[AMRadio] Modulator feedback

Rick Brashear rickbras at airmail.net
Fri Mar 17 21:35:28 EST 2006

Jim, you have a dandy idea there.  The plate supply for the drivers is 
kind of weird.  When I was going through the transmitter I replaced most 
of the components in the modulator section as most were out of 
tolerance.   Maybe I made a mistake, I'll sure check.  Thankfully, the 
modulator deck can be accessed (by standing on your head!) without 
breaking down the entire transmitter.  If that bias is off it could sure 
cause some strange happenings. 

Thanks a million, I'll follow your advise.

James M. Walker wrote:

> I'll bet you a nickel the bias supply has a problem, the plate supply
> for the 2A3s is not normal the plate supply is achieved by putting a
> negative voltage on the 2A3s cathode to raise hte plate to 360 volts.
> Sounds like the bias supply voltage is off. Check the manual and then
> the components that provide voltage to the 2A3s
> Jim

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