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 voltage-controlled oscillator or VCO has rectangular and triangular signal outputs. The...
This circuit was obtained from a 1965 Radio Electronics. The semiconductors used admit modern...
This Hall sensor circuit is intended to isolate an audio signal applied through a coil. The...