Robotron Pty Ltd WRG3P Manuel D’Utilisation

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Finally, another convenient way of changing the volume is using the left and
right cursor keys on the keyboard.

Next to the Volume control is the Mute button, which allows you to switch off
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.

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.

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 (so that the receiver will not have time to increase the gain during the
“off” intervals, and so 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.