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alarm with infrared remote

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New Member
I built this circuit recently and decided to do a rough schematic and post it here.It is a car alarm.You need to mount the sensor and led where they are visible from a window .I made the transmitter out of smt parts and mounted it in a keychain led flashlight.when you turn it on the led comes on and it waits for a signal from the sensors .If it gets a signal from a sensor it turns on a relay which I'm connecting to my horn.You have to have line of sight and be pretty close to control it .

Could anyone suggest some sensors?

I made my own vibration sensor.
I took a piece of a retractable radio antenna and hooked it to one lead.
I hooked the other lead to a nail hung in the center of the antenna tube.
then I hung the whole thing so that if you park on a hill it will lean .
Sort of a wind chime crossed with a bell.
I had to use really fine motor wire with thread to support the weight.
What would be awesome is If the whole vehicle body was made into a proximity sensor.

Here is the ROUGH drawing of the schematics and the .asm files.

And thanks to Nigel for showing me how to do the infrared stuff :)
There are some connections not showing such as power and a 5v regulator but you get the idea. Don't forget when you build the transmitter the button cells have a positive shell . I assumed it was negative now I'm trying to get them in backwards.



New Member
Thanks for your idea.

I saw some laser pointers at the local dollar store for $1.
I even noticed the plastic box would make a good project box.
I see you're new so I'll say welcome to the forum.

That's what I like about the internet, people trading ideas.

Just so this post isn't completely useless I would like to mention that the transmitter by itself would make a good trick remote .You could turn off all those annoying T.V.s at the stores.

That's why I used linux lirc detector to add mute and power to the code list I got from Nigel.
You can use a universal remote and record the signal for different model of T.V. ,then figure out how to recreate it.
This was my first time etching a circuit with peroxide+hydrochloric. It worked great
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Actually, the Internet is about war =)
It started out as a DARPA project for transfering information for intercepting incoming bomber information and was funded by the governement as a fault tollerant network. Everything that came after was a 'well what else can we make it do' sort of thing. Kind of like the modern day Internet, which explains why there's so much crap.
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