Re: found - sprague red HV capacitors

To: tesla-at-pupman-dot-com
Subject: Re: found - sprague red HV capacitors
From: "Adam" <adamsmith-at-mediaone-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Tue, 18 Apr 2000 17:14:14 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

on 4/18/00 8:54 AM, Tesla List at tesla-at-pupman-dot-com wrote:

> sprague (red colored) HV capacitors, female screw terminals in each end:
> 
> 500 pf, 30KV, 30DKT5, marked 715C-Z
> 1 inch in diameter, 1.5 inches long
> $18 each - there are 4 of these
> 
> 4700pf, 20KV, 20DKU47, marked Z5U
> 2.25 inches in diameter7/8 inch high
> $30 each, there are two of these
> 
> If anyone can find details of what these have for a dielectric, I'd
> appreciate knowing (also, post it here for others who may be considering
> these) - I did a web search and can't find anyting on these.

These are ceramic "doorknob" caps (barium titanate).  These caps are OK for
small coils, but they're lossier than plastic caps.  I've seen these
successfully paralleled for use on medium-sized coils too, but there are
better options.  

Those 500pf caps are fine for bypass caps.

-Adam