This shield circuit, from a documentation from the 70s, employs an optocoupler with two SCRs to control a small load of 1.5 W.
Found in a 90s Popular Electronics, this circuit keeps an LED on when a phone is in use. Can be...
This amplifier stage, obtained in a 1980 publication, has a low input impedance and a high output...
This circuit was found in an American magazine in 1976. It doubles the frequency of TTL signals in the...