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From: percus@acf4.UUCP (Allon G. Percus)
Newsgroups: net.railroad
Subject: Re: Signaling on the NYC Subway
Message-ID: <5390006@acf4.UUCP>
Date: Sun, 22-Dec-85 10:37:00 EST
Article-I.D.: acf4.5390006
Posted: Sun Dec 22 10:37:00 1985
Date-Received: Wed, 25-Dec-85 00:59:37 EST
References: <699@astrovax.UUCP>
Organization: New York University
Lines: 19


   Basically, when there is a standard signal with three lights, they mean
the usual things: green -- proceed, amber -- proceed with caution
expecting more amber and red signals to come, red -- come to a full stop --
if you don't, an automatic "tripper" from underneath the signal will
force the emergency brakes on the train.
   A stack of one three-light signal on top of another means as follows:
green over green -- proceed on main track, green over yellow -- proceed
on diverging track, yellow over green -- proceed with caution on
main track, yellow over yellow -- proceed with caution on diverging
track, and red over anything OR anything over red -- come to a full stop.
           .
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        |II II|      (ARPA) percus@acf4
        |II II|       (NYU) percus.acf4
        |II II|      (UUCP) ...{allegra!ihnp4!seismo}!cmcl2!acf4!percus
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