Icom IC-746PRO Manual page 85

RF/SQUELCH CONTROL
• Adjusts the RF gain and squelch threshold level.
– The squelch removes noise output from the speaker (closed
condition) when no signal is received.
• The squelch is particularly effective for FM. It is also available for
other modes.
• 12 to 1 o'clock position is recommended for any setting of the
[RF/SQL] control.
• The control can be set as 'Auto' (RF gain control in SSB, CW and
RTTY; squelch control in AM and FM) or squelch control (RF gain is
fixed at maximum) in set mode as follows.