[clue-tech] Line noise and modem hangups

[Nate Duehr]

Doug Williams wrote:
> Hello,
>  
>  I live in Centennial near the KOSI radio towers and I am having problems with line noise cutting me off when I am trying to use dial up on my computer with either SUSE or (unfortunately)Windows XP. I am using an external USR V92/fax modem I thought that it might help me connect as I have had good results with external modems before, but not now. I have talked with local side of QWest to no avail as they won't help home customers who don't use their DSL service. I was wondering if anyone else has had this issue or lives in the Centennial area near Arapahoe and Colorado Boulevard and has any suggestions short of going to DSL or a cable modem. I have tried using the rfi filters that you can get at Radio Shack with the same results. I also tried the advice of someone who works at a Radio Shack and is a SUSE user and added a shielded connector cable from my computer to the wall but still getting noise hangups.
>  
> Thank you for any help
>  
> Doug Williams

Hi Doug,

How do you know it's line noise cutting you off?  Your neighborhood 
could be serviced by a SLIC or similar muxing device, and thus 
un-friendly to analog modem service.  Can you hear KOSI on your phones?

If so, unplug ALL of your phones except the modem and see if the problem 
goes away.  Something is bringing the RF into the audio frequency range, 
and it may not be the modem -- you could have a cheap phone acting as a 
receiver.

There's a number of other things to check, but that's the simplest to 
start with.

If you have a modular demarcation point outside your home (one of the 
newer ones with an RJ11 jack) you can put a male-to-female adapter in 
and make a call right there at the outside service entrance... 
especially if you can borrow a laptop and keep the cables short (so they 
don't act as antennas).  If the problem exists even during that test, 
there's probably little you can do about it.

Qwest should at least be willing to provide you with the results of an 
automated test done by a technician at the demarc outside your home.  If 
there's no problem found, they could charge you for the site visit, though.

Other things that can be done... you can buy phone cables with ferrite 
beads already installed on each end (sometimes you see Ethernet cables 
for laptops come with these also, so they'd pass their spurious 
emissions tests).  They sometimes can help in high RF environments.

Nate