Re: Slightly off subject request for identification (fwd)

---------- Forwarded message ----------
Date: Thu, 16 Jul 1998 13:27:15 -0400
From: "Mark S. Rzeszotarski, Ph.D." <msr7-at-po.cwru.edu>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Slightly off subject request for identification (fwd)

Hello All:
Russ said in part:
>  He has a tube(I >would describe it as a diode as it has only two pins)
that is
>cylindrical with a diameter of approximately 2" and length of 6".  One
>pin on each end.  This is stamped in the metal on one end: VC50-20.
        It is a vacuum capacitor.  They were made by Jennings and Eimac to
name a few.  I think Jennings used the VC50-20 nomenclature if memory serves
me.  Typical values are in the 10-100 pF range with voltage ratings in the
kilovolt range.  The Jennings ones are usually made of copper, Eimac used
other materials in the ones I have seen.  They can be used in tube coils as
they are low loss (vacuum).  I have also heard of a few people who used them
as experimental spark gaps, although they foul after a while (quiet though).
I have a variety of sizes up to the 6" length you observed.
Mark S. Rzeszotarski, Ph.D.
Mark S. Rzeszotarski, Ph.D., Senior Physicist, Radiology Dept.
The Mt. Sinai Medical Center, Cleveland, Ohio 44106
Assistant Professor, Case Western Reserve University
Departments of Radiology and Biomedical Engineering
Voice:216-421-4689  FAX:216-421-5343  E-mail:msr7-at-po.cwru.edu