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.
Found in old documentation, this circuit makes use of amplifiers of the time, uncommon today. Next...
Rumble is a low-frequency oscillation that occurs in turntables due to variations in motor speed....
This circuit was found in a Popular Electronics from the 90s. The circuit uses common components...