User Manual

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Mute Control
Next to the Volume control is the Mute button, which allows you to switch
off the audio output quickly. It is faster to use than setting the volume to
zero, with the added benefit of not changing the set volume level. To use the
mute control, simply click on this button. Click again to release.
AGC
The AGC (Automatic Gain Control) has four settings: Off, Slow, Medium
and Fast. These make it possible to disable the AGC, or to select the speed
with which the AGC reacts. Typically, the AGC would be in the Medium
position.
AGC Control
The receiver must process a considerable variation of signals, ranging from
very weak to very strong. This requires the sensitivity of the receiver to vary
according to the incoming signal strength.
The incoming signal can vary in intensity, with changing propagation
conditions, and also depending on the modulation type and content. For
example, with CW signals (where information is transmitted by keying the
transmitter on and off), the signal strength will vary substantially during the
transmission. The demodulated signal will then sound better with a slow
AGC (as the receiver will not have time to increase the gain during the “off”
intervals, and increase the background noise and causing a raspy sound).
On the other hand, use fast AGC when listening to especially weak signals
buried in static and noise. Otherwise, each new burst of noise would
desensitize the receiver for a long time and you could miss long periods of
useful transmissions.
If unsure, use the medium speed AGC setting.
It is easy to forget that AGC has been disabled. If the signal sounds
distorted, or, on the other hand, if the sensitivity appears to be very low,
check the AGC setting first.