Hi guys .This is my first instructable .In this instructable I'am going to tell you how to make an easy and cheap laser tripwire. This is just a model circuit and not purposed for practical uses, although this circuit can be used for other light projects as well (with slight modifications).
Step 1: Things and Materials
Things that you'r going to need :-
1uf electrolytic capasitor
1.5V LED (any colour)
2 X 1.5V battries
3V Beep speaker
Bread board / circuit board
A transpsrant plastic box for circuit
Step 2: Assembly
Assembly Use the schematic to make the buzzer circuit an add a switch .Now put the circuit in the box. You'r alarm circuit is ready.
Step 3: Using the Tripwire
Turn the alarm switch to on and point the laser on the photoresistor. Now, if anything disturbs the laser light the alarm starts beeping. This tripwire is a basic and simple one, so when the laser light reaches the photoresistor again, the alarm stops beeping. Thanks for reading guys and please leave good comments and suggstions for improving.