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Help building a high voltage probe?
When experimenting with high voltage from flyback transformers etc (don't worry I know what I'm doing), it would be nice to know exactly how much voltage I'm using without exploding my multimeter.
According to these two links I found it seems fairly simple to make one, but I have some questions.
Here are the links:
http://www.kronjaeger.com/hv/hv/msr/elc/
http://www.geocities.com/CapeCanaveral/lab/5322/hvprobe.htm
1) The 2nd link says use a 1kohm resistor with a DMM so why doesn't the first link mention this? Left it out by mistake?
2) On which side of the 1kohm resistor should I put each lead from my multimeter?
3) What does the 2nd link mean by a '50uA panel meter'? A basic panel voltmeter?
I know I'm only really supposed to ask one question at a time here but any help you can give is appreciated 
The DVM has an internal resistance of about 10 megohms. The first link is using this along with the external 1 Gohm resistor to give a ratio of 100:1, so 50 kv will read 500 volts on the DVM. In the second link, a resistor is put in parallel with the meter so that there is a known resistance, and the ratio will become 1000000:1, and a voltage of 50 kv will read as 50 mv. The important thing is that the resistance of the meter is known, so that the ratio is accurate. Some DVM's have different amounts of resistance on different scales. If you use a higher value of resistance across the meter, like 1 Mohm to give a ratio of 1000:1, remember that your resistor is in parallel with the meter. So if the meter resistance is 10 Mohm, you need about 1.11 Mohm in parallel. By the way, the 2nd link says to put the 10 Mohm resistors in parallel -- they should be in series.
A 50 uA panel meter is an analog meter which is used in a lot of the old VOM's. It is sensitive to current, not voltage, so you don't need a parallel resistor. The 1Gohm resistor will give you a full-scale reading of 50 kv.
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