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Posted By: sparky66wv DSL Question. CAT-5 or better? - 01/28/03 06:12 AM
I have a loyal customer who has recently upgraded to a Digital Subscriber Line.

Even with a line filter installed, crosstalk is a problem, and I fear it is because his lines are Quad-wire instead of UTP.

Ironically, when we built his addition, I had ran RG-6 for the purpose of cable modem, but alas, it was to no avail. The network interface is on the addition side, and replacing the phone wire will be a challenge because of it.

My ignorance is mostly to blame.

He has two phone lines on quad-wire with the DSL running piggy back on line "1".

What do I need to do?

Thanks in advance...

-Virgil

[This message has been edited by sparky66wv (edited 01-28-2003).]
Posted By: stamcon Re: DSL Question. CAT-5 or better? - 01/28/03 06:38 AM
Virgil, is the RG6 a dedicated run? I don't know if this would work, but if dedicated, could it be adapted at each end and used instead of the Cat5? Would a remote DSL modem and WiFi or powerline networking help? I don't have the answer, just suggestions.
Posted By: luciuskwok Re: DSL Question. CAT-5 or better? - 01/28/03 08:29 AM
For DSL, you should run at least CAT-3 UTP from the network interface to the DSL modem. If it were me, I would rip out all the Quad-wire and repace it with CAT-5. I would also make sure that the cable from the wall jack to the phones are UTP. You need to use UTP to avoid cross-talk. The more twists in the cable, the better the ability to reject interference.

One thing to do if they're having problems with the DSL side is to install the DSL modem near the network interface, connect it with a short run of CAT-5, and use one DSL filter at that point. You can then connect the phones downstream of that DSL filter.
Posted By: wolfdog Re: DSL Question. CAT-5 or better? - 01/28/03 03:08 PM
What you are describing is common setup for DSL add-on. Do you have the filters on the phone jacks?
The DSL is at a higher frequency and the filters block that from your phones,fax etc.
If you are talking about crosstalk on the voice lines, I don't think that is a DSL problem.

Here is a good site for DSL info.
http://www.dslreports.com/


[This message has been edited by wolfdog (edited 01-28-2003).]
Posted By: Scott35 Re: DSL Question. CAT-5 or better? - 01/28/03 03:21 PM
Virgil,

The best choice for any circuit used for connecting a computer to the telco's trunk (Inside Wiring, or Subscriber's Side of the NID) is something in the twisted pairs catagories - or use shielded cables.
This would include wiring for ADSL (common type or "flavor" of Residential Digital Subscriber Line), and Analog MODEMs.
This way, you can (try to) eliminate as much RFI / EMI from falling into the phone line circuit as possible, reduce the coupled effects of two separate phone lines in one cable, plus keep the line tuned and set at a somewhat steady value.

UTP (Unshielded Twisted Pair) cable is most convenient and requires simpler installation tasks. Common types include CAT 3 UTP and CAT 5 UTP Multi Pair Cable.

STP (Shielded Twisted Pair) is more expensive and requires more work to install.
IBM's "Type 1" is an example of STP Cable.

I won't even get into Shielded Untwisted Pair cables! [Linked Image]

Now for a few "...,But" examples!

I have seen a couple successful ADSL setups, where the "older" 4 Conductor "JK" type cable was used between the NID and the Brouter (Bridge Router - Proper name for what has become an Oxy-Moron slang term "DSL MODEM").
Having only seen about 30 minutes of Browsing time across these connections, they did manage well (don't know if the throughput died after I left, or not!).

The most significant reasons why these setups were successful are:
* Short Distance From NID To DSE (Brouter),
* No Analog Devices Coupled To The Line (via the filters normally included with DSL packages - used to connect stuff like fax machines and regular telephone sets to the circuit with the DSL connection),
* No Visible Signs Of HAM Radio Operators In Immediate Area / No Sign Of "Big or Small Yagi's" in neighbor's yards (didn't see any large HF / VHF / UHF Antennas masted atop towers),
* Relatively Decent Electrical Appliances And Circuitry.

A few things to consider would be:
  • What type of interference is falling onto the telephone line circuit,
  • How intense the noise is,
  • What Analog stuff is connected to the DSL circuit,
    and probably the most important;
  • Does the noise come in on the Telco's Trunk, meaning does the noise originate on the telco side of the NID.


As mentioned before, try relocating the DSE closer to the NID, then see what the results are.

Check around for crappy connections on anything possible (POTS circuits and AC Power circuits).

Also remember that each Passive device connected to the POTS circuit will affect the signal's power - and can bring in noise (or even create noise) if not correctly designed or connected.

I'll add more later if you like - and if you can add a little more info, that would be cool!
[Linked Image]

Scott35 S.E.T.

p.s. edited to fix spell-eeng again!

[This message has been edited by Scott35 (edited 01-28-2003).]
Posted By: strangedog Re: DSL Question. CAT-5 or better? - 01/28/03 04:15 PM
Before you rip out everyting try this:

Split off all other lines at the network interface from the run that feeds the DSL 'Modem'. Place a filter on all the other lines right there. If a phone shares the "home run" to the DSL Modem place a filter at that point as well.

Plan B is to pull a dedicated cat 5 Line from the network interface to the DSL 'Modem'. Again place the filter at the network interface rather than letting the DSL signal run throuout the house.

Plan C involves locating the modem on a shelf near the network interface and using something like this powerplug network to distribute the signal. You could locate a router next to the modem and use the powerplug bridge to distribute the net to the entire house, or you could place the bridge between the modem and computer.

