Found in documentation from the 1960s, this circuit uses general purpose transistors that can still be found.
This is yet another version of the light-controlled oscillator that can be found on this website. This...
This filter operates in the “opposite” way to the previous one (CIR8814), cutting all signals...
This circuit is from a 1957 Japanese magazine, showing the use of OC19 in a high voltage inverter. The...