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Anonymous
(Unregistered)Wed 26-Feb-14 21:01:54
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Low SNR rate


[link to this post]
 
MY snr sits around 9 db but if I lower it to 6 or 3 db my sync rate actually gets worse not higher and I was wondering if there is a link between that and a 2 Mbps sync increase after a power cut, that increase soon disappeared though.
What do you lot think?
Administrator MrSaffron
(staff) Wed 26-Feb-14 22:32:27
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
Presume this is adsl2+

It may be lower noise margins mean too many errors or a combination of modem and dslam that don't behave perfectly

Andrew Ferguson, andrew@thinkbroadband.com
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Anonymous
(Unregistered)Thu 27-Feb-14 15:09:36
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Re: Low SNR rate


[re: MrSaffron] [link to this post]
 
Yes this is ADSL2+ sorry should have said that, the modem/router is a Billion 7800n and I'm on talk talk LLU.
I do get an extra Mbps if I use talktalk's router but compared to the billion 7800n its rubbish.
I will report back in a few hours with DMT tools error stats but unfortunately I have just restarted my router.


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Administrator MrSaffron
(staff) Thu 27-Feb-14 16:51:17
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
Probably best to include the full sets of stats too, rather than a verbal summary.

Cannot remember which routers that people like work best with TalkTalk. When I used them I just used the standard device as it was my second line and did nothing special.

Andrew Ferguson, andrew@thinkbroadband.com
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User ukhardy07
(fountain of knowledge) Thu 27-Feb-14 17:58:14
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
Is the SYNC getting slower ie the stats reported by the router or the actual speed, ie the speeds you get when you download something?

Two very different things.
Standard User Apprentice
(knowledge is power) Thu 27-Feb-14 17:59:53
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
Some views on routers and TT LLU.

plusnet user
Anonymous
(Unregistered)Sat 01-Mar-14 08:27:44
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Re: Low SNR rate


[re: ukhardy07] [link to this post]
 
The SYNC gets lower when the SNR goes below 6db.

this is the DMT tool stats:
Down Up
G.dmt framing
--stats
adslctl: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 916 Kbps, Downstream rate = 12716 Kbps
Path: 0, Upstream rate = 920 Kbps, Downstream rate = 10695 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 11.4 12.3
Attn(dB): 30.0 14.8
Pwr(dBm): 0.0 12.6

ADSL2 framing

MSGc: 51 12
B: 190 28
M: 1 1
T: 2 4
R: 0 0
S: 0.5699 1.0000
L: 2681 232
D: 1 1

Counters

SF: 9129951 782485
SFErr: 519 112
RS: 0 0
RSCorr: 0 0
RSUnCorr: 0 0

HEC: 361 62
OCD: 31 0
LCD: 0 0
Total Cells: 3741011205 321088177
Data Cells: 70538639 2682175
Drop Cells: 0
Bit Errors: 0 6132

ES: 426 126
SES: 0 0
UAS: 178 178
AS: 148303

INP: 0.00 0.00
PER: 16.24 18.00
delay: 0.14 0.25
OR: 28.07 8.00

Bitswap: 12504 145

Gap1 474kHz-479kHz (Tone110)
Gap2 548kHz-552kHz (Tone127)
Gap3 811kHz-815kHz (Tone188)
Gap4 824kHz-828kHz (Tone191)
Gap5 1048kHz-1052kHz (Tone243)
Gap6 1212kHz-1220kHz (Tone281-Tone282)
Gap7 1233kHz-1238kHz (Tone286)
Gap8 1255kHz-1264kHz (Tone291-Tone292)
Gap9 1376kHz-1380kHz (Tone319)
Gap10 1423kHz-1427kHz (Tone330)
Gap11 1440kHz-1445kHz (Tone334)
Gap12 1458kHz-1462kHz (Tone338)
Gap13 1466kHz-1471kHz (Tone340)
Gap14 1492kHz-1505kHz (Tone346-Tone348)
Gap15 1531kHz-1535kHz (Tone355)
Gap16 1548kHz-1552kHz (Tone359)
Gap17 1557kHz-1561kHz (Tone361)
Gap18 1794kHz-1798kHz (Tone416)
Gap19 1803kHz-1807kHz (Tone418)
Gap20 1811kHz-1816kHz (Tone420)
Gap21 1833kHz-1841kHz (Tone425-Tone426)
Gap22 1846kHz-1854kHz (Tone428-Tone429)
Gap23 1859kHz-1885kHz (Tone431-Tone436)
Gap24 1893kHz-1902kHz (Tone439-Tone440)
Gap25 1906kHz-1915kHz (Tone442-Tone443)
Gap26 1919kHz-1958kHz (Tone445-Tone453)
Gap27 1966kHz-1975kHz (Tone456-Tone457)
Gap28 1979kHz-1984kHz (Tone459)
Gap29 1988kHz-1992kHz (Tone461)
Gap30 1997kHz-2018kHz (Tone463-Tone467)
Gap31 2023kHz-2031kHz (Tone469-Tone470)

If you need anymore stats just ask.
Standard User XRaySpeX
(eat-sleep-adslguide) Sat 01-Mar-14 15:37:56
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
That's running slow.

What's those stats look like when you lower NM to 6dB?

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC
Anonymous
(Unregistered)Sat 01-Mar-14 17:58:13
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Re: Low SNR rate


[re: XRaySpeX] [link to this post]
 
G.dmt framing
--stats
adslctl: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 920 Kbps, Downstream rate = 12284 Kbps
Path: 0, Upstream rate = 920 Kbps, Downstream rate = 13899 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.0 11.9
Attn(dB): 30.0 14.7
Pwr(dBm): 21.0 12.6

thats with an SNR of 6db but if I lower it even more it usually gets a lower sync but this time its not going to do that for me, it was actually a few 100 kbps higher

G.dmt framing
--stats
adslctl: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 972 Kbps, Downstream rate = 10172 Kbps
Path: 0, Upstream rate = 971 Kbps, Downstream rate = 14179 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 2.4 12.9
Attn(dB): 29.5 14.7
Pwr(dBm): 14.0 12.8
Standard User XRaySpeX
(eat-sleep-adslguide) Sat 01-Mar-14 18:36:47
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Re: Low SNR rate


[re: Anonymous] [link to this post]
 
Even @ 6dB it's still running a bit below par. I'd expect > 15 Meg @ 6dB and gain 1-2 Meg from 3dB. But it's not drastically off..

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC
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