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Old 18th Apr 2017, 1:08 pm   #8
MrBungle
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Join Date: Jun 2016
Location: London, UK.
Posts: 3,687
Default Re: Another FET voltmeter

Indeed. I might reinvestigate. For ref I don't have the 1M at probe tip. I have two hypotheses:

1. Fudge up on breadboard means the 1M gate resistor was shorted. This is possible as the board is a hand carved matrix board in FR4 and the meter would still work if it was shorted.
2. Transients from my HV supply. It's a hefty boost converter that can generate 600v easily if the voltage feedback network has dodgy soldering so the peak inductor voltage may be higher (1kv+)
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