Re: vibrating capacitor Electrometer design (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 12 Jul 2004 09:37:46 -0700
From: Ed Phillips <evp@xxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: vibrating capacitor Electrometer design (fwd)

"Hi Ed,
If you bought the Amateur Scientist CD set, please look at the Oct. 1965
issue. Here a capacitor was made with a vibrating plate, so any charge
is
converted to an AC voltage, by q = CV, where C varies with time.

Am bot sure how the charge can be separated from the drive signal with a
varicap.
-Dave D."

	I'll take a look at the CD (or the original magazine if I can dig it
out of the archives).  My question really referred to a field mill
rather than an electrometer but maybe there's no distinction.  I'll have
to think about that.

	As for the varicaps, I suspect a balanced quad might be made cancel the
drive signal but haven 't tried it.  Key word is balanced and I don't
know how well different varicap diodes are really balanced.

Ed