Car Headlight Alarm 5

[william121]

Hello Guyz!

First of all I am new here and I found this section to be appropriated for submitting my question.

Well, I was Investigating on Car headlight Alarm and how it should sound a buzzer when the headlights are on?

I have attached the circuit diagram as well you might wanna have a look on it.

I found this while i was searching for ideas. Now all I need is lots of suggestion from you guyz regarding to how it can be improved such as; a pnp transistor has been used can it be improved with a comparator or with any other components?

Are there any other components of this circuit which can be improved?

How can I make it smaller? I have heard about the surface mount techniques as well as Integrated circuits which can make a circuit smaller But I don't have a clue how they work in reality?.

So, I would really appreciate if you guyz could give me a helping hand please?

 

[ScottyUK]

Simple way - the headlights are generally switched on the positive side. Make a connection there. The courtesy light is usually switched on the negative side. Make a connection there. If you open the door and the lights are on the buzzer will sound. No extra components needed, just two wires.

If you have a modern car with CAN bus connections you're gonna need a lot more than a PNP transistor.

 

[IRstuff]

Is this for school?

TTFN
faq731-376

Need help writing a question or understanding a reply? forum1529

 

[william121]

^^
Nope! actually, I did diploma in electronics. so, I thought why not take help of electronics to build an alarm for my car.

 

[william121]

ScottyUK,

thanks mate, Can i have diagram for the simple circuit you mentioned here? I would make it on NI to see how it goes but I need a diagram to start with.

 

[VEBill]

Scotty, I think that your proposed circuit (assuming I understand what you're proposing) also needs a diode. Otherwise the power via the always hot dome light, through the buzzer backwards, will find ground through the cold headlights.

 

[itsmoked]

Nice catch VE1BLL.

I still like Scotty's idea, (with the diode). Very clever use of the recognized standard car setup.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[ScottyUK]

Well spotted VE1BLL. Thanks.

 

[william121]

I tried to make the proposed circuit with a diode to stop the current go backward. And this is what I come up with(Please refer to below circuit). There are two things wrong with the circuit;
1. The current is not going into the buzzer only the voltage does.
2. The current (12Amps) is flowing to the ground which it shouldn't do.

I need your help guyz as I might have put a wrong connection somewhere which is causing the circuit to flow the current to the ground.

 

[william121]

 

[waross]

Nope! actually, I did diploma in electronics. so, I thought why not take help of electronics to build an alarm for my car.

Where was that?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[william121]

In Barnsley College about year n half ago.

 

[MikeHalloran]

Just buy a nicer car and be done with it.

...


At least buy a fire extinguisher...



Mike Halloran
Pembroke Pines, FL, USA

 

[ScottyUK]

LOL. Mike, behave!

You haven't included the courtesy lamp. Hint: the switch is on the negative side of the lamp. Anyway, why do you need to monitor both headlights?

 

[itsmoked]

1) Drop the second lamp to the bottom.

2) Put the buzzer between them.

3) Put the bottom lamp switch on the right side its lamp.

4) Then run diode from left side of top lamp to buzzer.

5) From buzzer to right side of bottom lamp.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[william121]

one light is used to show the headlight is on and the other one is used just to show the engine is on. I didn't get what you trying to say here.

 

[itsmoked]

Do you understand what I wrote? Was that a cross post?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[william121]

^^^^
a cross post. & yes i did understand and i'll try to make it on multisim.

 

[william121]

I have finally managed to get it work and it’s all because of your help and support. I really appreciate your hard work and hope you will continue to help guyz like me in the future too.

 

[ScottyUK]

Excellent.