Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

Vibrating capacitor non contact field probe in feedback loop to create a voltage follower: https://www.monroe-electronics.com/ESD/pdf/244a_m.pdf Bruce > > On 23 March 2018 at 15:12 Neville Michie wrote: > > Improvise by holding a metal disk over an electronic

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

Improvise by holding a metal disk over an electronic balance and measuring the force of attraction. Calibrate it with a lower known voltage. cheers, Neville Michie > On 23 Mar 2018, at 12:58, Dr. David Kirkby > wrote: > > On 23 March 2018 at 01:49, kc9ieq via

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

I guess I don't see what the issue is.  No, impedance is not infinate when not nulled, but this is why V supply #2 Is adjustable by whatever convenient means.  Rough adjust, connect, adjust for null, measure.  Rinse and repeat.  If it were my project, I'd just run up an HV transformer on a

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

On 23 March 2018 at 01:49, kc9ieq via volt-nuts wrote: > How about using (or building) an additional 2kV power supply and a > sensitive meter movement like a differential voltmeter, adjusting > for/measuring the null? Impedance at null will be theoretically infinate, >

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

How about using (or building) an additional 2kV power supply and a sensitive meter movement like a differential voltmeter, adjusting for/measuring the null?  Impedance at null will be theoretically infinate, current will be theoretically zero, and you can measure/monitor the voltage of your

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

On 23 March 2018 at 01:07, Bob Albert via volt-nuts wrote: > I found several electrostatic voltmeters on ebay. The brand I remember > is Sensitive Research. > Bob > So something like this?

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

How about using a high voltage probe that used to be commonly used to measure anode voltages of TV picture tubes. There were probes that had a KV meter built into the probe and there are ones that were used with VOM'S. Joe K3WRY   In a message dated 3/22/2018 8:59:08 PM Eastern Standard Time,

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

The part I struggle with is “make one” as T ohm meters are ridiculously sensitive to things like fingerprints, for example. I had a hard time just putting cables together that had the particular… I was going to say insulation, but it was more than that, basically everything is important and

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

I found several electrostatic voltmeters on ebay.  The brand I remember is Sensitive Research. Bob On Thursday, March 22, 2018, 6:00:39 PM PDT, Bob Albert via volt-nuts wrote: What about an electrostatic voltmeter?  Those have been around for decades and draw

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

What about an electrostatic voltmeter?  Those have been around for decades and draw zero static current.  You didn't indicate how accurate your measurement needs to be. I am trying to recall the maker of the unit, I think ESI but not sure. They were somewhat popular in the 1950s as I  recall

Re: [volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

Electrostatic voltmeter? Either the classical version or the modern electronic variant perhaps? Bruce > > On 23 March 2018 at 13:33 "Dr. David Kirkby" > wrote: > > I want to measure a high voltage, but put minimal load on the circuit. > Looking at

[volt-nuts] How can I make a 2000 V DC meter with an input resistance of at least 100 T ohms?

I want to measure a high voltage, but put minimal load on the circuit. Looking at the Keithley electrometers, the input resistance is at least 200 T ohms, but they tend to have a maximum of 200 V FSD. A 2000 V source, and a 200 T ohm resistor gives a current of 10 pA, which itself is easy to