DSL disconnection problem

" snipped-for-privacy@yahoo.com" hath wroth:

Sure. It's a very common problem caused by improper installation of the DSL splitter or DSL microfilters. My guess(tm) is that there is an instrument somewhere in the house, that did not have a microfilter installed. Usually it's something the installer or customer overlooked, like the phone line to the cable tv box, satellite receiver, alarm system, garage phone, or secret phone the kids have tapped into the line so they can yack all night. Have the customer give you a tour of *ALL* their phones and check for proper DSL filter installation.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

If the problem turns out to not be in the house, a poor connection on the pair to your house can cause the same problem. Is there intermittent crackling on the line? I had this problem for 2 1/2 years until swbell finally put us on another pair. Chuck

Jeff Liebermann wrote in news: snipped-for-privacy@4ax.com:

Or one of the filters has failed due to lightning (or some such)...

Or better yet, split the line where it comes in and then you only need one filter. :)

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I found it useful to check unused phone outlets around the house as well. I had a forgotten one, which resided behind a group of house plants. Apparently, it got 'watered' a few times along with the foliage. Unterminated modular plug wires get 'terminated' over time by corrosion if they are allowed to get wet.

Over time, as the corrosion grows, the line at first gets noisy. Then it starts shorting out on application of ring voltage. Main symptom is a single, short ring when someone calls.

I can imagine the same sort of thing messing up a DSL line.....

jak

me hath wroth:

There's not much to fail inside. Inside a microfilter:

All passive parts.

The Siecor outdoor splitter is protected by zeners and two fuses on the input lines:

If it were hit by lightning, it would probably open the inductors, when would then result in no dialtone.

Incidentally, the connection between the line and the "DSL" port is straight through, with no components in the way (except perhaps the fuse).

However, I've seen far more improperly installed microfilters than defective filters. There's 3 ports on each filter, which offers 5 different ways to connect it, only one of which will work. Given the opportunity and the odds, the inexperienced user will usually get it wrong.

Much more common is installing the 3 port (line, DSL, phone) properly, but coming back later and plugging a phone into the unused DSL port. To solve that problem, SBC/AT&T now supplies one 3 port filter and 3ea

2 port filters, which can't have an extra phone plugged into the DSL port (because there is no DSL port).

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Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Sam Goldwasser hath wroth:

Yep. That's the right way to do it. Not only is there only one device to install wrong, but it has the benifit of isolating the DSL carrier from all the typically rotten wiring in the house. That's usually not important up to about 12,000ft, but becomes critical near the limits of commodity DSL at about 18,000ft. Such installs usually have problems getting enough line level and the telco will intentionally slow the connection down to reduce errors. I can sometimes squeeze a little more line level out of the system by using an outside splitter.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

There is one other factor which I didn't mention. There is an alarm system in the house. The CO has to hit the alarm system first. There is a double pole relay in the dialer with center connected to the CO. This relay normally is connected: CO to premises equipment. In the event of an alarm, the CO toggles over to the dialer, and "siezes" the line which in turn disconnects all premises equipment. If the incoming CO is split, someone could concievably short the DSL side during alarm dial out and circumvent the alarm. I've always installed alarm systems this way, first in line and never had a problem with DSL.. And alarm test signals go out fine. Only one pair seems to come into the house and is cut down in the basement. I don't see any filters there at all. And i never heard DSL when testing these lines. Lenny.

" snipped-for-privacy@yahoo.com" hath wroth:

Actually, I did. See:

It's in the list of possible oversights:

Yep. Alarms circuits are a special problem with special DSL filters with a specialized RJ-31x connector. They have to be first in line at the MPOE.

The idea is that if the alarm jack is unplugged, the alarm is triggered, but the phones continue to work. A commodity DSL splitter or microfilter will not work. It has to be something like this:

Incidentally, a few of the alarm panels I've seen recently include built in DSL filters and do not require any additional DSL filtering.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558