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From: youngqd@jacobs.cs.orst.edu (Dean Youngquist)
Newsgroups: sci.electronics
Subject: IR receiver on traffic lights ?
Message-ID: <1991Apr11.211957.7309@lynx.CS.ORST.EDU>
Date: 11 Apr 91 21:19:57 GMT
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The fire trucks in my town seem to trip traffic lights to green in
their direction as they are approaching the intersection.  Does anyone
know how they do this?  I thought they might have a system using
infra-red light ?  If it is infra-red how can they work in the day-time?
Doesn't the sun put out infra-red that would interfere ?
 
Dean Youngquist                 youngqd@jacobs.cs.orst.edu
Corvallis, Oregon 97330         Tel. (503) 757-0335