Jon
>>>Is the amplitude of a spark that is generated by hotswitching a 100W
>>>signal on the input relay really large enough to drive the tube and
>>>thereby generate a change in anode current on the output?
>>>
>>? Would you expect a change in input potential to cause a change in
>>anode current?
>
>Oh, sure. But my question is not wether or not it happens. But as Tom
>pointed out, the filter action of the input pi-network will limit the
>response of the spark pulse.
? agreed. The question is how much? Sparks contain wideband energy.
The pi tuned input is a low-pass filter with a Q of as low as 0.75 in a
stock 922. .
> Plus how large an amplitude is generated?
>Is it enough of a voltage spike to drive the amplifier into conduction?
? The 3-500Zs are already in conduction when the input relay contacts
bounce.
>And even if it is the output signal on the anode still won't be all that
>large.
? The HF signal at the anode has nothing to do with the signal that gets
fed back to the input. .
> And any anode ringing will be even less of an amplitude. Could
>that ringing of small amplitude be large enough to start an oscillation?
>I doubt it except for in perhaps the most instable of all amplifiers. I
>have no proof, but neither do you.
>
? Damped-wave anode circuit ringing has been reported by hams who have
access to spectrum analyzers. All power-grid amplifiers do it. note:
No parasitic arcing occurred during these tests.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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