>
>Hi Jon,
>
.......
>> I disagree, Tom. While some parasitic oscillations in amplifiers are well
>> behaved, some are not. In my 4-1000A, for the longest time while building
>> it I had a slight oscillation that I could produce every time I brought
>> the tune C to minimum. No bangs, arcs, etc.
>
>Same in amps here. When I make them oscillate, they generate
>trash and draw current. No bangs, no arcs, no bent tubes, etc.
>
>> However, at one point I was dealing with a cavity resonance. The amp was
>> stable w/o the cover. Once I put the cover on, I got a big bang and it
>> wasn't from any gassing. However, these sort of events are typically due
>> to some other problem such as a bad layout (the orignal problem in my amp)
>> or some other failure. I would venture in a "normally" working amp that
>> big bang parasitics don't occur.
>
>Ahh. But that was likely a fundamental oscillation, or a low order
>mode oscillation supported by the cavity. I can make an amp
>"explode" by making it arc on or near the fundamental. I can wipe
>out a bandswitch with a HF oscillation, or with excessive drive for
>the amount of loading used.
>
>Everyone (except Rich) knows that happens.
>
? Rich knows that all power grid tubes have finite emissive
capabilities. He also knows that when over-driven, a TL-922 can not
produce much more than 1800w-pep due the emissive limit of a 3-500Z.
Arcing the 6kV Tune-C in a 922 would undoubtedly require over 6000w.
>........
>What amazes me is how some people swallow his wild claims. PT
>Barnum was right.
>
>
>73, Tom W8JI
>w8ji@contesting.com
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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