Operational Amplifier with Push pull circuit (PNP and NPN) with a touch switch.

Here the purpose is to build a fading siren device with One weak Oscillator (0.02 uf and 0.01 uf capacitor in Parallel.) and a single Op operational amplifier.

The speakers so you can hear the DC circuit. I am using a touch switch with moisture to gradually decrease the voltage and current to the Op-amp and the two transistors.

If you put your finger on the touch switch it reduces the current flowing across the Op-amp and the PNP and NPN transistors. This shuts off the entire circuit as shown in the video.

The frequency at the highest is 1.1-1.2 kHz. It rapidly drops as moisture leaves the touch switch.

Thank you for watching.
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