Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!cwcst1
From: cwcst1@unix.cis.pitt.edu (Carol Coates)
Newsgroups: sci.electronics
Subject: Car alarms
Summary: legal?
Message-ID: <109730@unix.cis.pitt.edu>
Date: 30 Mar 91 01:31:54 GMT
Followup-To: sci.electronics
Organization: undecided... well, maybe
Lines: 50


	Greetings. A friend's car-alarm was having problems and he
	had to drive several blocks (to the repair shop) with the
	siren going full-blast - no one even bother to look at him.
	
	Now, we just got a nice van (silly me, telling everyone :-)
	and I want to not only protect it but also make sure that
	when the alarm goes off, people NOTICE!

	I have a few ideas. Some are simple (maybe even some
	systems use them) and some are of unknow "legality".

	1) Use the standard alarm but instead of the siren, put
	   in a small 555-based circuit which after a pre-set
	   number of seconds will cut the power to the distributor.
	   That way, the thief thinks that the car died of it's
	   own... One could improve on that by allowing the car to
	   be started and driven for a few more seconds... then die.

	2) Use the power-locks (continuous "lock"), blast the siren
	   INSIDE the car, and cut the engine. This, of course, would 
	   be after several attempts at the keypad and/or "owner" switch. 
	   Not sure if it's legal to cause a headache to a criminal - 
	   with that wonderful judicial system of ours [gasp...puke]

	3) Cause the car to stall and blast a siren and blink the
	   ligts and ring the bells and turn on the smoke-bomb and ....
	   Also, of course, after several attempts (warnings) to disarm.

	Anyone? I'm thinking of #1 since it's not only doable but also
	has the greatest possibility of scaring the possible-thief. It
	is also not only save in case of an accidental arming but also
	legal (though I won't bet the farm on it - maybe the thief needed
	to get to a hospital for his condition, etc....)

	#2 is for those whose car has been stolen in the past - great if
	you get to watch the incident - in person... ;-)

	#3 is also doable - but the smoke bomb may be a little hard to
	control in case of an accidental "arming".... 


	Take care. Anyone have a simple design for #1. I think I saw
	it as a PLA project in some "old" book, but I'm not sure...
	
	Take care.

	P.S. Yes, our car was stolen several weeks ago - we got it back
	and the insurance paid $11,000 for it's repair. Why so much?
	Search me - the sticker price of our car was $14,500...........