Oops AGC. It said that at first, and then auto corrupt changed it to HVAC. Good 
times.

Dave Wise

> On Mar 12, 2024, at 9:56 AM, Cecil acuff <[email protected]> wrote:
> 
> It’s been my standard practice to replace all paper caps in the “A” model 
> radio.  You may be able to find the single culprit but next week, or month 
> there will be another. I would just bite the. Bullet and replace them all!
> 
> Cecil
> 
> Sent from my iPhone
> 
>> On Mar 11, 2024, at 5:44 PM, [email protected] wrote:
>> 
>> I followed Charles Steinmetz's troubleshooting procedure for AGC issues and
>> the following resulted after tuning to a very strong BCB station:
>> 
>> 
>> 
>> Voltage Terminal 3  & 4: -0.37V - not good
>> 
>> 
>> 
>> Then step 2:
>> 
>> 
>> 
>> Resistance Terminal 3: 460k - maybe passable
>> 
>> Resistance Terminal 4: 24.6k - horribly off spec
>> 
>> 
>> 
>> So, my problem is most likely in "any of the several dozen bypass caps on
>> the AGC line in the IF and RF sections, or leakage to ground in one or more
>> of the mechanical filters".
>> 
>> 
>> 
>> Now my ignorance shows up.  How do I identify what are bypass capacitors?  I
>> assume that these are capacitors that go to ground?
>> 
>> 
>> 
>> I also note that, on the very strong BCB station, I get no sound output
>> until the RF gain is up to 8, if that helps narrow down where I should start
>> searching.
>> 
>> 
>> 
>> Thanks in advance for any help.
>> 
>> 
>> 
>> Regards,
>> 
>> 
>> 
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