You guys have me sitting up all night, worring about that big parasite
that's gonna latch onto my work in the next few weeks. The plate circuit
being laid out physically as we speak. The tune C is a vacuum variable,
next to the tube. But there is by design a strap and a blocking capacitor
between them. The blocker is the lowest inductance I could come up with, a
flat thing that looks like a pancake, custom made by High Energy in PA,
rated for 20KV. Low loss ceramic in it. The strap is 4 or 5 inch wide
copper. Man, I'd hate to think of building a parasitic suppressor for this
thing, that has to handle the plate current (40 Amps pulsed)
I'll be measuring the resonances there (yea, even the GDO will get fired
up). The big tetrodes have a lot of gain. The socket is really tight and
shielded, and neutralization is in the plan. Anything I'm missing?
Oh, a 5 Ohm Cesiwid (Carborundum Glo-Bar) in series with the grid. And a
100 Ohm swamping load on the grid to ground, before that 5 Ohm.
If it turns out to be eaten up with parasites I'll call parasite-control (1
(800)-stoppit), take 2 aspirin, and rest assured that Murphy Lives.
John
K5PRO
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