hi
Anyone have the clap operated switch buzzer circuit using in key chain,this would be useful to find the key chain,of forget to kept..
This circuit also contains LED light also.and it would be 3v.
Why need to reinvent the wheel? Its available in chineese electronic shops for throw away prices..may be One USD. The same as you have explained in two variants. One with activation with whistling, the other with clap. Try shops in Guangzhou or Shenzhen market..
Cheers