This circuit was found in an American publication in 1966. The circuit uses a general-purpose FET that admits an equivalent. The instrument is a 250 uA full-scale microammeter.
This 10-transistor radio was found in Radio Electronics magazine from December 1964. The...
This oscillator uses one of the four ports of a 74C14 integrated circuit and can generate 100 kHz...
This simple humidity alarm circuit includes a timed warning oscillator whose time is set to R4....