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Standard User Phil215
(newbie) Tue 29-Jan-13 02:01:09
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Sagem F@st 800 diagnostics


[link to this post]
 
Hi folks,
Recently, following a very frustrating experience trying to get some action from BT regarding my failing broadband connection I went in search of answers online.

(A little background info.- I was experiencing frequent line drops. My ISP, Demon, said my line failed their broadband test on 24th Dec. It took until 8th Jan. before BT decided to close the fault call, yet they said nothing about their findings.)

Online research soon turned up the interesting document "UKphonecatwiring.htm" and I followed the advice it contained about installing a custom NTE5 plus ADSL face-plate as a plug-in addition to an LJU style master socket. This proved very successful. However, I wanted to gather line stats using a Sagem F@st 800 modem exactly as in the document mentioned.

I bought the Sagem and downloaded and installed the driver, but when I examined the software I found it didn't have the "TEST" or "Graph" tabs in the Administrative window.
Can anyone please tell me which version of Sagem F@st 800 software has these features, and where to find it?
Standard User David_W
(experienced) Tue 29-Jan-13 02:25:39
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Re: Sagem F@st 800 diagnostics


[re: Phil215] [link to this post]
 
The document to which you were referring can be found here.


Whilst an interesting document, it hasn't been updated for a while. The wiring advice is still reasonable - get rid of unfiltered ring wires, ideally by using a centralised filter as close as possible to the master socket.

Rather than adding your own NTE5, these days you can usually persuade your telephone provider to get BT Openreach to replace your existing master socket with an NTE5 (which may be referred to as a Linebox) free of charge if you don't already have one. The latest BT Openreach logoed NTE5s have a filter that largely eliminates the extension ring wire problem, though it's still preferable to use a faceplate filter or, if your phones are happy without it, disconnect the ring wire at the master socket.

The latest centralised filtering solution from BT is the VDSL interstitial filter, which is used for fibre to the cabinet broadband (i.e. VDSL2) installations, but works equally well for ADSL products.


The Sagem modem mentioned is an old USB ADSL modem which does not support ADSL2 and ADSL2+ (so it cannot connect statistics for these faster modes if your line supports them). It's quite possible the latest drivers omit the diagnostic application, especially if you are using a later operating system than Windows XP. However, section 3.3.2 of the manual may help.

What router do you normally use? Most ADSL routers can be persuaded to give some form of statistics - at least the key parameters of speed, noise margin and attenuation in both directions. This site may help you.

Standard User Phil215
(newbie) Tue 29-Jan-13 14:27:21
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Re: Sagem F@st 800 diagnostics


[re: David_W] [link to this post]
 
Thanks for your prompt reply David_w. Now I see why the Sagem lacks the diagnostics I expected.
My trusty Speedtouch 546v6 has been operating well for several years but last week I
decided to reconfigure the network using wireless. I bought the 585v6 and located it
next to the master socket. The idea being to completely eliminate the extension wiring.

Initial testing using RouterStats Lite produced an interesting graph which appears to
show the frequent loss of DSL that I was originally complaining to BT about.
The first test of only 50 minutes duration shows no less than 13 drops.
Can you confirm that this is abnormal line behaviour before I launch a further salvo at BT?


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Standard User systemx
(experienced) Tue 29-Jan-13 14:45:27
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Re: Sagem F@st 800 diagnostics


[re: David_W] [link to this post]
 
On the face of it there is nothing wrong with fitting a NTE-5 as proposed in the article. However this does lead to a double mastered line and while this may have little effect on BB performance, it may lead to line test problems.

The problem is easily solved or prevented by removing the components (capacitor, out of service resistor and over volt protection) from the NTE-5.
Standard User David_W
(experienced) Tue 29-Jan-13 15:12:54
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Re: Sagem F@st 800 diagnostics


[re: systemx] [link to this post]
 
In reply to a post by systemx:
On the face of it there is nothing wrong with fitting a NTE-5 as proposed in the article. However this does lead to a double mastered line and while this may have little effect on BB performance, it may lead to line test problems.

The problem is easily solved or prevented by removing the components (capacitor, out of service resistor and over volt protection) from the NTE-5.
I join you in recommending removal of master components from a slave NTE5 (one fitted to a line with an existing master socket). I would certainly remover the resistor and spark gap. If you've got a DSL filter fitted, the capacitor is redundant, too.

All you need to do is snip the components off the slave NTE5's circuit board.

