Radio detection circuit diagram

It's just a radio detection circuit that detects the radio wave signal of the corresponding frequency and uses IC1 to determine the frequency and then triggers IC2 to broadcast the corresponding sound.

Y1 is a pyroelectric infrared sensor. The power supply provides a stable operating voltage to Y1 through R1, C2, and C3. C4 filters out high-frequency noise. The signal output by Y1 (if there is someone or animal activity in front of the sensor) is sent to pin 14 of IC1 through R7. . The circuit composed of IC1 and peripheral resistors and capacitors amplifies, shapes, and delays the signal. It outputs a pulse signal from pin 2 and triggers the music storage chip IC2 through R13. The dog barking signal output by IC2 passes through R15, VT1, and VT2. Amplify, drive speaker BL to produce sound, and inductor coil L1 plays the role of impedance matching.