This small commercial radio for the MW band with germanium transistors was found in Japanese documentation from the 1960s. The circuit is powered by a 9 V battery and has a 455 kHz IF.
This circuit was found in a Radio Electronics from May 1965. FETs are from the time, but the...
This circuit can generate signals from 80 to 800 Hz with an amplitude of 0.3 V. We find it in a...
Because it uses TTL integrated circuits, this siren must be powered by 5 V or as indicated with D1 to...