>
>A friend of mine is working on a 2 x 8877 amplifier that
>he has setup to work on 20, 15, 10, and 6 meters. So far
>its working great on 20 thru 10, but he seems to be falling
>the victim of stray C at 50 MHz. His PI network design (Q=10)
>calls for 32 pf of tune-C, whereas he is measuring ~22pf of
>stray for each tube. Eimac specs for the 8877 suggest the plate
>C for each tube should be around 10pf plus whatever additional
>C is added by the layout, so his numbers, although perhaps
>a little on the high side, look like they are at least in the
>ball park.
>
>Can a design like this be made to work on 6 meters without
>gutting the 20 - 10 meter capability,
? Surely, provide he uses the appropriate amount of L in the tank.
>or is this an unsolvable
>problem. What about running with a higher Q (this would allow
>for a larger tune C)?
? run the Q needed to make it fly on 6m with C-Tune set at min. C.
cheers, Mike
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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