Automatic Gain Control (AGC)
WDSP AGC
We use this AGC by Warren Pratt which is part of the WDSP library. It was implemented
for the UHSDR because it has some more features that might potentially be useful in
very specific RX situations.
QUICK USER GUIDE FOR THE AGC:
1.
search for a free frequency --> band noise
2.
use encoder 2 to adjust the AGC threshold ("AGC"), so that the white text "AGC"
in the blue AGC indicator box starts to disappear
3.
With button M2 toggle focus of encoder 2 to next box
4.
Adjust AGC mode according to your personal preference and your band
situation: OFF = AGC off
FAS = fast
MED = medium
SLO = slow
LON = long
vLO = very long
the figure is the time constant = AGC WDSP DECAY for the AGC (given in centiseconds
= milliseconds*10, that decay time is the time the AGC needs to increase up to
maximum sensitivity again: thus 100 means 1 second). This is predefined for the
different AGC modes, but can be fine-tuned in the menu --> AGC WDSP DECAY
1.
Ready!
The AGC can be very easily and quickly adjusted for any specific receive and noise
situation. The WDSP AGC has double AGC detectors (one with short and one with long
time constant, thus potentially better for a suppression of short noise impulses) and a
hang AGC with adjustable hang time.
