Collins KWM2-A AGC slow by simple modification?

neazoi

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I have a Collins KWM2-A HF transceiver for service (early model, schematic attached) and I wonder if the AGC can be made to have slower decay by a simple modification.
Collins has released some modifications and included them in the later models. However all of these require serious work to be done.
I am not exactly familiar of how the AGC is set, but I suspect I can add/alter a capacitor/resistor combination somewhere and make the AGC having slower response, especially in the decay.
 

Attachments

  • KWM-2-2A - 3rd ed Mar 1962 - schematic.pdf
    3.8 MB · Views: 40

Somewhere there must be a variable gain amp and a
filter for the gain control loop. Upping a R or C value
there ought to do it.

I bet it's somewhere between "AVC Rect" (automatic
volume control?) and 1st AF Amp, with the product
detector output filter looking quite likely.

Assuming this is about audio AGC and not RF gain....
 

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