Household advance working remote control circuit-receiving circuit

Receiver circuit: The receiving circuit is shown in Figure 18-66. IC 3 is a wireless receiving component} 104 is a phase-locked loop audio decoder, and its ⑤ and
⑥ pins are connected to external resistors and capacitors to determine the center frequency of the internal voltage-controlled oscillator. Therefore, IC4 acts as a single-frequency signal detector, and the detection signal
is input from pin ③. When the input signal frequency is consistent with the center oscillation frequency, its ⑧ pin changes from high level to low level. The center frequency of IC4
is consistent with the modulation frequency of the transmitter. At this time, press the transmitter button S1, the ⑧ pin of IC4 becomes low level , the relay K is electrically closed, the normally open contact K is closed, and XS1 is turned on , XS2 power socket. Half an hour before leaving work, just press Sl to connect the parallel power sockets of XS1 and XS2 (several more sockets can be connected in parallel as needed). Achieve long-distance remote control of home appliances. 3) Power supply: The DC stabilized power supply circuit can output 12V and 9V     respectively via transformer, bridge rectifier, filter, and three-terminal voltage stabilizing blocks 7812 and 7809 to supply power to the receiving circuit . The transmitter power supply can be powered by IZV dry batteries.