snafur
join:2004-11-05
| [Line Problem] random sync loss several times a day
It started a several weeks ago: DSL light flashing red for a minute or so, then sync restored for a while. In the beginning, it was once or twice a day, but now the sync drops several times a day. Checking the audible line quality, most of the time the line is quiet, sometimes the line is scratchy, and sometimes there is a 60 Hz hum. Nothing is consistent. Once, the dial tone was gone and we called it in, but got no feedback from ATT even though DT was restored.
For a few days after DT loss, DSL sync was stable. Then it started getting more unreliable as the days went by; now it drops out many times during the day and night. It happens without warning and can last for several minutes to an hour or so, and has just dropped as I'm typing this (the current link was up for about an hour.)
I'm in a semi rural area about 14k from the CO, but I suspect there's a RT of some sort in between. There is a history of poor POTS service in our area, and I suspect there are not enough good pairs serving the growing number of users in the area. I'd like to contact ATT Direct, but want to go in with all the info they'll need. I have downloaded a few modem logs and have a technician report to submit, but would like advice about the process and other info they'd require so I don't waste anyone's time.
Thanks for any help.
PS, as I wait for sync so I can post this, I'm on ATT Yahoo in MRY county but out of the Watsonville CO, using a Speedstream 5100b. |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA
| See the link at the top of the main forum page, where it says:
Please CLICK HERE for what to post to receive help with connectivity issues.
Please click that link and provide as much of the info as you can. That will help speed up the problem solving and hopefully save you the time and trouble of waiting in the Direct queue. |
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snafur
join:2004-11-05
| Thanks, tonydi. Here are the answers, in order.
The package is ATT Express. The modem is the Speedstream 5100b with 5 lights on the front. There is a Linksys WRT54GS plugged into the modem with a static ip address ...1.64. PPPoE is handled by the modem. The modem has been power cycled on occasion or just left on for the line to recover, which it always does eventually. (Indeed it has gone down a couple of times while I'm typing this.)
Normally, the first four lights (Power, Ethernet, DSL and Internet) are steady green, and the Activity light flashes when the packets flow. When the line goes down, the Power and E-net lights stay steady green, the DSL light flashes red for a while, then flashes green for a while and the Internet light goes out. Sometimes the DSL light alternates between flashing red for 5 seconds then green for 5 seconds, back and forth for several minutes (as it is now doing!) Usually, it re-syncs in about 30 seconds.
Listening to the line, it was quiet just now, but has had a slight hum, or some static on occasion (usually not at the same time.) I've checked that the other phones are plugged into the Phone port on the filters and none have been left unfiltered. And we lost Dial Tone only once that we know of. It's not effected by taking a phone off hook, either.
The line stats when it's Up are:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 16.0 -
Line Attenuation (dB) 53.0 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 2 1
Thanks for your help with this! I'll post this now while I have sync. haha. |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA
| Since it sounds like it drops sync often it will be easier to diagnose with different tests.
Those stats don't look bad enough to drop sync unless those CRC Error numbers change drastically or the SN Margin drops down below about 6 dB. So keep an eye on that stat page and refresh it often so you can monitor those numbers.
If the regular phone service is having any issues at all, that can definitely affect the DSL connection. And you're sure you have everything connecting to the DSL telephone number filtered except the modem? I'd suggest removing everything connected to the line except the modem and see if the sync problem remains.
You might want to also try hooking the modem directly to your NID and see if the sync remains steady there.
»AT&T Southeast Forum FAQ »How do I check modem stats, synch rates & speeds at NID - Residential Housin |
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snafur
join:2004-11-05
| OK. I've removed all other equipment on the line including the filters so only the modem is plugged in. The CRC errors have jumped to 553 - 1 so I'll power cycle the modem now, too. I'll come back later and let you know how stable things are like this. Thanks for your help. |
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snafur
join:2004-11-05
| Well, that didn't last long. I power cycled the modem and it has taken about 15 minutes to get sync back. Here is the Stats page from the brief moment it was Up during that time:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 32 384
SN Margin (dB) 2147483647.0 -
Line Attenuation (dB) 60.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 260 6
Now it's back to:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 13.5 -
Line Attenuation (dB) 53.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 12 2
I'm looking now for a 50 foot cable to run to the NID. Will that length be a problem? |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
| reply to snafur
I think you have a problem on AT&T's line beyond your NID. That wacky SN margin (SN Margin (dB) 2147483647.0) means your SN margin is a negative number and the bouncing attenuation (from 53.5 to 60.5) has been associated with a short and/or a cross on the pair.
By all means test at your NID. You might also try running the DMT tool on your techreadout results: »SBC DSL FAQ »How can I check for the maximum attainable sync speeds with a 5100b/4100 modem? . You might have to upgrade your firmware to get complete results: »SBC DSL FAQ »Where can I get the latest firmware update for my 5100B? .
