[Johnson] Johnson Invader AGC Circuit

[Richard Knoppow]

     If you have the schematic as a PDF or can get the real one scanned, 
have it printed out blue print size and trace the wiring with hi-liters 
or colored pencils.  Sometimes figuring out complex schematics is like 
navigating a big freight yard.

On 2/16/2015 8:55 AM, David C. Hallam wrote:
> 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
>

-- 
Richard Knoppow
1oldlens1 at ix.netcom.com
WB6KBL