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 mimics the heartbeat with the softest sound played through a small speaker. The...
This circuit for 12 V x 2.2 W lamps was found in a documentation from the 70's. The circuit uses...
The LM318 is not a common component today. The circuit is suggested by National Semiconductor in...