This shield circuit, from a documentation from the 70s, employs an optocoupler with two SCRs to control a small load of 1.5 W.
An article in Radio Electronics magazine from November 1962 taught how to connect two common...
Pressing S1 stops the circuit. This circuit was found in the October 1992 issue of Radio...
Found in 1969 Ferranti documentation, this small font is characterized by its low ripple....