Automatic Squelch (Asq); Manual Squelch - Albrecht AE 6290 Bedienungsanleitung

Each suppresses the channel noise by muting the speaker.
Squelch only unmutes the speaker for the received signal to be
heard if certain criteria are met.

5.5.1. Automatic squelch (ASQ)

Automatic squelch continuously
evaluates the noise level. If a
signal is received, it decreases
and the ASQ unmutes the speaker.
To turn ASQ on, press and hold
the ASQ button on the radio. The
active function is shown by the AQ
symbol in the display.
Press ASQ again shortly until ASQ.SET appears. You can now
set the ASQ in 9 levels, level 1 is the most sensitive.
Advantage: the highest sensitivity and thus the greatest range.
Disadvantage: can be disturbed by interferences such as
sunspot activity, other electronic devices, etc., so that the
speaker is activated even if no signal is received. In this case,
manual squelch or tone squelch should be used.

5.5.2. Manual squelch

To set the manual squelch, press the SQ button shortly.
SQL.SET will appear in the display.
By adjusting the squelch control, the channel noise is faded out.
The higher the SQ is set, the stronger the received signal must
be to open the squelch. Usually, the squelch is set to just barely
mute the speaker.
Advantage: Manual squelch can be set so that only close range
stations can be heard.
Disadvantage: Manual setting is required. If the squelch is
mistakenly set too high, it decreases the reception sensitivity
and thus the range.
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