Found in a Popular Electronics from the 90s, this circuit can be used as an electrifier. T1 can be an old TV fly back transformer or an ignition coil.
This circuit for telecommunications was found in a 1987 documentation. Connected to the...
This circuit is from a 1966 American documentation. The circuit uses a photo-FET, an unusual...
Currents up to 1.5 A can be regulated with this circuit. The resistor R that determines the...