Squelch; Rf Gain; Selecting A Channel; Channel 9/Nor/Channel 19 - Cobra 19 DX IV Series Owner's Manual

Operation
Operating Your Mobile Radio
Operation

Squelch

This control is used to cut off or eliminate receiver background noise in the absence of an
incoming signal. Adjust until the receiver noise disappears. This will require the incoming
signal to be slightly stronger than average receiver noise. Further clockwise rotation will
increase the threshold level which a signal must overcome in order to be heard. Only
strong signals will be heard at a maximum clockwise setting.
Squelch is the "control gate" for incoming signals.
To squelch your radio:
Adjust Squelch/RF Gain Knob
1. Full clockwise rotation closes the gate,
allowing only very strong signals to enter.
2. Full counterclockwise rotation opens
the "gate," allowing all signals in.
3. To achieve the Desired Squelch Setting (DSS),
turn the Squelch control counterclockwise until
you hear noise. Now turn the control clockwise
just until the noise stops. This is the DSS setting.
Gate Open
Gate Closed
Strong Signals Strong Signals
Medium Signals Medium Signals
Weak Signals Weak Signals
Noise
Noise

RF Gain

This control is used to adjust receiver sensitivity. Maximum sensitivity allows
weak signals to be received. However, very strong signals (such as from a nearby
transmitter) can cause distortion at that setting. Adjust until the distortion disappears.
Reducing the receiver's RF Gain eliminates distortion from very strong incoming signals.
To set RF Gain:
Adjust Squelch/RF Gain Knob
1. Full counterclockwise rotation minimizes
gain for maximum distortion control.
2. To achieve the desired level of distortion control, turn
the RF Gain knob counterclockwise until
the distortion is eliminated.
3. After moving away from the strong signal,
turn the RF Gain knob fully clockwise to
receive all possible signals.
English
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Desired Squelch Setting (DSS)
Strong Signals
Medium Signals
Weak Signals
Noise
Operation
Operating Your Mobile Radio
Operation

Selecting a Channel

Channel Selector Knob
Rotate the Channel knob clockwise
until desired channel is displayed.

Channel 9/NOR/Channel 19

Channel 9/NOR/Channel 19 Button
Set CH 9 to obtain instant access
to the emergency channel.
Set NOR position to use the channel knob
to choose any of the 40 channels.
Set CH 19 to obtain instant access to
the information and calling channel.

CB/PA

CB/PA Button
In the CB position, the PA function is disabled and the unit will
transmit and receive on the selected channel.
The PA function should not be used unless a PA speaker
is connected.
In the PA position, the transmit function is disabled and
the microphone output will go only to the PA speaker.

S/RF Power Meter

S/RF Power Meter
Shows relative transmitter RF output power
and input signal strength when receiving.
The Liquid Crystal Display (LCD) segments
increase with signal strength.
TX Indicator
TX Indicator
The TX Indicator will light when in the
transmit mode. "Busy" will appear when
there is an incoming signal.
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Nothing Comes Close to a Cobra ®
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