This circuit was found in the April 1971 Radio Electronics magazine. It uses common transistors and can be adapted to use an LED or audible indicator instead of a light bulb.
n be assembled with BC558 transistors for low power transistors and a BD136 for the output. The...
This circuit, found in 1980s documentation, produces a rectangular signal of the same frequency as the...
This mixer with few components can be tried by the reader who needs this circuit, but who does not...