Slave flash (CB8700E)

This circuit was found in a Popular Electronics from the 90s. It uses a LASCR which is a photo-SCR not common today.

High Voltage Regulator (CB14440E)
This circuit was found in the 1972 RCA Power Transistor Databook. Transistors are uncommon today,...
20 W Voltage Inverter (CB19916E)
This circuit is used to light a 20 W fluorescent lamp from the 12 V of a car battery. The...
Crowbar (CB8420E)
This circuit fires by burning the fuse when the input voltage exceeds the value referenced by the zener....