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.
The frequency generated by this circuit depends on the crystal used. Frequencies up to a few tens...
This circuit came out in a Frances Toute LÉlectronique magazine from July 1978, but can still be...
May 2017 - Mouser Electronics announced the availability of the LMX2491 a new PLL for frequencies...