Path: utzoo!attcan!uunet!bu.edu!att!linac!midway!gargoyle!chinet!laird
From: laird@chinet.chi.il.us (Laird J. Heal)
Newsgroups: comp.dcom.modems
Subject: Re: Line Noise Redux
Keywords: Line Noise
Message-ID: <1991Jan13.113822.13888@chinet.chi.il.us>
Date: 13 Jan 91 11:38:22 GMT
References: <59420@aurs01.UUCP> <1991Jan10.042007.4227@ims.alaska.edu> <59426@aurs01.UUCP>
Organization: Chinet - Public Access UNIX
Lines: 44

In article <59426@aurs01.UUCP> luce@aurs01.UUCP (J. Luce) writes:
>In article <1991Jan10.042007.4227@ims.alaska.edu> floyd@ims.alaska.edu (Floyd Davidson) writes:
>+In article <59420@aurs01.UUCP> luce@aurw46.UUCP (J. Luce) writes:
>+[...]
>++
>++OK, let's assume I am, is the T-clock still a valid concern. Since the
>++change of line card, the noise persists but now is of repeating
>++characters and not just a jumble of characters.
>++
>+
>+The single character being displayed sounds very much like clock
>+slips on a T1 carrier.  Usually it is '}}}}}}}'  or '{{{{{{{{'
>+I can't remember which.  With maybe on odd character at the start
>+or end of the string.
>+

>It is a CONTINUAL problem with occasional bursts AT the caller.


>I want to thank everyone for their help. I'll keep y'all updated.

I am surprised that nobody mentioned the biggest problem with the
aluminum wire.  When someone noted that an intermittent-contact
junction could cause some of the symptoms I was sure it would be
brought up.

Aluminum wire was briefly tried in houses; there are not too many
such houses left.  There was this problem with electrical fires.
It seems that the aluminum wire would expand with heat at joints,
but being less ductile than copper it was consequently not as
resiliant when it would cool.  The result was, wouldn't you know,
a gradual receding of the wire until the contact was so small as
to create a great deal of heat - enough to start a fire.

Telephone circuitry passes far less current than 120VAC, but the
ringer voltage is certainly a periodic jolt, possibly enough to
cause momentary heating.  This would induce the gradual loss of
contact which was described as a cause consistent with these
symptoms.

Take that wire to the recycling center.
-- 
Laird J. Heal                           The Usenet is dead!
Here:  laird@chinet.chi.il.us		Long Live the Usenet!