[Collins] 75A-4 AGC

[Kenneth Lopez]

Greetings,

My 75A-4 has been developing unusual symptoms over time.  After warm up 
sensitivity has been decreasing and S Meter indication dropping to nil.

Yesterday I turned it on, and there now appears to be no AGC.

I won't be digging into it right away, but wonder if anyone can give me 
some places to begin my investigations and troubleshooting.  I'm sure 
that one or more of you have run into a similar ACG related problem at 
one point or another.

Thanks,

Ken N6TZV