Loading...
Schematic Circuits

Clap Switch

The operation is simple. Clap and the lamp turns on. Clap again and it turns off.

The electret microphone picks up the sound of your claps, coughs, and the sound of that book knocked off the table. It produces a small electrical signal which is amplified by the succeeding transistor stage. Two transistors cross connected as a bistable multivibrator change state at each signal. One of these transistors drives a heavier transistor which controls a lamp.

I built my prototype on a cardboard cover from an old notebook. Punched holes using dividers and placed the components down flat. It might look neater if you draw the circuit diagram on to the board before you begin. A photo is included below. The components are from my junk box and I found that it works even if you omit that 4.7 Megohm resistor. Your results may vary.

The transistor types are not critical and any n-p-n silicon transistors should work.

Sound Clap operated switch with transistor 78C5Z.gif

Source: http://saint.419.removed.us 


Keywords : Clap, Switch
Writer : delon  |
2 Feb 2011 Wed   
|  16.625 Views
No Comments
Write Comment
Your Name
Email
You are writing as anonymous comment, if you are a member please login.