If your NID tests results are bad, then you will have to start a trouble thread in AT&T Direct. |
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snafur
join:2004-11-05
| reply to snafur
Sorry if I'm posting too much info, but I did the test at the NID, and line stats aren't much different:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 14.0 -
Line Attenuation (dB) 52.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 2 2 |
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snafur
join:2004-11-05
| Thanks d_l. I read your response in another thread about the SN margin, too. In the meantime, I tested at the NID and all seemed OK. I could not do an extended test but the link has been stable since then. (I have connected my POTS equipment again, too, with all the filters.)
I have updated the modem software to 1.0.0.53, but when I try to use the DMT tool, all I get is a blank graph and limited data:
Downstream Maxrate (Estimated): 1536
Upstream Maxrate (Estimated): 384
Bit tones with notches/missing bits:
bit(s) 1:63 4.3125 - 276 KHz
bit(s) 65:255 280.3125 - 1104 KHz
Could this be because I'm on a Mac? I followed the instructions for saving the Tech Readout as html.
Thanks for your help. |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV | reply to snafur
It might be due to the browser you are using on the Mac. Whenever there is a weird DMT chart, it is usually due to the browser's handling of the html save. |
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snafur
join:2004-11-05 | I'm using Camino, the Mac oriented Firefox variant from Mozilla. I'll try Firefox instead. |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV | reply to snafur
Maybe try IE too? IE does require a little different save procedure, but it is described in the FAQ. |
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snafur
join:2004-11-05 | Unfortunately, IE hasn't been supported on the Mac for many years. The last version won't run on my iMac with Intel core. |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV | reply to snafur
Heh. No big loss.  |
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snafur
join:2004-11-05
| said by d_l  :Heh. No big loss. haha. I haven't missed it! I just pulled FF and got a better plot, I just can't figure out how to copy and paste it in here! go figger. The other data came along, though:
Downstream Maxrate (Estimated): 2584
Upstream Maxrate (Estimated): 844
Bit tones with notches/missing bits:
bit(s) 38 163.875 - 168.1875 KHz
bit(s) 40 172.5 - 176.8125 KHz
bit(s) 44 189.75 - 194.0625 KHz
bit(s) 47:48 202.6875 - 211.3125 KHz
bit(s) 51 219.9375 - 224.25 KHz
bit(s) 54:63 232.875 - 276 KHz
bit(s) 65:66 280.3125 - 288.9375 KHz
bit(s) 69:71 297.5625 - 310.5 KHz
bit(s) 73 314.8125 - 319.125 KHz
bit(s) 77 332.0625 - 336.375 KHz
bit(s) 80:81 345 - 353.625 KHz
bit(s) 84 362.25 - 366.5625 KHz
bit(s) 86:93 370.875 - 405.375 KHz
bit(s) 95 409.6875 - 414 KHz
bit(s) 98:99 422.625 - 431.25 KHz
bit(s) 102 439.875 - 444.1875 KHz
bit(s) 109:111 470.0625 - 483 KHz
bit(s) 113 487.3125 - 491.625 KHz
bit(s) 125 539.0625 - 543.375 KHz
bit(s) 134:255 577.875 - 1104 KHz
Does this help or is the graph more important? |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
edit:
May 7th, @11:42PM
| reply to snafur
The chart is pretty useful for the big picture. The individual frequency notches are more for zeroing in on the details.
How do you normally copy an image link with FF on a Mac? That is all you need to do on the chart and paste the link here.
Edit: Glancing through those notches, I think your chart is going to look pretty normal. Your line problem might be an all on/ all off intermittent condition with no obvious intermediate state. |
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snafur
join:2004-11-05
| Well, while trying to pull in the graph, the updated tech readout reported line 70, Gateway Ping Failure and line 80 Failure, too. It's now back to pass for both. I'm thinking this whole thing is a loose wire or a dirty connection causing things to drop or at least get marginal long enough for the switch to close my port loop. ??? |
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snafur
join:2004-11-05
| Well, today is a new day... sync dropped shortly after noon and didn't come back for 2 hours. Scratchy and noisy stuff on the line at the NID. Stats at this point:
Line State UP
Modulation ANSI
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 32 384
SN Margin (dB) 3.5 -
Line Attenuation (dB) 59.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 557 6
I guess I can call in the line now, but is it better to go through 611 or ATT Direct here? |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV | reply to snafur
611 would be better for POTS problems than AT&T Direct. When you call 611 don't even mention DSL. Let them clear the noises you hear and then see what your DSL is doing afterwards. |
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snafur
join:2004-11-05
edit:
May 8th, @08:29PM
| Thanks; I'll be back...
The truck rolls on Saturday... |
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