentally when the driver leaves the car and

also permits operating the radio without the engine running. You can locate the
accessory contact on most ignition switches by tracing the power wire from the
AM broadcast receiver in the car.

Note: See ground connection under GENERAL INFORMATION tor more detail.

4. Connect the black wire to ground. This is usualiy the chassis of the car. Any con
venient location with good electrical contact may be used, (remove paintl.

5. Mount the microphone hanger on the side of the unit or near the unit, using two
screws supplied. When mounting in an automobile, place the hanger on the dash

so the microphone is easily accessible.

GENERAL INFORMATION

GROUND CONNECTION

This radio may be installed and used in any 12V DC negative or positive ground
system vehicle. Most new U.S. and foreign made cars or small trucks use a negative
ground system while some older cars and some newer large trucks may use a positive

ground system.

1. Negative ground system: Connect the Red power lead from the radio to the
positive or [-t) battery terminal or other convenient point, and connect the Black
power lead to the chassis or vehicle frame or (-) battery terminal.

2. Positive ground system: In the case of positive ground system, connect the Black
power lead from the radio to the negative or (-| battery terminal or other
convenient point, and connect the Red power lead to the chassis or vehicle frame
or (+) battery terminal.

ANTENNA
This radio is designed to operate into a 52 ohm CITIZENS RADIO antenna. Best

results will be obtained from your transceiver if you use a good antenna, properly

installed. (Refer to the antenna installation instructions included with your antenna.)

A vertically polarized quarter-wavelength whip antenna provides the most reliable
operation and greater range. The shorter loaded-type whip antennas are more at
tractive, compact and adequate for applications where the maximum possible dis
tance is not required. Also, the loaded whip antennas do not present the problems of
height imposed by the full quarter-wavelength whip.

- 7 -

Mobile whip antennas utilize the metal body of the vehicle as a ground plane. When
mounted on a corner of the vehicle, they are slightly directional, in the direction of

the body of the vehicle. For all practical purposes, however, the radiation pattern is
non-directional. A slight directional characteristic will be observed only at extreme
distances. A standard antenna connector (Type SO-239) is provided on the

transceiver for easy connection to a standard PL-259 cable termination.
When installed in a boat, the transceiver wili perform most efficiently when

antenna used has been specifically designed for marine applications.

Before installing the transceiver in a boat, consult your dealer for information
regarding an adequate grounding system and prevention of electrolysis between fitt

ings in the hull and water.

BASE STATION OPERATION
To operate the transceiver from your home or office, using regular house current as

the power source, you will require a separate power supply capable of supplying 2.5
amps at a 13,8V DC output with a nominal input voltage of 1 20 volts AC, 50/60H2.
Simply connect the red ( + | and black (-) leads of the transceiver to the correspond
ing DC terminals of the power supply.

NOTE: Do not attempt to operate this transceiver by connecting directly to 117V

AC. When AC power supply Is used with the transceiver for base station

operation any Citizens Band beam, dipole, ground plane or vertical antenna

may be used, A ground plane vertical antenna will provide the most uniform

horizontal coverage.

REMOTE SPEAKER

The external speaker jack (EXT. SPKR) on the rear panel is used for remote receiver

monitoring. The external speaker should have 8 ohms impedance. When the external
speaker Is plugged in, the internal speaker is disconnected.

PUBLIC ADDRESS

An external 8 ohm 4-watt speaker must be connected to the (PA SPKR) jack located
on the rear panel when the transceiver is used as a public address system. The speaker
should be directed away from the microphone to prevent acoustic feedback. Physical
separation or isolation of the microphone and speaker is important when operating
the PA at high output levels.

- 8 -

OPERATING INSTRUCTIONS

The AX 144 operates on 40 AM channels, 40 Upper Side Band channels and 40
Lower Side Band channels.

When you receive the SSB signal in the proper mode, audio sound may be either
too high pitched or low pitched, indicating that your receiver may not be tuned to
the exact same frequency as the transmitter to which it is listening. The AX 144 is
equipped with a Clarifier. By tuning the Clarifier, you can slightly change the
frequency of the receiver, so you get a normal tone.

