We found this circuit in the September 1971 Radio Electronics magazine. The SCR can be any of the 106 series and the buzzer can be replaced by a relay according to the supply voltage.
This small regulator was found in a Motorola 1968’s documentation. It is a current regulator using...
This circuit was found in a 1968 US publication. Transistors used are uncommon today. The circuit...
This electronic bait, or fish attractor, produces a sound in the water that attracts fish of...