Wireless remote control device using ultrasound for electrical system, has twin channel ultrasound transmitter signal from which is transmitted to bistable relay via demodulators and schmitt triggers

摘要

A twin channel ultrasound transmitter and receiver unit comprising two ultrasound receivers, demodulator and Schmitt triggers. The signals from schmitt triggers are fed to set and reset input of a flip-flop through conductors. The two outputs (O,/O) of the flip-flop are fed to the transistor pair via a serially connected resistor, and capacitor and to the transistor pair of bistable relay.