... +60°CRange(Open field) 280 metersRF Frequency868MHz/433MHz/315MHzCrosstalk rate1/4,200,000,000Sound Level(typical) ... , mechanical energy is changed into electric energy. RF-transceiver of the receivers receive the wireless signals, ... the signals are right and the pairing between receiver and transmitter is successful, the music chip in ... door. Battery-free wireless doorbell with self-powered remote button