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WiNRADiO G3XX VHF/UHF Receiver
Receiver Gain Control
There are three hardware controls related to the receiver gain: AGC, Manual
IF Gain and Attenuator.
IF Gain and Attenuator.
AGC
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. This can be done automatically
using AGC (Automatic Gain Control) or manually, using manual IF Gain
control.
very weak to very strong. This requires the sensitivity of the receiver to vary
according to the incoming signal strength. This can be done automatically
using AGC (Automatic Gain Control) or manually, using manual IF Gain
control.
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).
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.
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, sensitivity appears to be very low, check the AGC
setting first.
or, on the other hand, sensitivity appears to be very low, check the AGC
setting first.
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