Tom,
I have no idea where the amp was oscillating. The tube is good for
operation at 250MHz+ so VHF oscillation is surely possible but it might
just as well have been HF. Screening and proper bypassing cured my problems.
As I said, the amp arced because of parasitics. My posting was because
"someone" said that would be impossible.. then again, there are different
types of parasitics... for one they differ in frequency...
Carry on, I'm out..
73/Peter SM2CEW
www.qsl.net/sm2cew
At 21:23 2001-01-19 , you wrote:
>> When rebuilding the screen supply for my amp I suddenly developed
>> arcing BIG time in the tank circuit something that had never happened
>> before. Screening the rectifiers and bypassing the cable feeding the
>> screen stopped all arcing. No changes what so ever were done in the
>> tank circuit to stop arcing.
>>
>> There is no doubt in my mind that parasitics caused the tank arcing.
>>
>> 73/Peter SM2CEW
>
>Hi Peter,
>
>I'm missing something.
>
>Are you actually telling us you had a parasitic in your screen
>supply wiring and rectifiers? Please tell us why you think it was a
>parasitic, and what frequency it was on.
>
>
>73, Tom W8JI
>w8ji@contesting.com
>
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|