Found in Philips' 1967 documentation, this circuit makes use of period components. The SCR can be of any type, depending on the power of the controlled load.
This TTL circuit was found in the December 1990 issue of Radio Electronics magazine. The circuit has...
Found in an Electronics World of 1968 this circuit can use any SCR and diodes depending on the...
Placed near a telegraphic transmitter (CW) and with a small antenna or pickup, it reproduces the...