Burglar alarm



This is a very useful circuit diagram because these days there are lots of crimes in every where.So I suppose this would be an answer for your matter.Here I have used common Transistor BC107.After fixing this circuit switch on s1 and adjust R2 until the horn makes sound.Then switch off the s1 .Now if some one broke the thin wire the horn will make a sound.You can cover your garden with this circuit



Note

# Build this circuit on a PCB
#Don't supply more than 12V
# Use very thin wire to get good results

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