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Measuring C, HV Resistors, etc.
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From: Jim Lux [SMTP:jimlux-at-earthlink-dot-net]
Sent: Monday, June 08, 1998 10:17 AM
To: Tesla List
Subject: Re: Measuring C, HV Resistors, etc.
>
> ----------
> From: Steve Young [SMTP:youngs-at-konnections-dot-com]
> Sent: Saturday, June 06, 1998 11:42 PM
> To: Tesla List
> Subject: Measuring C, HV Resistors, etc.
>
> To all,
>
> 1) Every now and then, someone posts their need for inexpensive way to
> measure C. A great source for all sorts of parts is Tech America. Their
> catalog is available at Radio Shack, or you can get one via their website
> at www.techam-dot-com. They sell a kit (part number 990-0043) for $13 which
> lets one use a DVM to measure 2pf to 2 mf.
>
> 2) Occasionally, coilers indicate a need for HV resistors. If you don't
> mind a lot of soldering, you can make your own very cheaply. Tech
America
> sells resistors for 100 for a dollar. Use 1/2 watt resistors which have
a
> rating of 350 volts. For example, suppose you have a 20,000 ohms per
volt
> meter which can measure 5 KV, but you want to measure up to 15 KV. Just
> add 67 3 meg 1/2 watt resistors (200 meg) in series with the test lead
and
> presto, you have a 15 KV meter. Cost is 67 cents. The resistor string
> will be good for at least 23 KV and can dissapate 20+ watts. Be sure to
> arrange the ends of the resistor string so the HV doesn't flash over
> possibly resulting in a fried meter. It would help to put the string in
> oil to reduce corona and improve heat dissapation.
>
> If you don't care about the exact value of the HV resistor, then another
> easy solution is to use plastic tubing filled with tap water.
see also: http://home.earthlink-dot-net/~jimlux/hv/rwater.htm
>