>Lesson 2 is discharge caps with an appropriate
>wattage and resistance resistor.

<VBG> My father used to do the same sort of thing with the old professional
photographic flask guns. They typically had 500uF at 500V on full output,
and I know that this could produce quite a bang if shorted accidentally.

His method of discharging was to have a nichrome heater element that was
sold as a replacement for a domestic heater, put a 4mm banana plug on each
end so he could plug it into the terminals of his Avo 8, and then could use
the voltmeter probes to go into the high voltage area safely, and watch the
voltage decreases on the meter as it discharged.

But then he would also check for what I suspect you observed, and that is
the charge stored in the die-electric deformation. He would unplug the
resistor load, and measure the voltage again, and it would creep up to
around 70-100 volts over half a minute or so. This is quite a common thing
to have happen, and is the trap for beginners whenever dealing with anything
that stores high voltage.

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