Basic Circuit for Making a Car Burglar Alarm

Discover how to construct a basic circuit for a car burglar alarm in your house.

The circuit is constructed from a few simple parts, but when combined with the safety features of the automobile accessory, it shows to be completely infallible.

A clever burglar cleaning up your car's audio as you wake up is definitely not something you'll like.

The little circuit of a car burglar alarm system that is explained here may undoubtedly provide you complete peace of mind about the safety of your vehicle's components.

Why Vehicles Need a Burglar Alarm

How much do you value your car? You could argue it's a silly question, and that a car is obviously too significant for any one person.

In actuality, it serves as a vital component of existence and an asset to a lot of people

Given that modern cars are fully furnished with amenities that are on par with those found in homes, it is true that cars and houses are quite similar.

Consider a music system, for instance. It's likely that the one you have in your vehicle is far more advanced than the equipment in your house.

But did you realize that if anything's so precious to you, it may be to a lot of other people? They might be continuously lurking behind cars, grabbing your most valuable device, and running away with it.

It's true we are referring to criminals who have been carefully taught to steal pricey auto components quickly and covertly so that no one would notice.

I would like you to reconsider the prospect of installing a safety device in your car ahead of you become savvy and go shopping. A basic electronic car burglar alarm circuit would set you back only $1 and offer the equivalent degree of protection for the audio system in your vehicle or any other interior accessories as a costly system that costs $100.

In order to understand its circuit explanation, we can study this next discussion:

The Operation of This Basic Burglar Alarm

Since the negative side of the battery is connected to the car's chassis, the body or metal chassis of any motor vehicle will usually remain at the ground's voltage.

Therefore, it functions as a massive "earth" or ground and aids in absorbing all electrical disturbances. This is especially beneficial for the audio systems' ability to provide clear outputs.

Because their negative contact may be fastened right away to ground, eliminating the need for bulky wire, this also gives all electrical devices quick and simple access to the negative line.

For our existing circuit, the earthing function above works well as a pick-up point.

In essence, one of the automobile audio mechanism's mounting screws has a trigger point from the circuit tied to it.

Everything stays healthy as long as this circuit connection is maintained at its negative voltage.

In the event that a thief attempts to remove the system in question and removes the screws, the circuit will activate and the automobile horn will ring, alerting everyone nearby and you to a potential theft.

The accompanying circuit diagram for a car burglar alarm system is really straightforward and simple to comprehend. The T1 and T2 transistors are set up as current amplifiers.

T1 is prevented from conducting for as long as the connection of C1 and R1 is maintained at a ground potential (as previously mentioned).

But as soon as this electrical link is cut off from the earth potential, positive voltage floods in via C1 and causes T1 to go into the process of conduction

This instantly charges C2 and activates T2, which in turn activates the alarm system and siren.

In order to properly charge C2, C1 ensures that T1 is only permitted to conduct for a single second.

Together with R2 and R3, C2 creates a sort of short-duration timer that activates the horn for a few seconds, which is sufficient to startle the intruder and cause him to permanently depart.

Parts List