Cobra 25 NW ST Operating Instructions Manual

How to Use Your

Cobra 25 NW ST

Contents

Features...........................................................................................1

The CB Story..................................................................................A1

FCC Regulations
FCCWarnings
Included Accessories

Controls & Indicators................................................................A2

Our Thanks toYou......................................................................A3

SoundTracker

™

Customer Support

Installation

Location.......................................................................................2

Mounting and Connection...................................................2

Antennas

CB Antenna................................................................................6

Marine Installation...................................................................6

Ignition Noise Interference ...................................................7

Operating Your 25 NW ST

Turning On Your CB.................................................................8

Setting Channel Selector.......................................................9

To Receive...................................................................................10

Selecting a Channel................................................................10

S-Meter.........................................................................................11

SoundTracker™System.........................................................12

Activating SoundTracker™..................................................13

Dimmer Control........................................................................14

RF Gain Control.........................................................................14

Setting Squelch.........................................................................15

ToTransmit.................................................................................17

Setting Dynamike ....................................................................18

Transmit.......................................................................................19

RF Meter......................................................................................19

External Speaker.......................................................................20

PA (Public Address)..................................................................21

ANL (Automatic Noise Limiter) Switch.............................23

NB,OFF (Noise Blanker) Switch...........................................23

Temporary Mobile Set-Up.....................................................24

Home And Office Set-Up.......................................................25

HowYour CB Can ServeYou...................................................27

A Few Rules You Should Know............................................27

Channel 9 Emergency Messages.......................................27

CB 10 Codes...............................................................................29

Frequency Ranges......................................................................31

25 NW ST Specifications..........................................................32

Warranty Information..............................................................33

Optional Accessories.................................................................34

Order Form....................................................................................36

If You Think You Need Service.............................Back Cover

Features of This Product

• 40 CB Radio Channels

• SoundTracker™System

• Heavy-Duty Dynamic
Microphone

• Full 4 Watts AM RF Power Ou t p u t

• Instant Channel 19 and 9

• Front Panel 4-Pin Microphone
Connector

• Switchable Noise Blanker

• Switchable Automatic
Noise Limiter

• Adjustable Dynamike Boost

• Tactile Controls

• Illuminated Front Panel

• Dimmer Control

• RF Gain

• 9 ft.mic cord

1

CAUTION: TO REDUCE THE RISK OF ELECTRIC

SHOCK DO NOT REMOVE COVER (OR BACK)

NO USER SERVICEABLE PARTS INSIDE

REFER SERVICING TO QUALIFIED SERVICE

P E R S O N N E L

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

!

!

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InstallationInstallation

Location

32

Mounting and
Connection

Mounting and Connection

Hold the radio with the mounting bracket in
the exact desired location. If there is no inter­ference,remove the bracket and use it as a
template to mark the location for the mount­ing screws.

Location

Plan location of transceiver and microphone
bracket before starting the installation.

Select a location that is convenient for operation,
yet does not inte rfe re with the dri ver or passenger.

The transceiver is usually mounted to the under­side of the dash with the microphone bracket
beside it.

Note

The transceiver is held in the
universal mounting bracket by
two thumbscrews which allow
for adjustment at a convenient
angle.

The bracket includes two self­tapping screws and star wash­ers.The mounting must be
mechanically strong,conve­niently located.

continued

Drill the holes and secure the bracket.

2

1

Connect the antenna cable plug to the recep­tacle marked “ANT” on the back of the unit.

3

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InstallationInstallation

54

Note
Before installing the CB radio,

visually check the vehicle’s
battery connection to deter­mine which terminal, positive
or negative,is grounded (pos­itive is the larger of the two)
to the engine block (or chas­sis).A negatively grounded
vehicle has its negative lead
grounded to the chassis.

Note

Connecting to an accessory fuse
prevents the unit from being left
on accidentally,and also per­mits operating the unit without
running the engine.

Note

In positive ground vehicles the
red wire goes to the chassis and
the black wire is connected to
the ignition switch.

In a negative grounded vehicle,connect the
red lead of the DC power cord to an accessory
12 volt fuse.

Connect the black lead to the negative side of
the vehicle.This is usually the chassis.Any con­venient location with a good electrical contact
(remove paint) may be used.

4

5

Plug power cable into back of unit marked
“Power”. Be sure to observe polarity markings.

Mount the microphone
bracket on the right side
of the unit (driver’s left)
using two screws sup­plied.Bracket should be
placed under the dash
so microphone is readily
accessible.