Mir /RF gain control

MODE SELECTOR

DIGITAL LED

CHS INDICATOR

OPERATING CONTROLS
Your AX 144 , designed for ease of operation, is provided with the following

operating controls:

1. OFF/ON VOLUME: To turn the transceiver on, rotate the control clockwise
past click. To turn the transceiver off, rotate the control counterclockwise past
click. Rotate the control clockwise for a comfortable audio volume level.

2. CHANNEL SELECTOR: This switch is used to select any one of the 40
Citizens Band channels. Channel 9 has been reserved by the D.O.C, for
emergency communications involving the immediate safety of life of individuals
or immediate protection of property. Channel 9 may also be used to render
assistance to a motorist.

3. MODE SELECTOR: This switch selects AM, USB or LSB mode of operation.
This selector changes the mode of operation of both transmitter and receiver
simultaneously.

Set the selector to the mode on which you wish to communicate. For easier

identification of the mode, LED mode indicator is provided in three different

colors, green for AM, yellow for USB, and red for LSB,

- 9 -

4. SQUELCH: The squelch control is normally set to a position which just
eliminates undesired background noise with no signal present. With the audio
volume adjusted to a satisfactory level, rotate the Squelch control clockwise to
the point where the sound from the speaker is cut off. In this position, there will
be no sound from the speaker until a signal is received. In order to hear weak
signals, it may be necessary to rotate the Squelch control counterclockwise,
allowing some background noise to be heard,

5. CLARIFIER: The clarifier is normally set to the center position. This feature
has several uses and can greatly enhance receiver operation. If a receive signal

is slightly off frequency, this control can be operated to optimize the receive

signal. This control is primarily intended to tune in SSB signals, but, it may be

also used to optimize the AM signal.

6. MIKE GAIN: This control is used to adjust, as required, microphone input

sensitivity for optimum amount of modulation in transmit UNIDEN's citizen's
band transceivers have been designed to permit the user to attain levels of
modulation up to 100% depending on the setting of the microphone gain
control, using the microphone provided with the unit. UNIDEN's automatic
compression and peak limiting circuits assure maximum modualtion with mini
mum distortion.

7. DIMMER SWITCH: This switch is used to adjust the brightness of the LED
channel display and the meter. DIM position reduces brightness.

8. CH9 SWITCH: This switch is for use when emergency communication is needed
on the emergency channel CH9. Pressing the CH9 switch activates CH9
regardless of the position of the channel selector switch. When CH9 switch is
pressed, the channel display is blanked and the CH9 indicator is activated.

9. PA-CB SWITCH: This control engages the PA function. The PA function should
not be used unless an external speaker is connected. In the CB position, the PA
function is disabled and the radio will transmit and receive on the selected
channel.

10. NB/ANL SWITCH: When the switch is placed in the NB/ANL position, both of
RF Noise Blanker and Automatic Noise Limiter circuits are activated. The
NB is very effective for repetitive impulse noise such as ignition noise. The
ANL reduces annoying hash-type noises.

11. RF GAIN: This control is used primarily to optimize reception in strong signal
areas. Gain is reduced by counterclockwise rotation of the control.

- 10 -

INDICATOR FUNCTION

1. S/RF METER: This meter displays relative transmitter RF output power when
transmitting, and input signal strength when receiving. The meter is illuminated
when power is on, the illumination can be adjusted by the DIMMER switch for
optimum brightness,

2. TX/RX INDICATOR: The TX/RX light in the upper right corner of the front
panel lights in red color when the microphone button is pressed and transmitter

is in operation. It lights in green color when the microphone button is released

and the receiver is in operation.

PRESS TO TALK MICROPHONE
The receiver and transmitter are controlled by the press-to-talk switch on the

microphone. Press the switch and the transmitter is activated. Release the switch
to receive. When transmitting, hold the microphone about three inches from your
mouth and speak at a normal voice level.

RECEIVE OPERATING PROCEDURE

1. Place the CB PA switch in CB position.

2. Turn the set on by turning the VOLUME CONTROL clockwise, past click.
NOTE: Microphone must be plugged in for receiver to operate.

3. Set the VOLUME CONTROL to a comfortable level.

4. Set the Mode Selector Switch to the desired mode.

5. Listen to the background noise from the speaker. Turn the SQUELCH
CONTROL slowly clockwise, until the noise just disappears. The Squelch is now
properly adjusted. The receiver will remain quiet until a signal is received. Do
not advance the control too far, or some of the weaker signals will not be heard.