Standard User David_W
(experienced) Tue 29-Jan-13 15:34:59
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Re: Sagem F@st 800 diagnostics


[re: Phil215] [link to this post]
 
In reply to a post by Phil215:
Initial testing using RouterStats Lite produced an interesting graph which appears to
show the frequent loss of DSL that I was originally complaining to BT about.
The first test of only 50 minutes duration shows no less than 13 drops.
Can you confirm that this is abnormal line behaviour before I launch a further salvo at BT?
Before contacting Demon, it may be worth posting the statistics and graphs on some web space, then posting the link here for people to review first, before contacting Demon.

If you are losing sync 13 times in an hour, that is a fault - you should be able to hold sync for several weeks on a reasonable line. Ideally you'd be testing in a BT NTE5 test socket to eliminate your wiring completely, but you don't have that option. If a BT engineer comes to your house as part of fault finding, ask him or her to replace your existing master socket with an NTE5 - they will probably do that anyway, but it never hurts to ask. You can then move your filter to the BT NTE5 - though keep the faceplate as you will need it if you fit the VDSL interstitial filter in the future.

If the ADSL fault is resolved without an opportunity to have a BT NTE5 fitted, contact your phone provider to ask about having one fitted. It will probably be free of charge, and will give you a test socket for future troubleshooting.


Demon aren't, in my opinion, the ISP they once were after all the takeovers. I was with them from 1996 until the ScottishTelecom days, when ntl (as it was then - it later became part of Virgin Media) launched cable modem service in my area and I could get a faster connection without the horrific ISDN call costs I was incurring. Eventually, the BT exchange was upgraded to support ADSL and the quality of the ntl cable modem service had deteriorated, so we moved from ntl to Zen ADSL in 2004. I'm still with Zen, though our cabinet was enabled for FTTC last month and we upgraded earlier this month.

At one point, Demon's technical support was excellent. I'm not sure how good they are now. If you don't get the backup you want, consider moving - there are excellent ISPs out there with UK based support centres at various price points. The more expensive ISPs (such as Zen, AAISP and IDnet) tend to be more persistent over faults

When on Zen ADSL, I had problems with a sizeable drop in sync speed and disconnections that was down to water in a joint. Twice, BT did a pair swap and closed the fault, but it was not resolved. Each time, I contacted Zen who re-opened the fault (it did not affect voice, so I had to go via Zen rather than my phone provider, BT Retail). The third engineer checked all the joints and found the joint in the underground DP where our drop cable connects to the D-side was waterlogged. The engineer disassembled and dried out that joint, replaced the crimps on our line, and everything was back to normal.


Ultimately, every ISP are at the mercy of BT Openreach, but if Demon refuse to persist with your problem, consider moving ISP. Even if you don't move ISP now, this is a good reminder to eliminate your dependence on ISP provided e-mail addresses and web space, so that you can move freely in the future.

Standard User Phil215
(newbie) Wed 30-Jan-13 17:01:02
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Re: Sagem F@st 800 diagnostics


[re: David_W] [link to this post]
 
Yes, I was well aware of the impending dual master socket configuration whilst I was wiring up my shiny new NTE5 from Clarity. I went ahead with it by reasoning that it was unlikely to be detrimental to my line if it was still advocated in "UKphonecatwiring.htm".
Surely, if it was wrong that document would have either been updated or taken down.

Anyway, I send an e-mail to BT last night reminding them that their work on my line was not
finished, regardless of who closed the fault call on 8th Jan.
This morning I ran RouterStats again for 1hr 50 mins and the connection graph was an
unbroken horizontal line, just as it should be - amazing! It seems very unlikely that this could be a coincidence, unless by fixing another subscriber's fault they accidentally made a positive impact on my line.

On 17th Jan. Demon said they reckon the length of my line is 4.387 km. Kitz estimates it to be 3.7 km. (When I get time I'll verify which it more accurate using a local map.)
So, the line is long and consequently heavily attenuated, but the ST585v6 does a good job of training to the local DSLAM. Here are some figures from the event log, taken at midday:
------------------------------------------------------------------
xDSL linestate up. Downstream: 4355 kbps, Upstream: 951 kbps.
Output power, down: 15.5 dBm, up: 12.0 dBm.
Line attenuation, down: 57.5 dB, up: 36.0 dB.
SNR margin, down: 10.5 dB, up: 6.0 dB.
------------------------------------------------------------------
I shall continue to monitor the line occasionally, particularly during wet weather, when it used to be especially bad. Perhaps this is symptomatic of cable waterlogging.
Thanks to all who have commented in this thread, it's much appreciated.
If you think there's any point in trying to tweak the ST585v6 to get better performance I would like to hear your suggestions.
Now I'll probably get a warning from the forum administrator for encouraging the thread to drift off topic!
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