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leonardc9

join:2000-11-28
San Francisco, CA

DSL Loses Sync when Phone is Used

I went live with Cyberonic here in SF (94109) about 2 weeks ago. However, I've been having a major problem with my line and am hoping that people with more experience in dealing with telecos and ISPs might be able to help.

Whenever anybody picks up the telephone in the house, the sync is immediately dropped and dies. The DSL modem resyncs about 10 seconds to a minute later, but will go out intermittantly during the phone call. When the phone is placed back on hook, the sync will die again if it was able to retrain, and the resync process begins again.

I've reproduced this at the Network Interface with just the DSL modem and a single corded phone on a filter (tried different phones and different filters), so it definately isn't the inside wiring. In addition, Pacbell claims there's no MTU on the line. When the phone isn't used, the connection is solid and I love it.

I've spoken to both Pacbell and MCI/Cyberonic to hopefully resolve this problem. They claim that since they only deal with the voice side of things, since I have a dial tone and can call people, I'm okay in their book. Any problems with the DSL dropping (data side) are not their fault. Just got off a fairly frustrating call with an MCI tech (via Cyberonic) who claims that I'm also okay in their book since they only guarantee sync at the network interface and only under the condition that no telephones are ever used. Picking up the telephone (actually using phones(!) on my phone line) is not their problem since that is the voice side of the deal. The way they see it, the fact that DSL drops means that the voice side of things is messing with the DSL side.

So I'm stuck and frustrated. Both sides seem to acknowledge my problem and can see it. However, neither will fix it. Pacbell tests with the DSL modem disconnected from the line, while MCI tests with the DSL modem connected and the phones disconnected from the line. Both claim it's the other's fault. Yet the problem occurs due to an interaction between the two when both are connected.

Does anybody know who the responsible in this case and what my next steps might be?

Thanks,

Leonard


belushi
Premium,MVM
join:2000-11-08
Twinsburg, OH
I had the very same issue but it was caused by poor inside wiring in my previous apartment building. Replacing the cabling did the trick although you state that you were able to reproduce the issue at your demarc. Possibly inside your demarc is the problem. I would try and force your LEC to get a tech on-site and show them yourself what problem you are having. I know it sucks trying to get them out there.. You just have to complain till someone listens.

Reverend Ike
Premium
join:2001-08-24
Sacramento, CA
reply to leonardc9
Maybe something in one of these threads will help:

»DSL disconnect on phone pickup/hangup

»ADSL drop out

Robm15

join:2001-02-04
USA
reply to leonardc9
I had exactly the same problem you described. In addition if the phone rang, we lost sync. After weeks of complaining my service provider sent out a tech. He agreed it was a problem but could not figure out the problem. He went back to his shop and researched all technical service bulletins and found one that explained that if a certain type of switching relay were used at the CO it would react as described in your post. The technician promptly replaced the relay, he gave me the old one and I have it in my desk drawer, and I have had no problems since. I'm not sure if this will help you in your situation, because the real battle is convincing the service provider that the problem is on their end.


dslmadeasy
Got Ghost??

join:2003-02-01
Milky Way
reply to leonardc9
Please check out FAQ# 5120, sounds like you have Half-Ringer (or MTU) at the DEMARC that needs to be removed. Cyberonic
is responsible for that.

Also see these FAQ's and pictures:

»DSL FAQ » My DSL disconnects when I answer the phone

»Verizon Online DSL FAQ »What is a half ringer?
--
Oops, who said DSL supposed to be FUN and EASY to install?

leonardc9

join:2000-11-28
San Francisco, CA
said by dslmadeasy:
Please check out FAQ# 5120, sounds like you have Half-Ringer (or MTU) at the DEMARC that needs to be removed. Cyberonic
is responsible for that.

Also see these FAQ's and pictures:

»DSL FAQ » My DSL disconnects when I answer the phone

»Verizon Online DSL FAQ »What is a half ringer?

When I called 611 repair, they said they can remotely test the line and didn't find an MTU connected. How reliable are those tests?

Also, is it not true then that the only thing my ISP has to do is ensure sync to the demark? It sounds like the MTU is something Pacbell installs, but I have to convince Cyberonic to remove?

Thanks,

Leonard


dslmadeasy
Got Ghost??

join:2003-02-01
Milky Way
Some MTU won't show up on test, as pointed out in those FAQ's, MTU is only one of the possibilities although a bit higher probability than others as outlined in those FAQ's. CLEC is responsible for remove objects that cause unstability from DEMARC out (inside is your responsibility, you either do it yourself or pay someone to fix inside wiring unless it's covered under your subscription contract).

Actually it's pretty easy to remove MTU. Open your phone box and look for MTU, cut it out, rewire those TWO wires: green to green, red to red or what have you, and you are all set.

