Simple home made car alarm

dori2o

Could anyone point me in the right direction.

I'm looking to make a homemade simple car alarm system. Simple motion and voltage drop detection.

Could anyone provide details of where I might be able to obtain plans for such a project?

sharkie

elektor or everyday electronics etc.

Or in google type the words CAR ALARM KIT

or try cricklewoods electronics or maplin.


you do realize a voltage drop sensor and the alarm are two different projects/pcb's/circuits/things that if you are lucky may reside on the same circuit board but more often do not.

kwikbreaks

Your neighbours are going to love you when the damned thing goes off a 2 in the morning for no reason.

Factory fitted alarms are bad enough, the aftermarket are ones dire, I hate to think how many false alarms a homebrew one is going to generate.

googler

kwikbreaks wrote: »

Your neighbours are going to love you when the damned thing goes off a 2 in the morning for no reason.

Factory fitted alarms are bad enough, the aftermarket are ones dire, I hate to think how many false alarms a homebrew one is going to generate.

This crossed my mind too.

DatabaseError

you do know you can buy a complete alarm system for around £20 on ebay? Not gonna be approved, so going to make no difference to your insurance costs, but neither would your homemade one..

sharkie

firstly you are both thinking of ultrasonic or vibration sensitive alarms.

The vast majority of people whom build these know (a) how they work and are able modify them (b) savvy enough to position them correctly (c) test them thoroughly.

The only real downside in home built alarms is that a pretty moulded box is had to get, and mounting the circuit takes much more effort.

Generally speaking, unless you are paying big £, manufactured alarms do not have the quality or sophistication of built ones. The other psychological advantage: the more you pay, the safer you feel and more sophisticated you think the alarm is. In practice this can be very misleading as the build, component quality and design are often put under price restraint, causing the poorer quality alarms to be triggered all hours of the day, as apparently you are used to.

The other aspect is that if you install a diy alarm in the car, often the insurance company will not give you discount, and in some case may even invalidate the insurance, or make the premiums higher.

The type mentioned above and below is especially stable, but the wiring it in is not as easy as the types that always go off.


http://www.quasarelectronics.com/velleman/k3504-car-alarm-kit.htm

Col7777

A mate of mine rigged up an ant-theft system in case anyone tried to steal his car.
What happens is if anyone comes down his path very large floodlights come on and almost blind them. If they as much as go near his car 2 rockets mounted on either side of the house fire in to the air that have nets attached, so they trap the would be thief.
As the nets hit the ground they trigger off an emergency phone to alert the police, during this time another canon mounted on the roof fires a spray of illuminant paint over the would be thief in case he does manage to break free he/she is easily detected.

Any way the other day the police arrested his postman who was delivering his Christmas cards.