This circuit is from a Radio Electronics magazine from August 1974. It used one of the first photomultiplier tubes that was to be powered by high voltage. The power came from the mains.
This adjustable direct current source circuit uses a triac operating as a variac. The circuit is...
With the precision given by the crystal this circuit provides signals of several frequencies for the...
This amplifier allows you to recover recorded tapes from a tape player that has the mechanism in...