User's Manual

WiNRADiO G39DDC User’s Guide
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The AGC has six speed settings: Slow, Medium, Fast, User 1, User 2 and
User 3. These make it possible to select the speed with which the AGC reacts.
Typically, the AGC would be in the medium position.
For most practical applications, the medium setting is recommended. Slow
setting would be used especially with Morse code (CW mode), while fast AGC
speed might be appropriate for very noisy signals, where noise bursts might
temporarily desensitize the receiver if a slower AGC was employed.
While the timing of the slow, medium or fast speed settings is fixed, the
remaining three settings are user-definable, making it possible to specify the
Attack and Decay times:
The attack time is the speed with which the AGC reacts to a rising signal level,
while the decay time is the speed with which it reacts to a falling signal level.
These settings are recommended only for advanced users.
When enabled, the AGC tries to maintain the audio output at a constant level,
the AGC reference level. This level is also user adjustable under the gain tab,
using the Ref. level control:
The higher the AGC reference level, the stronger will be the signal at the input
of the demodulator. If this level is too high and the input signal too strong,
distortion may appear. On the other hand, decreasing the AGC reference level
will generally result in lower audio levels.
While in the automatic gain mode, the actual momentary gain will be shown in
the Gain window: