I responded to a question a few days ago about low power rf. Here is what
I've got.

We were recently visited by scum sucking rat bastards (pardon me, that
should probably be "juvenile delinquent benevolent society") who stole a CD
player out of my wifes car late at night. I have little interest in
conventional shrieker car alarms that go on and on and on if you are not
present to shut them off.  So I bought a wireless doorbell at the local
hardware store for about $20 US.

It has a receiver unit that plugs into the wall.  The tx part is the size
of a normal doorbell button and has a 12 volt alkaline battery.  It pulls
1.5mA when on. There are 8 jumpers to set the address to something
different from your neighbors if they have one too.

I wired it up to the interior light in my wifes car. If the door is opened,
the interior light comes on and it sends it's signal to the receiver
plugged in next to my bed.

The system does not like being constantly triggered; the chime stops and
starts and stutters. So I added a pic chip to pulse it every 4 seconds or
so. "Bing bong, bing bong. Load your gun, bing bong".

Aside from someone dragging the car onto a trailer and hauling it off (very
difficult considering where it gets parked), this should give some advance
warning of evil doers.  Perhaps something for Mr. Lile to consider using to
protect his car from the next set of visitors, at least until such time as
he has his TOASTMASTER ROBOCOP, MARK ONE ready to roll. "All right suckas,
put 'em up or prepare to be mowed down!"

Best regards,
Tom M.

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