on 3/31/97, Wayne Smith <wsmith@cyberdrive.net> wrote:
>>Subject: [16221] GM20 LOUD sidetone
>>Hi Group, Does anyone have any suggestions for lowering the sidetone level
>>on the GM20?? Otherwise the rig performs flawlessly. Any suggestions
would
>>be appreciated. Best 72 K8FF
First, check the two resistors immediately above the MC1350 IF amplifier.
They should both be 100-ohm values. Early versions of the manual had an
error in the pictorial (the schematic was correct), but that was resolved
quite a while ago. If that checks out OK, the 1M resistor shunting the
source-drain of Q1 (MPF102) may be replaced with a resistor of larger value.
This change reduces the level of sidetone audio 'bleeding through' to the AF
amplifier.
73, Dave Benson- NN1G
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