[Swan] Sensitivity and meter on 500

[Steve Sutfin]

Jeff, I just realized that I should have said the 2nd IF was a 12BA6,  
not 12BE6. Bit of an eyesight problem.
73,
Steve k7dna

On Jul 3, 2017, at 11:43 AM, Jeff wrote:

> Thanks Steve!
>
> C202 has been replaced by discrete caps under the chassis, so that  
> should rule out one.  I'll replace the 12BE6 as you suggest.
>
> I've also removed the grid, plate and load variables and sent them  
> to the dishwasher.  I'm getting intermittent faults with them, so  
> might be another variable.
>
>
> Jeff
>
>
>
> On 7/3/2017 2:29 PM, Steve Sutfin wrote:
>> Hi Jeff,
>>  This is in case my response didn't get thru the 1st time.
>> Both the 12BE6 2nd IF and the C202 CanCap have an effect on the S- 
>> Meter AND the AGC system which could result in low receiver  
>> sensitivity. I can see that happening with the 12BE6 after warm  
>> up. Something to look into.
>> 73,
>> Steve k7dna
>>
>> On Jul 3, 2017, at 7:11 AM, Jeff wrote:
>>
>>> Hi all -
>>>
>>> Seeking some advice on a 500.  This seems temperature related,  
>>> and I'm having a hard time tracking it down.  I picked up a  
>>> basket case, and have been slowly rebuilding it.  I have it  
>>> transmitting and receiving OK now, but only when it's cold.
>>>
>>> From a cold start, the s-meter and receive function works as  
>>> expected, with good meter swings on signal peaks.  However, as  
>>> the rig heats up, the s-meter deflects less and less until it  
>>> basically remains stationary.  I also begin to lose receive  
>>> sensitivity.  Compressed air blown at spots underneath the  
>>> chassis doesn't seem t have any effect, nor does air applied to  
>>> the air variables.  It just... dies out.
>>>
>>> Short of just starting to shotgun everything, does anyone have  
>>> any suggestions on where to start looking?
>>>
>>> Thanks...
>>>
>>> Jeff
>>>
>>> WB3JIH
>>>
>>>
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