>
>on 3/10/00 7:37 PM, measures at 2@vc.net wrote:
>
>>> And please show us some SCIENTIFIC
>>> proof that this "codswallop" as you call it really is "codswallop." Unless
>>> you can back up your claim scientifically, don't make it.
>>>
>> Do you believe that tubes gas up and fail when they are in the mfg.'s
>> sealed box.?
>
>Why not. If the gases are trapped in the surface of the metal why would
>some not escape? Also, since it is IMPOSSIBLE to create a perfect vacuum
>there is certainly some gas still left inside the tube.
>
>I see no problem.
>
>>
>>> And of course the resonance might vary from capacitor
>>> to capacitor. But one question is was it a series resonance or a parallel
>>> resonance?
>>>
>> Better ask Tom. {chortle].
>
>Why don't YOU tell me. After all, you have all the AMPS archives.
This info is in Will's 1M-word grate parasitics debate archive.
>
>Of course, perhaps I should ask Tom for the full quote in context. I don't
>want the "edited" version that could be provided from someone other than
>Tom.
>
Tom is quite unlikely to discuss it in any way.
>>
>>> And if it was series resonance so what? The odds of it being at EXACTLY
the
>>> same resonant frequency as that of a tube's anode circuitry are pretty slim
>>> particularly in a good amplifier design.
>>>
>> To produce high voltages, the resonance can not be on the parasitic freq.
>
>Well, gee, Rich.
If you bring Jesus Christ into this thread, I'm outta here, Jon. No
foolin'.
>Let's see...If a tube is going to oscillate, it will
>oscillate at or near the resonant frequency of the anode.
At is ok.
> If the tune cap
>has no resonance it will look like pretty much a very low impedance to
>ground to VHF energy.
Amen
>Therefore, VHF energy will never reach the
>bandswitch. We've pointed this out to you before, but you always bring up
>the resonance in the cap.
True. The Tune-C only acts as a Z-step up transformer when it is
slightly off resonance. In the great debate archive, there is an example
that illustrates what seems to be taking place across open contacts in
bandswitches during a parasitic event. If you are interested, I can
describe how to find it.
>
>So, at resonance, the cap would look like something other than a low
>impedance to any energy at the frequency of resonance. However, at any
>other frequency, it still looks like it's low impedance.
With one L network, Z can be stepped up >10,000 times. An L network is
never ever resonant.
>
>Therefore, in order for the VHF energy to make it to the bandswitch, the cap
>has to be resonant at the anode resonant frequency.
no The cap must be resonant either slightly above or slightly below the
anode res. freq.
>And I believe that
>would be a parallel resonance no a series resonance (I forget).
a nearby series.resonance would fill the bill.
>
>So if the resonant frequency of the cap is different than the resonant
>frequency of the anode, how does the VHF energy make it to the bandswitch?
When the Tune-C resonance is nearby it acts like a Z step-up L-network.
Dead on the resonance, the Tune-C is a virtual short and the parasitic is
a dead duck. .
>
later, Jon.
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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