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New file uploaded to BITX20@groups.io, Audio AGC Circuit

Dean Souleles
 

Time to give something back to the group.

I was looking for a an audio AGC that did not require a mod to the ubitx bored (because I am a solder wimp and scared of cutting traces!).   The very informative Alan Wolke, W2AE designed a stand alone audio leveler circuit for a SWL friend a few years back.  You can see it on hackaday and youtube.  I built it to go between my ubitx V5 and a West Mountain Radio ClearSpeech, DSP ClrSpkr.  I found I needed a little more drive for the speaker so I added a simple single transistor common emitter preamp.  Even on the breadboard it sounds great and works as advertised.  Strong signals which previously made me jump out of my chair are now under control with no loss of weak signals.  I also modeled it in LtSpice and amazingly enough I think I understand how it works.

I love this little radio.  Thanks to Farhan and the group of homebrewers who brought this to us.

73,
KK4DAS

73,