[Johnson] Johnson Invader AGC Circuit

[David C. Hallam]

Can anyone explain the to me the AGC circuit in the Invader?  I have 
been trying to trace the circuit and get lost in the various switches.  
How effective is it?  In operation, I find it is very easy to overdrive 
the final amp in my 2000.  Turning the audio control as little as a 
quarter of the distance between two numbers will make a big difference.  
With my Turner 95D mic I have to set it to almost number 2 and with the 
Electrovoice 676 about half way between numbers 2 and 3.  Anything more 
with this setting, I can see the grid current going over 10 mA.  I know 
the manual says 15 mA on voice peaks is permissible, but I have gotten 
reports of distorted audio.

David
KW4DH

-- 
There are two possible outcomes: if the result confirms the hypothesis, then you've made a measurement.
If the result is contrary to the hypothesis, then you've made a discovery.
Enrico Fermi



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