DSL disconnection problem

[[email protected]]

A customer of ours has complained that lately every time the phone
rings his DSL is disconnected from the internet. Has anyone seen this
problem before? Thanks, Lenny.

 

[Jeff Liebermann]

A customer of ours has complained that lately every time the phone
rings his DSL is disconnected from the internet. Has anyone seen this
problem before? Thanks, Lenny.

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.

 

[Chuck]

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.

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

 

[me]

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.

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

 

[Sam Goldwasser]

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.

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

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[jakdedert]

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

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

 

[Jeff Liebermann]

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

There's not much to fail inside. Inside a microfilter:
<http://802.11junk.com/jeffl/pics/dsl/slides/microfilter.html>
All passive parts.

The Siecor outdoor splitter is protected by zeners and two fuses on
the input lines:
<http://802.11junk.com/jeffl/pics/dsl/slides/splitter.html>

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).

 

[Jeff Liebermann]

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

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.

 

[[email protected]]

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 [email protected]
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060http://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.

 

[Jeff Liebermann]

There is one other factor which I didn't mention. There is an alarm
system in the house.

Actually, I did. See:

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.

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.
<http://www.hometech.com/learn/rj31x.html>
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:
<http://www.excelsus-tech.com/index.cfm?fuseaction=products.ProductDetail&id=1749711>

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