Monday, November 28, 2011

Dummy Security System -Sponsored by Farnell.com

You own an old car and would like to scare off thieves? Build your own fake security system!


I got all the parts i needed from Farnell Electronics! Also check out Element14!

Parts Required (All available @Farnell.com)Check out the links next to the components!


  • resistors: 1k, 10k, 680k   Resistors
  • capacitor: 10µF radial   Capacitors
  • LED: red superbright, 5mm diameter  LEDs
  • 7555 low power timer IC  7555
  • 8-pin DIL socket for IC
  • battery clip
  • 4.5V battery box for 3 AA cells
  • stripboard: 8 rows × 16 holes  Stripboard 
This Dummy Alarm project makes an LED flash briefly once every 5 seconds to imitate the indicator light of a real alarm. The circuit is designed to use very little current to prolong battery life so that it can be left on permanently. An on/off switch is not included, but could be added if you wish.  
See the whole circuit after the break:

The components I received from Farnell

All you have to do now is soldering together the components according to this circuit:



After soldering everything together it looks like this:

You can put this little circuit into a black hobbybox, add some batteries and place it inside your car! The flashing red Led will hopefully scare off thieves and protect your precious car!
I hope you enjoyed this little and simple how to!
Come back for another tutorial on how to build a simple fast flashing Led circuit!
The parts were sponsored by Farnell.com
Thank you very much!

Here's a little video if you're interested: