Icom IC-746PRO Manual page 124

• AGC (Automatic Gain Control)
– What is the AGC?
• The AGC controls receiver gain to produce a constant audio output level,
even when the received signal strength is varied by fading, etc. Select
"FAST" for tuning and select "MID" or "SLOW" depending on the
receiving condition.
• Push momentarily to change the time constant of the AGC.
• Push for 1 sec. to enter to the
AGC 1
AGC set mode.