[sdiy] diy HV probe?

[Ingo Debus]

Am Sonntag, 27.06.04 um 21:15 Uhr schrieb R. D. Davis:

>   It's also possibly not a good idea to use it to measure the
> output of the multiplier with, but rather the lower (3KV to 5KV or so)
> outputs of the HV supply with before the multiplier; either way,
> playing with high voltages can be dangerous.
>
> All that having been said, you might be able to do with out building
> that.  Are there any signs of HV being present, such as a staticky
> sound when powering the 'scope on or off, or will a piece of paper
> stick to the CRT surface?  What about the low voltage circuitry in the
> power supply, such as the HV oscillator?

5kV on the *low* output? Staticky sound? Sticking piece of paper? What 
voltage is used in these scopes?

My humble Hameg has "only"  2kV of high voltage. No staticky sound like 
when powering up or down a computer monitor, and no sticking of 
anything to the screen.

To the original poster (the one whose scope broke): on my scope the 
reason for a too low HV was the mains transformer. The AC voltage of 
secondary winding for the HV supply is much lower than the HV itself, 
about 500 volts AC. Perhaps it's easier to measure this.

I do have an old voltmeter with a 6000V DC range. I never touched the 
probes when doing these measurements, I clipped them to the scope, then 
stepped back and inserted the scope's mains plug. Still scary when it 
shows 2000 volts..

Ingo