wlw2286@uunet.uu.net (W.L. Ware) (09/16/90)
I've got an annoying situation on my hands. All four of my incoming
phone lines suffer from intermittent cross talk. It seems to be worse
when it is wet outside, but that is definitely not always the case.
I have had the phone company out numerous times, and they say it is
inside the house (of course.) I have had the alarm/electricians out,
they say it is the phone company (of course.) And I myself have
checked out the connections at the entrance to my house (looks fine,
infinite resistance between all eight wires, with the incoming lines
and phones disconnected.) I have also looked in the phone company's
green box, which is about ten feet from where the lines come into my
house.
The only possibilites which I can think of are:
The cables between the house and box are bad.
(Unlikely though because they are < one year old.)
One of my two line phones is causing the problem.
(This is a possibility because when things really get
bad, and voice line #1 rings so does #2 even though
there is no call on that line. But my other lines,
FAX and modem still have x-talk and they are in no
way connected to the two voice lines.)
The Telco's equipment is screwed up somewhere.
(Good possibility.)
In my basement I have two punchdown blocks, where all telephone cables
come to; it is pretty tangled. I have a network running over twisted
pair to a few rooms in the house, and one incoming line to an alarm
box far away and then comes back allowing the alarm to sieze the line.
All of the rooms in the have both voice lines, which I assume are all
wired in parallel because only to pairs are connected to each
incomming voice line, and one pair on each goes to a jack I installed.
This situation is getting annoying, and has cost me quite a bit for no
solution. Does anyone have any suggestions on how to fix it?
How would I check my phones to see if they are the problem (besides
buying new ones)?
Is there a way I can check the internal wiring for shorts?
Any help, comments or suggestions are welcome.
Thanks in Advance,
*W .L. Ware LANCEWARE SYSTEMS*
*WLW2286%ritvax.cunyvm.cuny.edu Value Added reseller*
*WLW2286%ultb.isc.rit.edu Mac and IBM Access. *john@bovine.ati.com (John Higdon) (09/17/90)
On Sep 16 at 23:01, "W.L. Ware" <ccicpg!cci632!ritcsh!ulta.rit. edu!wlw2286@uunet.uu.net> writes: > I've got an annoying situation on my hands. All four of my incoming > phone lines suffer from intermittent cross talk. It seems to be worse > when it is wet outside, but that is definitely not always the case. First, disconnect the telco circuits at the point of demark. Using a buttset or telephone with clip leads dial up a silent line on one of the lines (or call someone and tell them to be very quiet), then make a call on another with your modem (such that it connects with another) and listen for crosstalk. Do this with all appropriate combinations of lines. If you hear no crosstalk, then you may have to rewire your home with twisted pair. The fact that you measure infinite resistance between conductors points to inductive or capacitive coupling between circuits, which is what twisted pair is designed to prevent. Cleaning up your "terminal" might help also, although the rat's nest in my garage has never caused any trouble. If you hear crosstalk on the naked telco circuits then get MA back out and demonstrate. If that doesn't work, you may be forced to use my patented "Ultimate Solution". Order four new lines. When they are in and working, have the old ones disconnected. Update numbers as desired. I have had to use this approach twice in the last thirty years. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@bovine.ati.com | San Jose, CA 95150 | M o o !
ergo@ames.arc.nasa.gov (Isaac Rabinovitch) (09/19/90)
I'm no telecom expert, but I've experience with a cause of crosstalk
that nobody seems to have thought of. It affected a bunch of
residential lines that had just been installed. Turned out (according
to the guy who finally fixed it) that all the affected phone lines hat
been connected to various cable wires (go ahead and flame me, I'd like
to know the correct terminology) without reference to which twisted
pair each individual wire belonged to.
Incidentally, this was pre-breakup, and the battle between the
California PUC and Pacific Telephone (90% owned by AT&T) was still
going strong. I was told that the reason for the initial problem was
inadequate training/apprenticship for the workers who made the initial
mistake and failed to diagnose the problem (or couldn't even find my
house!). It seems likely to me now that the PUC's rate policy was
determined more by an anti-big business mentality than realistic
economics. I'm no lover of big business (especially AT&T!) myself,
but this experience raised my kneejerk reflex threshold somewhat.
ergo@netcom.uucp Isaac Rabinovitch
{apple,amdahl,claris}!netcom!ergo Silicon Valley, CA