•  
  •  

Theft preventer alarm

This circuit utilising a 555 timer IC can be used as an alarm system to prevent the theft of your luggage, burglars breaking into your house etc. The alarms goes ON when a thin wire, usually as thin as a hair is broken.
The circuit is straightforward. It uses a 555 IC wired as an astable multivibrator to produce a tone of frequency of about 1kHz which gives out a shrill noise to scare away the burglar.
The wire used to set off the alarm can be made of a thin copper wire like SWG 36 or higher.
You can even use single strands of copper form a power cable.

The circuit operates on a wide range of voltages from 5V to 15V.
The speaker and the circuit could be housed inside a tin can with holes drilled on the speaker side for the sound to come out.

If there are any problems please contact webmaster@electronic-circuits-diagrams.com

Please share & like

Current to Voltage 4-20mA To 0-5V Conversion Sensor Module Only Module
$13.99 Current to Voltage 4-20mA To 0-5V Conversion Sensor Module Only Module picture
Current to Voltage 4-20mA Turn 0-10V Conversion Sensor Module
$14.66 Current to Voltage 4-20mA Turn 0-10V Conversion Sensor Module picture
-NOS-PLYMOUTH BISHOP W963 ¾”X30’ EPR self-amalgamating High Voltage Tape
$8.0 -NOS-PLYMOUTH BISHOP W963 ¾”X30’ EPR self-amalgamating High Voltage Tape picture
New old stock Friedland 16V 120V 10VA Low Voltage Transformer UL Listed
$15.99 New old stock Friedland 16V 120V 10VA Low Voltage Transformer UL Listed picture
Voltage Tester Kit Best Multimeter AC DC Square-Wave Output NCV Electrical NEW
$29.95 Voltage Tester Kit Best Multimeter AC DC Square-Wave Output NCV Electrical NEW picture