DSL line question-Verizon-filters [telecom]

I just replaced my Verizon modem...they sent me a new one because the old one would periodically drop signal, and had to be re-booted each time. As a followup they called my today to check that everything was OK. They ran a line test because they said they weren't seeing a perfectly good line. I disconnected everything from the demarc and the number that had been 1400, was now perfect, around 3500. Not sure what that means, but she suggested replacing all my DSL filters...they go bad she said. I have about 10 in the house, including some that serve more than one device, e.g. caller id boxes, wireless phones, answering machine, etc.

Do the filters go bad? I occasionally will hear some DSL noise when two phones are off - hook at the same time. Otherwise everything seems to work OK.

They scheduled to call back in a week to see if there's an improvement. I have some new filters, never used, that I could put in. I'd welcome any comments.

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Yes, filters can go bad. So can phones, water meters hooked to phone lines, alarm systems, etc. They may be causing problems with the DSL signalling, but still pass voice frequencies okay.

With this sort of thing, it does become the game of unhooking one thing and trying again, over and over again.

Reply to
Doug McIntyre

This has been covered in the digest before. To summarize, the best thing you can do is put 1 filter at the demark, and unless you have all home run wireing already and can isolate the jack with the modem, run a seperate wire from the demark (before the filter I just suggested, or from the unfiltered jack of the filter) direct to the modem.

At my previous house, I had done that and on a service call for an unrelated problem, the tech saw it and said "I can do better". He then replaced part of the demark with a terminal block with a filter built in.

Reply to
Rich Greenberg

On Wed, 11 Apr 2012 13:53:35 -0700, Michael wrote: .........

Put in one central filter at the demarc and run the modem directly off it. It is ridiculous to have so many separate filters.

Reply to
David Clayton

If your house has one DSL jack and one phone jack, it makes some sense to put a filter on the phone jack. This doesn't really describe most homes, though. It seems like a crazy idea to have a house with one DSL output and lots of analog outlets and put filters on all lines but one. As long as at least one of your filters is questionable, you might want to consider a DSL splitter. The phone line comes into the house, goes to the splitter, and one line goes out for DSL and all the rest of the phone wiring goes to the non-DSL output contacts.

Reply to

She's giving you the resistance measurements in kohms. 1500 kohms is a possible high resistance condition but you really need more information. Measurements are made tip-ring, tip-ground, ring-ground and a few others and the individual values are reported along with an overall characterization of the line test. Without knowing those and no apparent problems with your voice calls, I wouldn't necessarily worry about it.

Troubleshooting physical DSL trouble remotely is kind of difficult. Can she pull your DSL connection stats? Is the SNR dropping? Better to have a tech with a good meter take a look at your SNI and then at the modem jack to see what's going on.

10 splitters is kind of a high number and you're possibly seeing some reflectance. If possible I would isolate the run to your DSL modem from the other runs at the SNI and put a single filter for your phones there. There are SNI modules available that do filtering right in the SNI now. Don't know if Verizon can put one in but that would be ideal.
Reply to
Andrew Carey

Can you put one filter in near the demark, put all the phones downstream of it; and have the modem on an unfiltered branch?

Reply to
David Lesher

Yes, the filters do go bad, and if you have several voice extensions in the house the "Bridge Tap" effects of all that wire with DSL signals reflecting back can kill your data speed just as badly as it does when it's on the outside plant cabling.

I'd strongly suggest you get the Incumbent Telco to install a single Whole House DSL Filter and block the signal right there at the Demarcation Point from all but the one inside wire line and jack you will use the DSL Modem on. You'll see an even bigger speed jump because you eliminated all the stub antennas (mini bridge taps) at your end, and the speed should stay consistent. Plus you don't have to mess with all those inline filters at every phone anymore.

And if they won't (or can't) rewire the demarcation point to add the Whole House Filter, you might have to get it done by a local independent technician or DIY it. The Telco is supposed to rework a messy demarc to add a MPOE Subscriber Test Point, and a clueful installer can easily do the whole house filter at the same time. (And a lazy one will blow it off, do the bare minimum and go take a nap in his truck...)

Worst case, you can use one of those in-line filters, a pair of 6" modular line cords, a wall jack and a weatherproof box to build your own Whole House Filter if you don't want to search down the purpose-made units. Exact same function, just a different form factor.


Reply to
Bruce Bergman

The way I originally did just this (see earlier post) was that I had a multi-line NIJ (previous owner had multiple lines, I had only one) and the filters I had had 2 jacks, one filtered, one not. I removed the active line from the NIJ, plugged the filter into the NIJ, and plugged the active line into the filtered jack. Then I moved the line going to the DSL modem to another set of terminals and plugged its plug into the unfiltered jack.

BTW, I have some unneeded DSL modems. One is hard coded for BellSouth, One for Earthlink. If anyone can use one of them, its yours for whatever it would cost me to mail it to you. I also have a fancier one available. See

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and email me if interested.

Reply to
Rich Greenberg

Ron wrote in :

Lightning can also damage them and cause DSL signal degradation.

In this country (the Netherlands) the standard setup is to have a DSL/phone splitter as close to the entry point for telephony as possible and have an as short as possible cable between splitter and DSL modem, to improve DSL performance.

Koos van den Hout

Reply to
Koos van den Hout

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