Let us know how it works out.

PS I reccomend a router for all DSL applications, the software provided by your telco for PPPOE is crap (PPPOE is the protocal used in DSL)
Posted By: ThinkGood Re: DSL Question. CAT-5 or better? - 01/29/03 12:19 AM
Since we're on the subject of eliminating interference from telephone lines, http://www.sandman.com/bulletin.html has some good suggestions.
Posted By: George Re: DSL Question. CAT-5 or better? - 01/29/03 02:15 AM
As I recall, the phone company came out and did something to the line near my house when we got DSL. The phone company might have messed something up.

If you turn the DSL modem off and still get cross talk, the DSL is not the problem. (DSL should cause line noise not cross talk.

I would test the line where the phone comes into the house. Our phone box has test jacks in it for each line. With 2 phones you can test for line noise on the Phone company side.
Posted By: stamcon Re: DSL Question. CAT-5 or better? - 01/29/03 02:46 AM
George, this might be what the phone company did with your line. My line had a load coil on it and they had to remove it.

(From dslreports.com)
"A load coil is an inductor placed on the local loop by the phone company, they are placed starting at 3000 feet in 6000 feet intervals to suppress exactly the signal that DSL modems need to transmit high speed data on -- high frequency. The effect of a load coil is similar, from the perspective of the DSL equipment, to adding 20k feet to the line length. No DSL equipment now works through load coils. A Load coil is the major source of DSL Disappointment during the installation phase of DSL.
Here is a good site on load coils, and this one as well www.gyrene.com/loadcoils.htm
Posted By: Bjarney Re: DSL Question. CAT-5 or better? - 01/29/03 03:40 AM
Cat. 3 unshielded cable should be fine—it's rated for 10Mb/s and residential ADSL is ~1Mb/s.

I’d try temporarily running cat. 3 {or 5 but that should be overkill} across the floor between rooms and see if that fixes the problem before I’d attempt tearing out or replacing anything.

The signal gets far more abuse between central office and subscriber before it sees customer-premises wiring.
Posted By: George Re: DSL Question. CAT-5 or better? - 01/29/03 07:56 AM
stamcon ---

Thanks for the information.
Posted By: waymag Re: DSL Question. CAT-5 or better? - 02/01/03 04:31 AM
Hey Sparky I had a problem with my DSL like you are describing and it turned out to be the interface they put in the telephone box. I fought with the telco for months till they sent someone out who knew what was going on
Posted By: stamcon Re: DSL Question. CAT-5 or better? - 02/01/03 07:36 AM
Waymag, if that was a little circuit board in the interface box, I was told it was there to help the telco do a remote check of line up to that box. They had to remove it from mine when I got DSL hooked up.
Posted By: sparky66wv Re: DSL Question. CAT-5 or better? - 02/01/03 06:10 PM
Being over my head, I subbed this one out to a fellow who deals with this everyday...

Thanks for all the help, tho..

-Virgil
Posted By: ThinkGood Re: DSL Question. CAT-5 or better? - 02/03/03 08:16 AM
Are outdoor telco lines of a certain Category?
Posted By: sparky66wv Re: DSL Question. CAT-5 or better? - 02/07/03 01:40 AM
Aaaaarrrggghhh!

(ahem) Ok I feel a little better now...

Too make a long story longer...

...The "other guy" was too expensive for my customer's tastes, at $71.00 per hour.

Sooo...

The house is full of daisy-chained quad wire going from junction box, to phone box, etc. ad infinitum.

The office phone jack has a two-line phone, a fax machine on line 2, and the Brouter for the ADSL.

Upon advice from "the other guy", Customer wanted me to "merely" run a short run of CAT-5 to the Junction box, which was a short 15' run, and have only line 1 and the DSL coming to the office. Me, I opted to rather run the CAT-5 all the way to the NID (50'+), and keep lines one and two as well as the ADSL, which was the original prefered option.

Customer had to go to a meeting, and we had no chance to test...

I told him three things could happen...

1) He could log in on the DSL, pick up the phone, there'd be no interference, and all is good.

2) He could log in on the DSL, pick up the phone, there would be the same interference.

If #2 occurs, I told him we'd need to:

1)Disconnect all other phones, faxes, etc. from NID and see if hum/hiss persists... Then:

If hum persists:

1) Call Telco, it's on their end.

If hum doesn't persist:

2) Replace ALL lines with CAT-5 in Star configuration (not daisy-chained).

I fear that the existing Quadwire will still bleed... The ADSL signal goes throughout every line 1 and not just the one going to the Brouter, right?

He's not happy.

[Linked Image]



[This message has been edited by sparky66wv (edited 02-06-2003).]
Posted By: strangedog Re: DSL Question. CAT-5 or better? - 02/07/03 03:59 PM
Split the lines at the NID. Seperate the rest of the house from the dedicated run that feeds the brouter. Bad Ascii Diagram follows.

NID
|-------------Splitter
.............../.....\
Dedicated Line... | Filter
Jack in office... | Rest of house
....Splitter .....|--------------
..../......\
Brouter | Filter
--------| Other Telephones

No Dsl signal on the old wires means no crosstalk etc [Linked Image] .

SD

[This message has been edited by strangedog (edited 02-07-2003).]
Posted By: tsolanto Re: DSL Question. CAT-5 or better? - 02/09/03 06:27 PM
D.S.L Damn Stupid Lie.... Get Cable
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