Cat5 cabling interference

[BankyEdwards]

I just ran a new phone line from the outside box to my room with cat5 cable, and am getting extreme static on the line ( a 1.5 decibal rating). I've hooked up a 1-foot line directly from the box to my phone, and got the same amount of static, so i know it's not interference with household appliances. This is my first 'do-it-yourself' wiring job, and I have no idea what to try to fix the problem. Any help would be greatly appreciated.

 

[daronwilson]

Hmm, sounds like the line is bad from the telco, at least to me. Generally static occurs when one side or both sides of the circuit gets too close to ground potential. The down and dirty test is to connect a known working phone directly to the line comming from the telco. Depending on the interface, there could be a modular jack there to plug your phone into and test. If so, and you still have noise, it is the telco's side and their responsibility. If you are dealing with an older interface that does not have a modular jack, I would disconnect any other wiring from the jack, use your short 1 foot wire and connect your working phone and test that.

I suspect you will find either another wire connected that is bad and causing the noise, or that the drop from the telco is noisey and bad.

Hope that helps. It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[rpearson]

Bad telephone line cords (from the jack to the phone)can cause some static.Try changing your line cord if nothing else resolves.

 

[Treedoc]

In addition to daronwilsons reply, if there is a modular plug in the interface for testing, unplug it and look at the copper pins inside and out. If it looks green or if it looks smoked there is a chance its trying to go open. 9 times out of ten, the tel. repair man won't hear it on the lugs he connects to. Leave him a note, It will make his day.

 

[BankyEdwards]

There isn't a plug on the outside interface to plug into for testing, but i did hook up a 1-foot cord from the posts directly to the phone, and it still got the same amount of static. All the static i'm recieving is on the cat5 line, all the phone lines in the house are fine and don't recieve any static, although they are getting a weak signal (6 decibals). I really don't know what else to try except running a phone line into my room instead of a cat5 cable, but i really would prefer the cat5. I also get some weird interference sounds in the background on occasion, modem or fax sounds. Don't know if that helps any, but i'm really stuck and don't know what to try, this being my first telephone wiring experiance.

 

[executone]

You Say <all the phone lines in the house are fine and don't recieve any static> If this is the case double check you Jack that is connected on the CAT5 cable. You could have a poor connection.
Also which cable colors are you using to connect this line? You should be using the white/blue pair.
It also sounds like your Demarc from Telco is an old carbon screw lug unit.These units go bad and cause a load on the line. Almost all local service providers will come out and install a new Demarc outside your home for free. It helps them out and you. I would call and see.

Good Luck!!

 

[BankyEdwards]

I've re-wired the jack several times all to no avail. I'm using the blue/bluewhite pair for the wiring, and i tried just touching to wires to the pins in the jack on the phone and still got the same amount of static. I'll check on the interface outside the house; does the telco have to replace it or can I buy one myself and replace it?

 

[jeffmoss26]

The telco will come and install a network interface for free. it is their responsibility since it is outside premises. jeff moss
jeffmoss26@adelphia.net

 

[jeffbouldin]

Do you have DSL? If so did the phone company install a filter on your house or send you something to plug in between your jack and phone? You could be hearing the DSL signal. If that is the case then you need to get a plug in filter for your new jack or make sure to hook up to the correct side of the DSL filter outside.

 

[BankyEdwards]

I have filters hooked up on the phone lines, but the line i ran into the house is going to be the line running into my dsl, so i can't put a jack on that. plus when i tested the line, the decibal signal was lower (1.6 decibals) so it isn't just the dsl i'm hearing because the signal would be stronger than that.

 

[daronwilson]

Ok I can't stand it any longer, what are you using to determine the level of the signal? I guess I'm just not quite sure what you are saying with the dB measurement, the noise you are hearing is 1.6 dB over the dial tone? over the silence of a terminated line?

If you are listening to the line anywhere without the DSL filter, you will most likely hear DSL signal in there.

This sounds like the kind of thing that happens to me about 5 pm on a Friday, I forget to check every detail and later find a bad wire, bad jack, bad line cord, corroded terminal, something simple. It sounds like you understand how you are doing the troubleshooting, the problem is quite likely not a 1 foot or 100 piece of Cat5.

Sometimes with paralleled stuff like this I just take all the wires off the interface, and make sure i have a good dial tone/quite line when terminated before I go any further. In your case, take everything off, put one DSL filter on and your test phone. It should be quiet, assuming that the wires and jacks and phone involved are good. If so, you start adding one circuit at a time until you locate the bad or noisey one.

Good Luck It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[jeffbouldin]

Get a double jack, jump from one jack to the other, plug your DSL filter into one and the phone into it, then your DSL modem into the other. Your phone should be quite and your DSL should be working.

Just to add something about DSL, anything you hook to the phone line that is POTS(plain old telephone service) needs a filter, that includes alarm systems. They require a special filter made for the alarm.

 

[BankyEdwards]

I've been having my isp test the signal (1.5 decibals) which indicates the strength of the signal they are getting back from my phone line. I un-hooked all the lines and then hooked up the cat5 to line only, and there was no static what-so-ever. but as soon as i hooked another line up, the cat5 line had static on it again. Could the other lines be to blame? If so, am i not going to get a good signal unless i re-wire those lines also? or can i somehow isolate the cat5 line from the other lines?

 

[BankyEdwards]

Well, i'm happy to say that i finally got it working, although i don't know why it's working now and wasn't before. I re-stripped the main line coming into the house so it wouldn't get a better connection to each post, unhooked everything, hooked it all back up, and it worked. I haven't had the line tested by my isp yet, but my speed test went from 950kbps to 1.2mbps-1.5mbps, depending on traffic and whatnot. Thanks to everyone for pitching in and helping out with this problem, it's greatly appreciated.

 

[BankyEdwards]

would*