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Old 08-26-2010, 03:14 PM
Hampshire Hampshire is offline
Join Date: Jan 2003
Location: Minneapolis
Posts: 10,571
Troubleshooting static on phone lines

The past few days we've been getting some bad static on our home phone lines.
We've got phone service through Comcast so basically you have coax running into your house attached to a modem. From the modem you run a phone cord to a phone wall jack which is interconnected to all the wall jacks in the house.
Comcast had me unplug the phone line from the modem and attach a phone directly into the modem. Ta-da, no static. So their conclusion is that I have bad wiring in the house somewhere.
Does wiring just suddenly go bad?
I tried a few things. Unplugged two other phones from their outlets. Tried the good phone in an outlet (one of 6). Still got static.
Replaced the wire running from the modem to the wall jack. Still got static.
Ran a longer wire from the modem to a phone jack in another room. Still got static. Tried plugging the phone directly into the modem again. No static.
Any ideas where to troubleshoot next?
Old 08-26-2010, 04:20 PM
beowulff beowulff is online now
Join Date: May 2001
Location: Scottsdale, more-or-less
Posts: 15,088
Check every connection, and double-check the ones outside.
Unplug all phones but one.
Look for corrosion on any screw terminals.
Old 08-26-2010, 04:36 PM
johnpost johnpost is offline
Join Date: Jul 2009
Posts: 12,056
your in house network, wiring that connects jack from output of modem to jacks in the rest of the house, likely has a bad connection. look in the boxes of that wiring, while not connected to modem, for loose wires/screws.
Old 08-27-2010, 08:47 AM
racer72 racer72 is offline
Charter Member
Join Date: Mar 2002
Location: Auburn, WA
Posts: 6,092
I had the same problem when I moved into my current house. Instead of dealing with the wiring in the house, I dumped all the hard wired phones and bought a cordless phone system. 1 phone in a master base (it is plugged into the modem) and 4 other phones in remote bases. The only requirement is having an electrical outlet to power the chargers. Problem solved and I can put a phone anywhere in the house, I'm not limited to locations with phone jacks.
Old 08-27-2010, 10:02 AM
Mk VII Mk VII is offline
Join Date: Nov 2003
Location: England
Posts: 2,736
Could be your wiring has been nibbled by rodents and the insulation has decided to break down. Or it's run under a carpet and someone has nailed through it. Or constant walking over it under the carpet has worn it away ...
Old 08-27-2010, 11:00 AM
aceplace57 aceplace57 is offline
Join Date: Oct 2009
Location: CentralArkansas
Posts: 22,978
I had static on my line about 10 years ago. It was disconnecting my dial up.

I still pay a few bucks a month for the phone company's Inside Wire Maintenance Plan.

I called and they sent someone. They couldn't find anything wrong. So, the service tech went to the neighborhood switch box (2 blocks from my house) and moved me to another circuit.

Problem solved.

Last edited by aceplace57; 08-27-2010 at 11:01 AM.
Old 08-27-2010, 11:20 AM
Mk VII Mk VII is offline
Join Date: Nov 2003
Location: England
Posts: 2,736
He shouldn't do that (tho' many do, to make a quick fix) otherwise they end up with numerous faulty bar pairs that no one has ever bothered to fix properly, and when they run out suddenly there's no quick fixes anymore.
Old 08-27-2010, 12:31 PM
johnpost johnpost is offline
Join Date: Jul 2009
Posts: 12,056
Originally Posted by Hampshire View Post
Does wiring just suddenly go bad?Any ideas where to troubleshoot next?
What you have done using two cords to feed home wiring and feeding the modem output into two jacks was good troubleshooting. To have that happen and have the phone wiring be good would be unlikely.

Visually check phone wiring for damage and with the phone wiring disconnected from the modem check inside the jack boxes for a loose wire or screw.

reconnect wiring to modem and test.

if you still have static next would be to electrically test the home phone wiring. this would be done with the home phone wiring disconnected from the modem. you would test at each jack box to see that no wire is electrically connected to another wire. you would check that each wire is continuous through out. you would do this test with an ohm meter. do you have one and know how to use it?


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