[comp.dcom.modems] Noise on TB 2500 in V.32 mode

jdr@sloth.mlb.semi.harris.com (Jim Ray) (12/30/90)

We have tracked down one of our current modem problems operating in v.32
mode.  Turns out to be a problem with the 100 pair cables running from 
ground floor to our computer facility.

However, one odd behavior still bothers me.  Upon termination of the
curcuit ( having the dialed into modem hang up ), I get about 1 and 1/2 pages
of garbage ( every time ).  Is this a normal result of hanging up the remote 
modem? I don't seem to have this behavior at 2400 baud and certainly don't 
have it in PEP mode.
--
Jim Ray                                Harris Semiconductor
Internet:  jdr@semi.harris.com         PO Box 883   MS 62B-022
Phone:     (407) 729-5059              Melbourne, FL  32901

dave@westmark.WESTMARK.COM (Dave Levenson) (12/30/90)

In article <1990Dec29.193657.17786@mlb.semi.harris.com>, jdr@sloth.mlb.semi.harris.com (Jim Ray) writes:
> However, one odd behavior still bothers me.  Upon termination of the
> curcuit ( having the dialed into modem hang up ), I get about 1 and 1/2 pages
> of garbage ( every time ).  Is this a normal result of hanging up the remote 
> modem? I don't seem to have this behavior at 2400 baud and certainly don't 
> have it in PEP mode.

It is certainly normal for most modems that you get a second or so
of noise when the far end disconnects.  A second or so is only a few
garbage characters at 2400 bps.  At 19,200 it could well be a page
or so of garbage.  It's a race between the receiver -- which is
trying to decode data from the noise, and the carrier detector,
which decides after a while that there's no more carrier, and that
the receiver can stop listening.
-- 
Dave Levenson			Internet: dave@westmark.com
Westmark, Inc.			UUCP: {uunet | rutgers | att}!westmark!dave
Warren, NJ, USA			AT&T Mail: !westmark!dave
[The Man in the Mooney]		Voice: 908 647 0900  Fax: 908 647 6857

larry@nstar.rn.com (Larry Snyder) (12/30/90)

jdr@sloth.mlb.semi.harris.com (Jim Ray) writes:

>However, one odd behavior still bothers me.  Upon termination of the
>curcuit ( having the dialed into modem hang up ), I get about 1 and 1/2 pages
>of garbage ( every time ).  Is this a normal result of hanging up the remote 

we get the same thing on v.32 connects between a Microcom and USR DS 
in the non MNP modes

-- 
       Larry Snyder, Northern Star Communications, Notre Dame, IN USA 
  {larry@nstar.rn.com, uunet!nstar!larry, larry%nstar@iuvax.cs.indiana.edu}
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