A Variable DC Power Supply is one of the most useful tools on the electronics hobbyist’s workbench. This circuit is not an absolute novelty, but it is simple, reliable, “rugged” and short-proof, featuring variable voltage up to 24V and variable current limiting up to 2A. Well suited to supply the circuits shown in this website. [...]

Ahigh voltage power supply is a very useful source which can be effectively used in many applications like biasing of gas-discharge tubes and radiation detectors etc. Such a power supply could also be used for protection of property by electric charging of fences. Here the current requirement is of the order of a few microamps.
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The circuit has an output filter consisting of a 100k resistor and a .22 uF capacitor and a typical experiment will have additional capacitance across the chamber, too. To get rid of the last bit of wander as the circuit pulses, increase the 100k to 10 megohm since ion chambers don’t draw significant current. [...]