Cobra 18 WXST II Operating Instructions Manual page 7

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.
OFF
Operation
Gate set to Desired
Squelch Setting (DSS)
STRONG SIGNALS
MEDIUM SIGNALS
WEAK SIGNALS
NOISE
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