bga@raspail.UUCP (Bruce Albrecht) (09/14/88)
I'd like to apologize in advance for posting this here, but I figured that this will get to a bunch of people who know the answer. Since it doesn't pertain to modems, I'd prefer an email response. Phone wire generally has 4 wires, red, green, black and yellow. What does each color wire indicate? Also, as far as I can tell, my connection from the Telco is two wires, and they are connected to the red and green wires at the entrance to my house. What, if anything, should be connected to the black (ground?) and yellow wires? Thanks, Bruce
berger@clio.las.uiuc.edu (09/17/88)
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