I don't know if the ARRL or West Coast HB mention this, but when
paralleling RF capacitors
like this, try to layout so that they are physically in parallel, having
the same length of strap to each. If you put two together, make them on
a Tee shaped strap so that the inductance to each is identical. If you
put them in-line on a copper strap, then one of them will have different
RF current due to this lead length. Also, there is a higher chance of
creating multiple VHF resonant circuits within the L and C of the
blocker cap, with the in-line arrangement. This is explained in only one
text that I can remember, the Philips "Tubes for RF Heating" book, long
out of print.
73
John
K5PRO
> Message: 1
> Date: Fri, 18 Mar 2011 19:01:06 -0700
> From: Robert Harmon<k6uj@pacbell.net>
> Subject: Re: [Amps] doorknob cap suppliers ?
> Carl,
>
> I hear what you are saying on higher voltage caps and yes it is cramped, I
> checked the available room
> and there really isn't any room for adding much larger caps.
> RF Parts has some ceramic doorknobs in stock that look suitable. They are
> 2000pf at 7.5kv and they are about 7/8" in diameter. A pair of these conected
> in parallel would fit o.k.
>
> No steel or stainless, I am thinking of using 3/8" wide copper strap for the
> doorknobs. I would love to find some
> silver plated strap like the plate strap is, but maybe getting too carried
> away.
>
>
> Bob
> K6UJ
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