This transformerless 16-ohm speaker circuit was found in a Radio Electronics from October 1963. The circuit is powered by 12 V and the gain is 50 dB.
This circuit was found in an American 1980s documentation. The integrated circuit used is uncommon...
We found this circuit in a Radio Electronics magazine from June 1992. The circuit has a power...
This simple audio and RF signal tracker was found in a Japanese publication in 1967. The...