6

7

Attach the 4-pin microphone cable to recepta­cle on front of unit and Install unit in bracket
securely.

8

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Ignition Noise InterferenceAntennas

Use of a mobile receiver at low signal levels is
normally limited by the presence of electrical
noise.The primary source of noise in automobiles
is from the alternator and ignition system.
Typically,when signal level is adequate,the back­ground noise does not present a serious problem.
Also,when extremely low level signals are being
received,the transceiver may be operated with
the vehicle’s engine turned off.The unit requires
very little current and therefore will not signifi­cantly discharge the vehicle’s battery.

Even though the Cobra 25 NW ST has an auto­matic noise limiter,in some installations ignition
interference may be high enough to make good
communications impossible.Many possibilities
exist and variations between vehicles require
different solutions.Consult your COBRA dealer or
a 2-way radio technician for help in locating the
source of a severe noise.

CB Antenna

Since the maximum allowable power output of
the transmitter is limited by the FCC,the antenna
is critical in affecting transmission distance.Only
a properly matched antenna system will allow
maximum power output.Cobra loaded type
antenna models are highly recommended for
most installations.Consult your Cobra dealer for
further details,or call 773.889.3087 and speak to
a Cobra representative.

Marine Installation

The transceiver will not operate at maximum effi­ciency in a boat without a ground plate,(unless it
has a steel hull).Before attempting installation ,
consult your dealer for information regarding an
adequate grounding system and prevention of
electrolysis between fittings in the hull and water.

CB Antenna

7

Note

For optimum performance in
passenger cars the ideal anten­na location is on the center of
the roof.Second choice is on the
center of the trunk.

Note

Because many newer trucks
feature fiberglass door skins,the
outside mirror must be ground­ed to the chassis via a ground
strap,if the antenna is mounted
on the mirror bracket.

Note

3-way Combination Antennas
are also available which allow
operation of all three bands
(AM-FM & CB),using a single
antenna.However,this type of
antenna usually results in less
than normal transmit and
receive range when compared
to a standard-type“Single
Band”CB antenna.Call

773.889.3087 for further infor­mation.

6

1

A standard antenna connector is provided
on the transceiver for easy connection.

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The CB/PA button should be in the
CB position.

Operation

9

Operation

Turning On Setting Channel

Selector

8

Turning On

Make sure the power cord,antenna and micro­phone are connected to their proper connectors
before starting.

Setting Channel Selector

2

1

Ro t ate the On/Off Volume knob c l oc kw i s eto
a normal listening level.

Select one of forty channels and adjust
volume.The selected channel is indicated by
the LED readout directly above the channel
selector knob

1

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Rotate the On/Off Volume knob clockwise
the green RT/TX LED will be illiuminated.

Operation

11

Operation

10

S-Meter

S-Meter

Swings proportionately to strength of incoming
signal when receiving.

Switch to NOR to select desired channel.

1

Selecting A
Channel

Selecting A Channel

Note

Switch to 9 (Emergency) or 19
(Information) for instant access
to these channels.

To Receive

1

To Receive

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OperationOperation

1312

Activating
SoundTracker

™

Push and release the ST button.Red LED
is illuminated when SoundTracker™ is
turned on.

1

The SoundTrackerTMSystem

While previous systems only “blanket out”or limit

noise in higher sound frequencies, the revolution-

ary new SoundTrackerTMSystem actually reduces
noise while leaving the signal intact in the recep­tion mode. In the transmission mode,it actually
strengthens the signal,providing you with a
significant reduction in noise on reception
and transmission.

Sound clarity is measured by the ratio
of the signal level to the noise level.
The higher the signal-to-noise ratio,
the better the sound.

How SoundTrackerTMWorks

On Reception - “Cuts noise coming in”

With a normal CB,distant signals fall below
the squelch level and are unintelligible.With a
SoundTrackerTMCB,the noise level is cut up to

90%,which increases the signal-to-noise ratio

and dramatically improves signal clarity.This also
allows you to significantly reduce the squelch

level,which greatly expands your listening range.

OnTransmission - “Strengthens signals going out”

A SoundTrackerTMCB strengthens the transmit
signal by more effectively using the available RF
power output of the CB.The result is improved

transmission signal clarity and an expanded
transmission range.

Note

SoundTracker™ gives you
clearer,cleaner reception to
improve CB communications
while on the air.

Activating SoundTracker™

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