Re: Kit-Projects ND6T Ubitx AGC
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hi!
ok, what kind of swings should we be seeing for the volume input into the AGC versus the S meter? That way I can check it at the same time I get data for you. Sorry, this was on the project list after finishing a bitx40 repair/update for a friend.
-a
Tim
I see what you are looking at - wow.? Likely the change to R70 was done to better center the volume control when the output audio amplifier was changed - innocent except for its impact to this AGC circuit.?
I would suggest launching the AGC circuit at the input of R70 (aka TP21), instead of the output, to remove the effect of this added resistance.? I am just slightly wary of direct connection to the MOSFET, so why not a 10 or 100 ohm series resistor to feed into the AGC input?? Try this small change, and see if it works with v4.?
On the other resistor - I suggest visiting the K3PZN ubitx web page to obtain a nice mod for sidetone level.? I don't see this impacting AGC action.?
I feel better now that you have identified a reason for the fine ND6T AGC not working in my ubitx - and I think it is impacting my s-meter experiments also.?
73 Curt
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