Sunday, July 11, 2010

AGC circuit working


I started with an audio derived AGC circuit from the 2010 ARRL handbook which uses 3 op-amps. I modified this slightly to work with the single supply LM124 op-amp. Additional modifications included changing the first stage from non-inverting to inverting and making it a gain stage rather than a buffer.

Results seem to be very good so far when testing the receiver with the signal generator and tuning in local amateur radio stations.

In final implementation i will leave room for further adjustments.