6. Set the Channel Selector to the desired channel.

7. Adjust the CLARIFIER to clearly receive SSB or AM signals.

TRANSMIT OPERATING PROCEDURE

1. Select the desired channel of transmission,

2. If the channel is dear, depress the push-to-talk switch on the microphone and
speak in a normal voice.

- 11 -

WARNING

Operation of this equipment requires a valid station license issued by the Depart
ment of Communication Do not transmit with your equipment until you have

a license,

- 12 -

MAINTENANCE AND ADJUSTMENT

This transceiver ts especially designed for the environment encountered in mobile
installations. The use of all solid state circuitry and its light weight result in high
reliability. Should failure occur, however, replace parts only with identical parts. Do

not substitute.

- 13 -

- 14 -

CIRCUIT DIAGRAM FOR AX144

uniden"

12 MONTHS FULL WARRANTY

WARRANTOR: UNIDEN AUSTRALIA PTY, LTD. 345 Princes Highway, Rockdale.
N.S.W. 22ierUNIDEN'T

ELEMENTS OF WARRANTY. Uniden Australia warrants, for the durationof this war
ranty, its UNIDEN C8 Product to be free from defects in materials and craftsmanship
with only the limitation or exclusions set out below.

WARRANTY DURATION. This warranty shall terminate and be of no further effect
One (1) year after the date of original purchase of the Product or at the time the Pro
duct is (a) damaged or not maintained as reasonable and necessary, |bi modified, (cl
improperly installed, Id) Is repaired bysomeonsother Warrantorforadefector mal
function covered by this Warranty, or (e) used in a manner or purpose for which the
Product was not intended.

PARTS COVERED. This Warranty covers all components of the Products.
STATEMENT OF REMEDY. In the event that the Product does not conform to this

Warranty at anytime while this Warranty is effective. Warrantor will repair the defect
and return it to you prepaid, without charge for parts, service, or any other costs in
curred by Warrantor or its representatives in connection with the performance of this
Warranty. In addition, if the Product contains a defect or malfunction which Is not re
paired after a reasonable number of attempts by Warrantor to repair the Product, the
Product or defective compohem will at our discratioh, will be replaced without
charge, when the defective product is delivered to the warrantor at 345 Princes High
way, Rockdale. N.S.W. 321 £ free and clear of all liens and encumbrances. Please note
that while the Product will be remedied under this Warranty without charge, THIS
WARRANTY DOES NOT COVER OR PROVIDE EOR THE REIMBURSEMENT OR PAY
MENT OE INCIDENTAL OR CONSEQUENTIAL DAMAGES.

Somestatesdonotallowthisexclusionorlimitationofincidentalorconsequentialda­mages, so the above limitation or exclusion may not apply to you.

PROCEDURE FOR OBTAINING PERFORMANCE OF WARRANTY: In the event that
the Product does not conform to this Warranty, the Product should be shipped pre
paid, to Warrantor at 345 Princes Highway, Rockdale, N.S.W. 2216. THE ORIGINAL
OR COPY OFTHE SALES RECEIPTOR OTHER VALID EVIDENCE OF THE DATE OF THE
ORIGINAL PURCHASE MUST ACCOMPANY THIS PRODUCT.

LEGAL REMEDIES: This Warranty gives you specific legal rights, and you may also
have other rights which vary from state to state

UTUA01524TC

uniden*

Australia Pty. Ltd.

HEAD OFFICE;

345 Princes Highway, Rockdale, N.S.W. 2216

Phone: [phone]

Fax: [phone]

BRISBANE

3/12 Randall Street, Slacks Creek,
Old. 4127
Phone [phone]
Fax [phone]

MELBOURNE & TASMANIA

446-448 Bell Street, East Preston,
VIC. 3072
Phone [phone]
Fax [phone]

) Copyright 1992 Uniden Corporation

PERTH
23 Geddes Street, Balcatta,
W.A. 6021
Phone [phone]
Fax [phone]

ADELAIDE

72-74 Halifax Street, Adelaide
S.A. 5000
Phone [phone]
Fax [phone]

Printed in the Philippines