This vehicle immobilizer circuit is quite possibly the smallest, simplest, cheapest and easiest to make, install and operate.
Thoroughly field tested, robust and weather resistant design of vehicle immobilizer which can prevent vehicle theft even if thief has keys!
Here's the fancy, animated schematic:
These are all the electronic components required:
and these are all the mechanical components:
apart from these, a soldering iron, solder, heat source, fiberglass resin (and hardener) plus some lacquer and cleaning solvent - that is all that is required!
See http://home.clear.net.nz/pages/dandavies/index.htm for full assembly/installation details - or, alternatively you can watch this YouTube video showing the construction of a similar product which uses leaded components instead of surface-mount ones - and no PCB or diode is used either.
Simple, inexpensive vehicle immobilizer
This vehicle immobilizer circuit is quite possibly the smallest, simplest, cheapest and easiest to