Found in an EEE from 1970, this circuit supplies a voltage of 12 V DC x 10 mA current from the power grid. The NOR or NAND port used is TTL.
Disabling this circuit from a 2002 documentation can only be done by pressing 4 keys in a correct...
This circuit was found in a 1979 magazine. We can use any JFET like MPF102 or BF245. The relay is 12 V...
This circuit was obtained in a 90’s documentation. The operational amplifiers are from that time....