>I am working on an amp with a pair of grid driven 4-400's. What size
>glitch resistor would be recommended for the plate circuit ?
1, 10 -15 0hms, 10w. vitreous enamel for up to 3kV. 2 in series for more
than 3kV or >30uF.
> Also what do you do about the screen ?
Bypass each screen pin (2 & 4)with two, different value capacitors say c.
500pF and 2500pF. This helps VHF stability. Use 800v regulated on the
screen. A zener-string shunt regulator fed through a power resistor
connected to at least a 1500v source is good.
Tuning a grid-driven amplifier is different than tuning a grid-driven
Class AB1 amplifier. Info is on my Web site.
>Also what would be good for parasitic suppressers?
>
A low VHF-Q design proivides c. 60% lower VHF gain with the tradeoff of
c. a 2% power decrease at 29MHz. Ugly resistance-wire exhibits lower
VHF-Q than beautiful silver strap. We sell low VHF-Q suppressor kits as
well as bulk materials. Info is on my Web site.
cheers, Gary
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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