-=> Quoting Dave Garland to Bob Gearhart on PHONE LINES<=-
 BG>  Yellow is ground and black is for AC.. Explanation:  When the princess
 DG> This may have been true at one point.  These days, however, the codes
 DG> are: 
 DG> Cable       Pair         Tip        Ring(Ground)
 DG> ----------- ----         -----      ------------
 DG> 2 pairs       1          Green        Red
 DG> 2          Black        Yellow
 The above is for 4 wire house wiring to jacks, he asked what it was
 used for.  Originally wiring was only 3 wire with tip/ring/ground. It
 wasn't until the princess phone and its little light bulbs that the
 black wire was added to carry the on premise transformers ac to power
 the bulb.  It is used as a second pair today in some cases but that was
 not its original use.  The twisting of that pair is different than the
 tip/ring pair to keep ac hum to a minimum.
 DG> 4 pairs       1          White        Blue
 DG> 2          White        Orange
 DG> 3          White        Green
 DG> 4          White        Brown
 DG> (from: USWest Communications, "Telephone Inside Wiring Standards")
 The telephone code for the numerical designation of color coded cabling
    tip colors: white 1, red    2, black 3, yellow 4, violet 5
   ring colors: blue  1, orange 2, green 3, brown  4, slate  5
   The first five pair 1 - 5, are the five ring colors twisted with the
   first tip color white, next five 6 - 10, are the five ring colors
   twisted with the second tip color red, and so on until you reach 25.
   In a cable larger than 25 pairs, each group of 25 pairs is wrapped
   with a binder of plastic or cloth strips colored in a similar manner.
   On some inside plant wiring, usually in large businesses, the ring
   wire will have smaller dabs of tip color to indicate its matching
   tip, and the tip will have dabs of ring color to indicate its
   matching ring.
   Tip top, ring right old axioms used by telephone people to determine
   where on a termination block the individual wires go. 
 DG> Then there were the party lines with 8 parties and coded rings.. "two
 DG> short rings, pick it up, that's for us", "a long and a short, pick it
 DG> up quietly and listen, that's for the scandalous Miz Parker".  When I
 DG> was a kid, I had a high-impedance amplifier hooked up so I could
 DG> listen in comfortably without the clicks and breathing noises that so
 DG> often gave less techno-savvy listeners away :) 
 DG> -Dave
 Tsk, Tsk.... :)  I made a lot of money in the early sixties rewiring
 telephone plant as a contractor to the small independent companies on
 my Saturdays off.  Thats when the FCC mandated no more than 4 parties
 to a line in many rural telephone offices. This was before color coded
 cable, back when a splicer had to know how to splice and wipe lead.
 Bob..
--- Blue Wave v2.12 [NR]
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