"Catch the thief" sound alarm circuit
Source: InternetPublisher:无人共我 Keywords: Sound alarm circuit BSP transistor Updated: 2021/02/11
When a theft occurs, it
is also very valuable to use a circuit to repeatedly shout "Catch the thief!" to alert people and make the thief escape in a hurry. The circuit is as shown in the figure.
The circuit includes the memory "Catch the thief!" language chip KD 209H, button SB, transistor 8050, resistor, capacitor and 3V power supply.
As long as button SB is pressed, the circuit will sound "Catch the thief!" in time. You can install one and try it.
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