This space mark demodulator for FSK signals was found in an American telecommunication documentation from the 1980s. The circuit operates with 2025 Hz and 225 Hz mark space signals.
This sensitive circuit detects the live pole of a power grid or outlet. The circuit makes use of a high...
We found this circuit in a 1980s publication for amateur radio. It consists of an audio amplifier...
This circuit uses a General Electric coupler from the time of the publication in the 1980s....