cook@sybil.cs.Buffalo.EDU (John M. Cook) (11/17/89)
Came across a question I didn't know today so I'm now asking the Net.
Does anyone know what signals run across the cable running from a
modem to a wall jack? In my case I have 6 wires, I know that 2 are
transmission lines. Can some tell me what each wire is for?
The complete problem is I need to know which line carries a
signal when the line goes Off-hook. A friend added a modem to his
computer at the office and the phone line is part of a PBX. The
problem is he is only using the two transmission wires so when he uses
the modem the light for that line doesn't lite on the phones in the
office. I need to figure out which is the third or even fourth wire
needed to tie into the PBX so we can get the lite on the phones to
work.
Thanks for any help you can provide.
John CookAIN14922@merrimack.edu (Doug Linder) (11/17/89)
I have a question in a similar vein: what kind of solutions have people come
up with for using a modem when you only have 1 phone line? Do you just use it
late at night when no one's likely to call? Do you just let people think
you're on the phone for 3 hours at a time? Can an answering machine be put in
the loop? Is there special equipment for this? Thanks in advance.
--
Douglas D. Linder, Merrimack College, N. Andover, MA
CSNET: ain14922@merrimack.edu
UUCP: {uunet,wang,ulowell}!samsung!hubdub!ain14922morrison@ug.cs.dal.ca (Brad Morrison) (11/20/89)
For most phone lines there are four wires. They are really two pairs of wires. I believe it's Black & Red, and Green & Yellow. Each pair is for a separate phone line. So, you can carry up to two separate lines from each cable (this is for a regular modular residential jack. I don't know if this applies to PBX systems or not). Hope this is of help to you. . . Brad Morrison
johnl@esegue.segue.boston.ma.us (John R. Levine) (11/21/89)
In article <1989Nov20.135228.2503@ug.cs.dal.ca> morrison@ug.cs.dal.ca.UUCP (Brad Morrison) writes: >For most phone lines there are four wires. They are really two pairs of >wires. Each pair is for a separate phone line. ... Sometimes yes, sometimes no. There are about ten different ways that a four-wire modular jack can be hooked up. The usual scheme with one phone line is RJ11. Two lines is RJ14. The original question was about a key system where there is an in-use light on the phone for each line; that takes an RJ12 or RJ13 where the third and fourth wires are for the in-use relay, in which case the center two wires (red and green) are for the phone and next two (yellow and black) are the A and A1 wires which the modem needs to short together while it's using the phone. -- John R. Levine, Segue Software, POB 349, Cambridge MA 02238, +1 617 864 9650 johnl@esegue.segue.boston.ma.us, {ima|lotus|spdcc}!esegue!johnl "Now, we are all jelly doughnuts."
jwi@cbnewsj.ATT.COM (Jim Winer @ AT&T, Middletown, NJ) (11/21/89)
In article <1989Nov20.135228.2503@ug.cs.dal.ca>, morrison@ug.cs.dal.ca (Brad Morrison) writes: > For most phone lines there are four wires. They are really two pairs of > wires. I believe it's Black & Red, and Green & Yellow. Each pair is for > a separate phone line. So, you can carry up to two separate lines from > each cable (this is for a regular modular residential jack. I don't know > if this applies to PBX systems or not). Red = tip Green = ring tip + ring = normal telephone circuit yellow = ground black = auxilliary grounding aux temporarily is used for signalling in old type key systems. Also 3 pair setups for PBX or keysystems pair 1 = analog pair 2 = digital signaling pair 3 = power or pair 1 = power pair 2 = receive analog pair 3 = transmit analog or various other arrangements depending on manufacturer Also 4 pair setups used for PBX or keysystems various arrangements depending on manufacturer In short, if you want to know the signalling setup, you need the PBX installation documentation. WARNING: some PBX setups, especially those with separate transmit and receive pairs cannot accept a standard modem. (If you can connect an answering machine directly, you can usually connect a modem.) Good Luck. Jim Winer -- The opinions expressed here are not necessarily and do not represent nor in any way imply of any other sane person and especially not employer. "My reply is that such pre-theoretical conceptual essences are often riddled with deep ambiguity and internal incoherence, despite strong convictions people have that they know what they mean." -- Aaron Sloman
cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn) (11/22/89)
In article <12219@merrimack.edu> AIN14922@merrimack.edu (Doug Linder) writes:
$ I have a question in a similar vein: what kind of solutions have people come
$up with for using a modem when you only have 1 phone line? Do you just use it
$late at night when no one's likely to call? Do you just let people think
$you're on the phone for 3 hours at a time? Can an answering machine be put in
$the loop? Is there special equipment for this? Thanks in advance.
When I'm here at university, I'm in a single room so I don't have a
roommate to worry about, so I have no problems with tying up the phone
line for hours on end. When I'm at home with Mom and Dad, I basically
a) check to make sure they're not planning to originate or receive a phone
call for a while or b) use the modem when they're out of the house.
Most or all of the people who are likely to call me know I spend a
lot of time on the modem and therefore aren't surprised if they get a
busy signal.
I know of fellow students who have two lines in their apartments, one
for phone/answering machine and the other for the modem. If you're
going to be using your modem a _lot_ and have others living with you
or are doing business out of your home or whatever, I'd recommend getting
a second phone line if it's at all possible.
--
Stephen M. Dunn cs4g6ag@maccs.dcss.mcmaster.ca
<std_disclaimer.h> = "\nI'm only an undergraduate!!!\n";
****************************************************************************
They say the best in life is free // but if you don't pay then you don't eatHoward_Reed_Johnson@cup.portal.com (11/23/89)
cook@sybil.cs.Buffalo.EDU (John M. Cook) writes <13410@eerie.acsu.Buffalo.EDU>: > A friend added a modem to his computer at the office and the phone line > is part of a PBX. The problem is he is only using the two transmission > wires so when he uses the modem the light for that line doesn't lite on > the phones in the office. johnl@esegue.segue.boston.ma.us (John R. Levine) writes <1989Nov20.200531.8246@esegue.segue.boston.ma.us>: > The original question was about a key system where there is an in-use > light on the phone for each line; that takes an RJ12 or RJ13 where the > third and fourth wires are for the in-use relay, in which case the > center two wires (red and green) are for the phone and next two (yellow > and black) are the A and A1 wires which the modem needs to short > together while it's using the phone. Most modems which support RJ-12 or RJ-13 lines accept the Hayes command AT&J1 for operating on such lines.
poffen@molehill (Russ Poffenberger) (11/28/89)
In article <1989Nov20.135228.2503@ug.cs.dal.ca> morrison@ug.cs.dal.ca.UUCP (Brad Morrison) writes: >For most phone lines there are four wires. They are really two pairs of >wires. I believe it's Black & Red, and Green & Yellow. Each pair is for Actually green & red are one phone line, and black & yellow are another. When only one phone line is in use, usually the green & red are it. Russ Poffenberger DOMAIN: poffen@sj.ate.slb.com Schlumberger Technologies UUCP: {uunet,decwrl,amdahl}!sjsca4!poffen 1601 Technology Drive CIS: 72401,276 San Jose, Ca. 95110 (408)437-5254 ------------------------- In a dictatorship, people suffer without complaining. In a democracy, people complain without suffering.