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In Reply to: RE: I would not use wire-wound resistors in grid stopper positions posted by Eli Duttman on March 03, 2017 at 22:32:34
What about a few loops of wire around a ferrite bead (i know they can be lossy at high frequency) or the old-timers trick of a wrapping the leads (or another piece of wire) of a CC resistor around the body to make a little air cored inductor in series with the resistance?
A tiny ferrite bead, just big enough to clear the socket lug, cemented to the socket's insulating base has been used. FWIW, I find that idea appealing on the (ostensibly grounded) grid of a cascode's "top" triode.
JMO, anything that truly suppresses parasitic oscillation is fine. "There's more than 1 way to skin a cat."
As politically incorrect as it is, I agree with the cat skinning and was making just that point when I questioned your insistence of a carbon comp because it was non-inductive.
It's a question of Q. Will those devices exhibit sufficient dampening at the frequencies over which the tube exhibits a tendency toward instability? I've seen transmitting tubes oscillate when the carbon comps in anode suppressors (the second device you mentioned) were replaced with spiral-wound carbon film. Depending on the tube, the circuit and the physical layout, this can be a tricky thing.
Buy Chinese. Bury freedom.
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