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 turns on and off from pulses applied to the CLK input. The output 0 goes to the “’1"...
Using the 555 this circuit was found in a Popular Electronics from the 90's. The circuit directly...
We found this circuit in a 1982 documentation. Its outputs must be applied to the input of an...