By digital codecs MC145026/MC145027 and tiny radio transceivers M303S/M303R digital encoding and decoding switch composed as shown below

Press the transmitter button to SA, the circuit is energized the work of a serial encoded signal output from the MC145026 to 15 feet, prepared by the transmitter module M303S shoot out. M303R in the receiver module receiving circuit to receive encoded signals demodulated given away after the decoder MC145027, when the encoder and decoder when the address exactly the same code, MC145027 effective instruction decoding a high-side output pulse signal turns on transistor VT , relay drivers, complete the switch control function.