Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Clap activated switch using an ATmega8

I can still remember the funs and laughs of the Adam Sandler movie where there were three old ladies and a clap activated house – two claps to turn on the lamp – one clap to turn it off. Some people call it a cool way to fuel laziness but you must admit it’s handy to have. There are a lot of ways to implement this project most of them does not use microcontrollers – just flip flops and comparators. This actually limits the capabilities of the switch and makes it less flexible.

To address the need for the cool clap triggered switch without compromising on the flexibility and expandability of the system Toddy Cangica developed this microcontroller based clapper switch which uses an ATmega8 and a relay to detect claps and switch on and off an appliance. Clap generated signals are captured using a microphone, an NPN transistor is then used to amplify the signal before feeding it into the ATmega8’s ADC. The firmware was written using AVR-GCC and it dictates when the relay is activated to turn the appliance on and off.

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About Philip

San Francisco, Agusan del Sur CARAGA Region, Philippines
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  1. This project is really insecure… Working with 110/220V AC in a breadboard equals massive disaster.

    Also, look at the PCB: The relay contacts traces are way too close to the ground plane, it’s a disaster waiting to happen!

  2. If electricity scares you, then you probably shouldn’t play with it. This is obviously an experiment on workbench. The worst that could happen is you’d get zapped and/or blow a fuse. Neither is particularly disastrous.

  3. hi
    i need diagram of circuit and component

  4. ijlal husssain

    i have a question about circuit .how to connect the buzzer in the clap triggered switch

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