Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ames!mailrus!uwmcsd1!uxc!uxc.cso.uiuc.edu!clio!berger
From: berger@clio.las.uiuc.edu
Newsgroups: comp.dcom.modems
Subject: Re: Phone connections
Message-ID: <18600062@clio>
Date: 16 Sep 88 20:23:00 GMT
References: <288@raspail.UUCP>
Lines: 16
Nf-ID: #R:raspail.UUCP:288:clio:18600062:000:663
Nf-From: clio.las.uiuc.edu!berger    Sep 16 15:23:00 1988


Green and red are Tip and Ring (named after their respective
places on a plug for a plugboard type switchboard).  The yellow
and black wires have a variety of uses, depending on your local
telco.  The yellow wire was often used for party-line ringing, and
the black wire is sometimes used on ground-start phone systems.
The yellow and black may also carry Tip and Ring for a second
phone line, or an AC voltage from a transformer to light the
lamp in the Princess phone dial.

			Mike Berger
			Department of Statistics 
			Science, Technology, and Society
			University of Illinois 

			berger@clio.las.uiuc.edu
			{ihnp4 | convex | pur-ee}!uiucuxc!clio!berger