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.
A fine adjustment of the output voltage of a power source is achieved with this circuit, which...
With this name, we found this electronic stethoscope with a coal microphone in a 1957 Raytheon...
This circuit can be used as a low Power audio booster for experimental projects such as radios,...