In addition, here is one 15-year boy's post installed a filter right at the DEMARC. Here is the POST without buying a dedicated SPLITTER as picture below:

and here is the link to order one:

»www.hometech.com/techwire/dsl.ht ··· dsl.html
--
Oops, who said DSL supposed to be FUN and EASY to install?


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
I had exact same problem that you described for over a year now. Since I use my cell phone as my primary number, the problem didn't bother me much until recently. To make long story short, my mother has gotten ill and I had her moved in with me for better health care arrangements. The DSL modem re-sync occurs more frequently as my mother phone needs increases. The problem is getting to the point that it is no longer a minor annoyance but a giant headache.

After reading a few related posts about this problem, I decided to call PacBell (SBC). However, I had no luck talking with SBC phone support persons. First, dial 611 for line and asked for line test and MTU check. Their responses were for my to contact the DSL support since they only handle the voice potion of phone line. So, I called the DSL technical support and found myself talking to a wall. I went through the song-and-dance with the micro filters on all phone jacks (both including and excluding the DSL modem) but all failed. The major downer was about the MTU. I asked the support person to have someone perform a MTU test. He didn't know what that was and called his second tier support for assistance. After several minutes, he told me that the MTU is software setting that he was not allow to check or modify. I told him that I asked for hardware line check for the Maintenance Test Unit (MTU) not the software TCP/IP packet size: Maximum Transfer Unit (MTU). He just kept argued with me over 10 minutes that it was a software setting. So, I asked him to transfer me to a second tier support person. The number that he gave me sent me back to the same automated phone tree that I first dialed. It was going in complete circle and endless loops. I finally gave up calling SBC for help in frustration.

After reading more posts with the same symptoms, some suggested the problem may cause my inside home wiring. Since I had nothing to lose, I purchased and installed a Seicor POTS Splitter and made a homerun line from NID to the DSL modem. However, the DSL modem re-sync problem still persists. I don't know what do next. Must I endure more phone sessions of frustration with SBC? All suggestions are welcome and appreciated.

Sorry about venting....


d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
kudos:7
reply to leonardc9
IdleDeamon, when you installed your homerun did you look for a half-ringer? See this: »Residential Install with PICTURES!!!!!

And this: »Is this a half ringer or someghing else in SNI

Maybe you need a half-ringerdectomy?


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
What does a half-ringer do? I'm nervous about cutting out stuffs that I don't understand. I don't recall see something like that when I installed the POTS Splitter. I'll open the DNI tonight and check for it. Thanks for the tip!

drainbamage

join:2000-10-30
Beverly Hills, CA
The MTU is no longer used by the voice side testers for remote testing and is no longer being deployed in CA to the very best of my knowledge. Also, on the West Coast you are looking for what looks to be a small circuit board that looks like it was dipped in a bucket of black paint ( still anything inline with the red and green wires can go ).


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
Click for full size
Click for full size
Is a MTU and half-ringer the same thing? :-[

I opened the DNI and took a copule of pictures. I found something that look like a MTU. Can someone verify my finding please.


ATTek
Got Sand?
Premium
join:2000-12-13
Glendora, CA
reply to drainbamage
said by drainbamage:
The MTU is no longer used by the voice side testers for remote testing and is no longer being deployed in CA to the very best of my knowledge. Also, on the West Coast you are looking for what looks to be a small circuit board that looks like it was dipped in a bucket of black paint ( still anything inline with the red and green wires can go ).
Nope, not installed anymore. They are still useful during MLT testing if they are present when working on non-DSL POTS problems. HOWEVER, I frequently encounter MTU's that MLT for whatever reason didn't see. So one MLT run on the line is not proof that an MTU is not there. Most of them look like the ones in IdleDeamon's picture:) They can also be an unpainted, beige circuit board or in some cases they're encased is grey plastic and say "Keptel" on them. *For the record:* ONLY SBC personnel should be fooling around with these and the CLEC has nothing to with it and should not be touching it. That being said, it's also true that removing this little bugger is something we should be doing before we certify the circuit for service. Idle, IM me with your DSL# so we can get someone out there to get rid of that thing for you:) And Leonard, are you able to post a pic of your NID opened up?
--
What does THIS button do.....

leonardc9

join:2000-11-28
San Francisco, CA
reply to IdleDeamon
Wow, IdleDeamon, that sounds almost exactly like my problem! Is your CLEC the same as mine (MCI/Worldcom)? If I find out how to resolve this, I'll keep you updated.

Leonard

leonardc9

join:2000-11-28
San Francisco, CA
reply to ATTek
Click for full size
Click for full size
Click for full size
Click for full size
said by ATTek:
And Leonard, are you able to post a pic of your NID opened up?

