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Michael A. Terrell Michael A. Terrell is offline
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Default old trusty DVM just died. Recommendations for a replacement?

rex wrote:

I agree on Fluke robustness. Pretty much the same story with my 8520A
bench meter.

I wanted to make my own high voltage probe. At a flea market I had
aquired some glass encapsulated resistors that were multi-megohm. I
thought they would be perfect for my probe divider, so I built one in a
plastic tube. Tried it at some hundreds of volts and it seemed to be
working as expected. I applied it to something like 1700 V. The tube
was clear plastic, and to my horror the resistor lit up with plasma and
ugly clicking noises came out of the meter. Looking at the meter, the
fluke display had switched to Klingon or something. Expecting disaster,
I power cycled the Fluke. It came back to life and was fine.

That resistor still baffles me. As I said it was in a glass tube and was
at least an inch long. It looked perfect for HV. My guess is that it was
filled with some gas to deliberatly short itself at some voltage in the
low KV range.



Did you clean all body oil and other contamanints from the resistor
before you used it? A single fingerprint on a one inch glass HV
resistor could cause arc over, and for it to self destruct.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida