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Infrared Motion Switch needed urgently!

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New Member
Hi All

i need simple schematics to build a small infrared motion sensor, so when someone walks between a LED and the other wall, the path will be broken, and set off a buzzer.

If any of you have any plans that match this sort of descirption, or have any other questions, please reply with as much detail as possible!

Thanks in advance, :)



New Member
sensor alarm

:D hi there tim,

i had that schem of what you really want, however i've forgotten where i have filed it, what i have now is anultrasonic intruder alarm which i preferred. it sends out 40khz signal and can cover 7' x 15' tear drop-shaped area. if you like this just email me, cant post the schem here its not mine, i dont know who the author is. to avoid legal complications i can send you the schem thru email. :wink:
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