Microwave radar detection automatic light circuit (1)

The automatic light circuit produced using the RD627 microwave radar detection module will detect light as long as someone enters its
monitoring range. The light will light up. After the person leaves, the light will go out after a delay of 50 seconds. RD627 is a microwave radar detection
module     produced by Jiangnan Radio Factory in Jinhua City, Zhejiang Province. It contains components such as an oscillator, transmitter, detector, Doppler signal amplifier, limiter, and voltage-stabilized power supply. After the circuit is powered on , the microwave signal generated by the oscillator is sent to the external loop antenna through the ① and ② pins to be emitted into the space, creating a three-dimensional space microwave protection zone. When people or other objects move in the prevention area, the reflected microwave signal is still received by the loop antenna. There will be a frequency shift between this signal and the original signal. After the weak frequency shift signal is processed by the chair remover , the The Doppler signal is then amplified, and the ultra-low frequency signal corresponding to the moving target can be output at pin ⑥. This signal is buffered by Ap and sent to the comparator composed of A3 and A4 for identification. If the signal voltage is in the middle of the comparison voltage specified by Qu, then A3 and A4 will have no voltage output; when the signal is higher than the ② pin level of A3 or Lower than the level of pin ③ of A4, the diode VT can be turned on after being isolated by VDl, VD2 and current limiting by R, that is, the A-low level trigger signal is output to pin ② that constitutes the monostable trigger A5, Aj(IF, 555) flips the setting and enters the transient state. Pin ③ outputs high level, and the relay K operates and the light E lights up. After the person leaves Prevention IX, A3 and A4 have no output, and VT is cut off, with a delay of about 50 seconds. A5 is translated to the same position, K is released, and the light turns off. This circuit does not have a light control circuit, so it operates around the clock, and is suitable for situations where the power needs to be turned on even for n days.     The microwave transmitting antenna can use the ring antenna supplied by the manufacturer. If you make your own, you can use 2mm metal wire and bend it into a 20-+150mm ring shape. A2-A4 can use 1A7 41 or F006 high-gain integrated operational amplifier , and A5 is a time base integrated circuit . K is JZC-22F, DC12V small medium power electromagnetic relay . The grid machine power supply should be supplied by a regulated power supply with an output voltage of 12V.