monitoring car alarm system

[hgupta1]

I often have to park my car on the street since my driveway is only wide enough for one car (and I have no garage). It has a viper alarm system, but I can't hear it from the house. Does anyone know if there is a way to wirelessly monitor my car alarm through homeseer?

 

[BraveSirRobbin]

One way which comes to mind is to have the voltage which drives the siren also trip a 12 volt coil relay and have the relay's contact closure trip a DS10a or a hacked Palm Pad remote.

 

[Rupp]

There are also add on to most alarms that offer paging solutions, vibrating remotes, etc.
http://www.ecarsecurity.com/Astra_777_p/7777.htm

 

[electron]

How is he going to interface those remotes with homeseer tho? I would defintely go the DS10A/PalmPad route as BSR mentioned, probably the easiest and cheapest.

 

[Rupp]

I guess it depends on how far he parks from his receiver. I can't get a signal from the street to my RF antenna. It should be easy to buy and extra remote and tie this into HS using the various hacking methods.

 

[hgupta1]

yeah, I want to go the cheapest route. And I have a w800 mounted pretty high, so I get good reception from the street. I am going to try the DS10a method. I'm not very familiar with relays though..where do I find a coil relay?

I wonder if there is a specific output port on my alarm system for external pagers. I don't necessarily want homeseer to be alerted everytime I lock or unlock the system.

 

[BraveSirRobbin]

yeah, I want to go the cheapest route. And I have a w800 mounted pretty high, so I get good reception from the street. I am going to try the DS10a method. I'm not very familiar with relays though..where do I find a coil relay?

I wonder if there is a specific output port on my alarm system for external pagers. I don't necessarily want homeseer to be alerted everytime I lock or unlock the system.

Might be safer to use a transistor to drive a 12 volt relay. The coil reference just meant that the relay needs to be "triggered" by a 12 volt signal driving the siren.

A couple of gotcha's here. One is I'm not sure that your siren is actually driven by a 12 volt signal. You would have to read the instructions, look at a schematic, or measure it while on to be sure.

You also might want to drive the relay with a transistor instead of directly hooking it to your speaker output as it will ad a resistance to that output (and the drive capabilities are not known of the alarm system siren output).

As far as triggering HomeSeer everytime you open and closed your car, couldn't you fix this with code (i.e. siren must have sounded for a few seconds before notification)?

Sorry, I'm not giving you anything more specific, but I have to fix my truck right now (fuel pump).

 

[jay]

If firing the relay directly from the transistor, consider bridging the coil with a power diode wired in reverse polarity - to protect the transistor from a kickback spike.

 

[BraveSirRobbin]

Good point. Look at THIS schematic towards the center (2N3904 transistor driving the relay coil). that is part of THIS How-To.