Of course! PacBellTek -- Thanks for your help in all this! While looking again at the NID, I realized that I could pop the little tray card for my apartment (Unit C). I noticed a black box similar to the one you mentioned might be an MTU. Pictures of the whole affair are below.


ATTek
Got Sand?
Premium
join:2000-12-13
Glendora, CA
There you go...that'll be your culprit.
--
What does THIS button do.....


d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
kudos:7
PacBellTek, what is the difference between an MTU and a half-ringer? I see the terms used interchangeably and I know they are very similar in physical appearance and effects on the DSL circuit, but I didn't know the differences. Thanks.


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
Leonard,

Looks like there are MTUs or half-ringers on our DNIs. PacBellTek had suggested to 'IM' Toaster2k for submitting a tickect for removal of the MTU by SBC personel. I had already 'IM' Toaster2k. I would suggest that you do the same. Hopefully, that will solve both of our problems.


kimodo

@dsl.pltn13.pacbell.n
reply to leonardc9
have you tried plugging directly into the cust side of the main terminal with a filter(two port/with phone) and your modem then calling your home number to confirm(loss of sync) and isolate your house

drainbamage

join:2000-10-30
Beverly Hills, CA
said by kimodo:
have you tried plugging directly into the cust side of the main terminal with a filter(two port/with phone) and your modem then calling your home number to confirm(loss of sync) and isolate your house
The MTU is inline before the testport and as long as it is there no further testing is valid.


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
With Toaster2k's help, a SBC tech came out and removed the MTU from my line. The re-sync problems are gone! Woohoo!

Thanks, Toaster2k!
--
Primary function: Avoid Work. If there work to do, then sleep. Awake after someone else did the work.


ATTek
Got Sand?
Premium
join:2000-12-13
Glendora, CA
Now if we could only figure out how to get Leonard's out of there:)
--
What does THIS button do.....


IdleDeamon
Zzzzzz Zzzzz
Premium
join:2003-06-03
San Gabriel, CA
reply to leonardc9
Ooops... Forgot to thank you too, PacBellTek and Barsoom!

You guys are cool! :C


d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
kudos:7
Well thanks for posting those pics, IdleDeamon, I learned a new place that MTU's can lurk.


sbcyahoouser

@covad.net
reply to IdleDeamon
Re: DSL Loses Sync when Phone is used.

I had the same problem too, and I also called them about it and they said nothing is wrong, just wait a few days and see what happens.
Kept calling and calling, finally I just called the SBC Phone side (not dsl side) and told me to send phone technician out (explaining the problem and sound really upset) , so finally the tech came out and it turned out they had this testing device on my line that was causing the DSL to drop connection when the phone rings or when is used. (was it a MTU??) Maybe since my building is probably about 30 - 50 years old. It looked like an 1.5" x 2" black plastic-looking rectangle with bits of wires on it (saw it pretty quickly, but it is square or rectangular, black with some wires). DSL and filters worked fine after he removed it. He was first helpful SBC tech I've ever encountered....REALLY! It took him literally 1.5 mins to talk to me in the apt, then he went out and came back 5 minutes later to tell me he figured out the problem. His name was French or Frenchy(?). Marin County Area, Northern CA.

leonardc9

join:2000-11-28
San Francisco, CA
A Pacbell tech just dropped by and removed the MTU. Probably the best customer service I've seen (dispatch was via automated voice prompt!) -- real friendly guy. Cyberonic has also been doing line tests and calling day after day, their customer service has gone up a few notches in my book too.

Everything seems to work great now!

Thanks to everyone for their help, especially PacbellTek!

Leonard


AlamedaCA

@dsl.pltn13.pacbell.n
reply to leonardc9
THANKS FOR THE HELP, FOLKS. IT SOLVED MY PROBLEM IN ALAMEDA, CA. I just went through a similarly frustrating experience with my new SBC Yahoo DSL installation. The customer service people know nothing about the MTU issue, and kept trying to focus me on the filters, which I had checked and rechecked. One second tier tech support guy pinged the line and determined there was a MTU, and said he would notify PacBell to remove it, but they never came. Then I had to start all over again with customer service, and they started in again with the filters. If they would only ask how old your house is, they could probably get to the cause much faster. Our house was built in 1955, and had 2 MTUs (circuit boards about 3/4 x 1.5 inch, potted in black, installed in series with the red and green wires)inside the Telco-protected side of the phone line entry box. Eager to get the job done, I was able to get my box open with some needle nose vise grips, although I am not recommending this - it is probably better to call PacBell at 611...Anyway, removing the MTU solved the DSL drop problem, which has been plaguing me for over a week. Thanks for the help, folks.


Gubus

@73.xx.37.Dial1.LosAn
reply to leonardc9
Is it a good idea to remove it befor a new install? Might everything be fine with the MTU left in?
Also, would removing it help with D/L speed?, or mostly helpful with sync probs?
Thx,
D