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 circuit was found on a Radio Electronics of July 1984. It consists of a source with the 741...
Pulses in sequence can be generated from a clock input using the circuit shown bellow. Outputs A,...
The purpose of the circuit shown in the figure is to open and close the contacts of a relay...