This is a ding dong bell circuit diagram.I have attached this circuit for my house.Even you can use this circuit as an sound generator.When we buy this circuit from the market we have to spend much money but now you can build this your self.Here I have used common Ic Ne 555 and you can operate this circuit with 9V power supply.
Note
# Build this circuit on a pcb
# use 9V power supply to power this circuit
# When you deal with 230V be careful
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