Jon,
I do not think that you were far off track. Everyone learns in basic
electronics AC theory that it is expected that you will have voltages that are
higher than the AC voltage applied in any resonant circuit. This can be
verified with the formula Z= sqrt of r squared + (Xl - Xc) squared. Then use
ohms law from there. The only issue is that unless you are dealing with a
loaded Q that is greater than 100 it does not come any where near double the
DC plate voltage.
The AC voltage, or more appropriately "DC voltage at an AC rate" coming
from the tube can never exceed the DC voltage at the plate. But resonant/tuned
circuits are what makes things like tesla coils work!
-- Buddy
Jon Ogden wrote:
> >>>I remember reading that one
> >>>must accept the fact that the AC voltage across the tune C can end up
> >>>being twice that of the plate voltage.
>
> Well, I must be getting old because I am losing my memory. After asking
> this question initially and getting back responses to it, I went back and
> re-read the section in the ARRL handbook.
>
> The handbook was correct as everyone told me: With a blocking cap the
> peak RF voltage is equal to the DC plate voltage. It's without a
> blocking cap that you get the twice the DC voltage at peak. So I
> remembered incorrectly!
>
> Just gettin' old...
>
> 73,
>
> Jon
> KE9NA
>
> --------------------------------------------------------------------------
> Jon Ogden
>
> jono@enteract.com
> www.qsl.net/ke9na
>
> "A life lived in fear is a life half lived."
>
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