On/off keying — the carrier simply switches on and off to send bits. Dead simple, everywhere in the ISM bands.
A single line stuttering in fast irregular bursts (a packet).
Weather/temperature sensors, garage remotes, keyfobs, doorbells (433/315 MHz).
SPECTRA synthesises OOK / ASK in your browser, so you can watch its waterfall signature and hear it demodulated without any radio hardware.
Open the live receiver →