Cobra_25wx St Cb Tranciever_manual

1234TX  PWR
OPERATING INSTRUCTIONS FOR YOUR
40 CHANNEL
CITIZENS BAND 
2-WAY MOBILE RADIO
Model
25 WX ST
Cobra Electronics Corporation
6500 W. Cortland Street
Chicago, IL 60707
PRINTED IN HONG KONG ©COBRA ELECTRONICS CORP. 1997 480-210-P-001 

The Citizens Band lies between the shortwave broadcast and 10-meter Amateur radio
bands, and was established by law in 1949. The Class D two-way communications ser-
vice was opened in 1959. (CB also includes a Class Acitizens band and Class C remote
control frequencies.)
FCC regulations permit only ÒtransmissionsÓ (one party to another) rather than
ÒbroadcastsÓ (to a wide audience). Thus, advertising is not allowed on CB Channels
because that is Òbroadcasting.Ó
What Is Weather Radio?
NOAAWEATHER RADIO...

GENERALChannels40 
Frequency Range26.965 to 27.405 MHz.
Frequency ControlPhase Lock Loop (PLL) synthesizer.
Frequency Tolerance0.005%.
Operating Temperature Range-30¡C to + 50¡C.
MicrophonePlug-in dynamic.
Input Voltage13.8VDC nom.(positive or negative ground).
Current DrainTransmit: AM full mod., 1.5A(maximum)
Receive: Squelched, 0.3A; full audio output, 1.2A
(nominal).
Size8 5
/
8Ó D  x 7 9
/
32Ó W  x 2 13
/
64Ó H .
Weight4 lbs.
Antenna ConnectorUHF, SO-239.
Semiconductors26 transistors, 26 diodes, 4...

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4
Installation (Cont.)
Installation
3.
Connect the antenna cable plug to the standard receptacle on the unit. Most
CB antennas are terminated with a type PL-259 plug which mates with the
receptacle marked ANT.
4.
Connect the red lead of DC power cord to +13.8 VDC. In automobile instal-
lations, +13.8 VDC is usually obtained from the accessory contact in the fuse
box. This prevents the set being left on accidentally and also permits oper-
ating the unit without the vehicles engine running.
Before...

Ignition Noise Interference
Use of a mobile receiver at low signal levels is normally limited by the presence
of electrical noise. The primary source of noise in automobile installations is from
the alternator and ignition system in the vehicle. Under most operating conditions,when signal level is adequate, the background noise does not present a seriousproblem. Also, when extremely low level signals are being received, the transceivermay be operated with vehicle engine turned off. The unit requires very...

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6.CHANNELSELECTOR SWITCH.This switch selects any one of forty
Citizens Band channels desired. The selected channel is indicated by the
LED readout, directly above the channel selector knob.7.
S-METER. Swings proportionally to the strength of the incoming signal
during receiving. 
RF-METER. Swings proportionally to the RF output power while 
transmitting. 
8.CB-ANL/PASWITCH:Selects the mode of operation. In the CB-ANLpo-
sition, the PAfunction is disabled and the unit will transmit and receive
on the...

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Operating Procedure to Receive CB Broadcasts
1.
Be sure that the power cord, antenna and microphone  are connected to the
proper connectors before proceeding further. The PA/CB  should be in the 
CB position.
2.
Turn the radio ON by rotating the VOLUME CONTROLclockwise.
3.
Set the RF GAIN CONTROLfully clockwise.
4.
Rotate SQUELCH CONTROLcounterclockwise until incoming signal is heard.
5.
Set the Channel Selector Switch to the desired channel.
6.
Set VOLUME CONTROLto a comfortable listening level.
7....

1213
Operating Procedure for Public Address
1.
Connect a PAspeaker to the PAjack provided on the rear panel.
2.
Place PA/CB/ANLswitch into the PAposition.
3.
Depress push-to-talk switch on micÑspeak in normal voice.
4.
Adjust PAspeaker volume with front panel DYNAMIKE control.
When the Volume control is rotated clockwise, activity on the CB channel will
be heard through the PAspeaker.
Operating Procedure to Receive Weather Band
1.
Place CB/WX Switch in the WX position
2.
Turn the Weather Channel Selector...

1415
The COBRACB transceiver is specifically designed for the environment encoun-
tered in mobile installations. The use of all solid state circuitry and its light weight
result in high reliability. Should a failure occur, however, review the following,
then if necessary, replace parts only with identical parts. Do not substitute. Refer
to the schematic diagram and parts. 1.
Check connections to the source of power and make sure it is the 13.8 VDC
required to operate your radio.
2.
Check the fuse in the...

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A
Few Rules That Should Be ObeyedIf  You Think  You Need Service, Call 773-889-3087
If  You Think  You Need Service