>
>on 3/23/01 12:59 AM, measures at 2@vc.net wrote:
>
>>> At 28 MHz, the capacitance of the tube and
>>> the capacitance of the tune Cap are on the same order of magnitude.
>>
>> 5pF is the same as 20pF?.
>
>You forgot something, Rich. The tube socket adds stray capacitance. The
>effects of putting the tube into the chassis adds stray capacitance. And if
>your amp has more than one tube, those capacitances are all in parallel
>meaning they add.
>
>If I remember correctly, my 4-1000 has about 7 pf output C. However, in
>some reading that I did and conferring with some others on it, I determined
>that that actual capacitance in the circuit ended up being around 15 pF or
>possibly even higher. I am sure that similar effects occur in the SB-200 or
>SB-220, particularly since both these amps have more than 1 tube.
>
zzzzzzzz
>15 pF and 20 pF are quite close. That means that nearly half your
>circulating current ends up flowing thru the tube(s).
>
The suppressor oroblem occured only on 40m.
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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