This is a sound switch circuits, It will work only if the loud is overdue. Ideal for player cameras Or you can bring to other use, It’s not Fouls, such as: You may also be applied to a Burglar alarm circuit effective, or applied to the alarm clock, when it has sounds high level. It operates using electricity tool.
How it work
When you see advantages its, Might be a good idea now, come look the function of this circuit. As figure shown below. The sound signal is received by the condenser microphone Into the sound signal amplifier circuit That we choose IC op amp No. MC1458 is Dual OP Amp IC 8-DIP ST
Or other alternatives :
– LF353 is IC Dual Low-Noise JFET OPAMP 3 MHz 8-pin DIP that better quality or
– TL072ACP is IC Dual J-FET Op-Amp 8 Pin DIP that cheap and well.
Because internal structure of the two op-amps, by the shape remains the same IC-741 which the op-amp IC is timeless. Make us cost-effective, convenient and economical with space.
Come see the circuit to continue. The first op-amp IC1a is designed to the gain about ten times, the output of IC1a will entered to pass the R5 to pin 6 of IC1b, that it is designed to gain about 100 times, So the all gain of this circuit is equal to 1,000 times.
Output from IC1b be fed through C2-4.7uF to trigger at pin G of SCR1-C106D works Immediately
We use this circuit with the battery 9V, C3 provides a more stable and the C1-10uF placed to minimize disturbance, may be cause the circuit to function errors.
Build this circuit
All devices can be installed onto the PCB, as shown in Figure 2 for the wire MIC, using a shield, to prevent a noise signal, which may be make this works errors.
PCB Sound SCR Switch by IC 1458 & SCR C106D
When you installed all part correctly then to try attach the power supply to the circuit. And then use a small headphone drop across R7, if the circuit work correctly you will hear the sound from your headphone, next to connected the output to Set of flash lamp of a camera, Try to clap away from the MIC for about 2-3 inches. The flashlight works immediately but does not works Trial output terminal is connected to the light flash.
This circuit is designed primarily for use with a camera. However, you may be converted to another use, the output of the the circuit to control the relay. The sensitivity of the circuit can be increased by reducing the value of R1 down to only 22K, it would be more sensitive times.
If you are interested in this circuit.
But fear that it will not work. You can see the details of…
Elenco K36 Sound Activated Switch
Stops problems about components and The project not works.
Although the circuits are is not the same. It can produce sine wave signal as well.
Sound activated switch
SCR control circuit
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Sample and Hold by LF353+ 4066
Frost Alarm or Cold Activated Switch by IC 741