This well-designed bistable circuit was found in a 1970s documentation. Transistors can be current types and germanium diodes. The voltage depends on the logic used and can be made with 5 V.
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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...