ADSL Noise Margin High!

Rik · Mar 18, 2009, 11:53:12

No, a profile reset is a one-off. You should now be on 7150 and, unless your sync speed drops, which it shouldn't, your speeds should be fine.

LesD · Mar 18, 2009, 20:44:35

Quote from: HoriZon on Mar 18, 2009, 11:44:00

I left my modem on for the next day in the master socket and through the night the sync came down while it was connected! lowest was 4700 kbps.

This is the bit I can't get my head round.

What brings your sync diown?

The only way I get my sync to change is by reconnecting my ADSL line to IDNet typically with a reboot or if something like a burst of noise makes the line drop and reconnect. This concept of the sync coming down of its own accord is alien to me. I believe something is forcing reconnections and each reconnection is at a different sync speed and what is causing these reconnections is what has to be discovered and fixed.

HoriZon · Mar 18, 2009, 21:57:16

Quote from: LesD on Mar 18, 2009, 20:44:35
This is the bit I can't get my head round. What brings your sync diown?

The only way I get my sync to change is by reconnecting my ADSL line to IDNet typically with a reboot or if something like a burst of noise makes the line drop and reconnect. This concept of the sync coming down of its own accord is alien to me. I believe something is forcing reconnections and each reconnection is at a different sync speed and what is causing these reconnections is what has to be discovered and fixed.

Thing is its not disconnecting the modem still reports the right up time and their are no logs in the routers logs that it has reconnected at all. It can change with-in the space of an hour or through the night but it does change its not fixed for me.

Latest stats after moving the modem upstairs:

Connection Speed 6976 kbps 832 kbps
Line Attenuation 27.0 db 12.5 db
Noise Margin 9.1 db 12.0 db

I also know my throughput is set to 4000 kbps atm but idnet say this will improve in the next few days it used to be 6500 kbps before all this started if not higher.

LesD · Mar 18, 2009, 22:10:17

Quote from: HoriZon on Mar 18, 2009, 21:57:16
Thing is its not disconnecting the modem still reports the right up time and their are no logs in the routers logs that it has reconnected at all. It can change with-in the space of an hour or through the night but it does change its not fixed for me.

It looks like my education is about to move on yet again when someone more knowledgeable that me explains this to me.

It is like you are in BT's 10 day trialling period all over again but I don't think this can be the case.

Lance · Mar 18, 2009, 22:42:27

The only way the sync will change is if the router has to reconnect to the exchange. This could be from a power cycle or noise burst for example. The sync will not just reduce without a reconnection.

Sebby · Mar 18, 2009, 22:46:57

I'm not sure why the router is not reporting the loss of sync events. If you're losing sync several times during the day, it suggests that there are bursts of noise occurring.

HoriZon · Mar 18, 2009, 22:47:49

Quote from: Lance on Mar 18, 2009, 22:42:27
The only way the sync will change is if the router has to reconnect to the exchange. This could be from a power cycle or noise burst for example. The sync will not just reduce without a reconnection.

Well this is what its doing its not reconnecting as it would leave that in the logs and it wouldn't have the same time up for the line as the modem it self.

My old modem did this as well.

Rik · Mar 19, 2009, 08:40:33

You're running a Netgear, so, get hold of a copy of Routerstats and leave that running for 24 hours.

http://www.vwlowen.co.uk/internet/files.htm

Some versions of their firmware have not reported sync loss.

HoriZon · Mar 19, 2009, 10:56:06

Quote from: Rik on Mar 19, 2009, 08:40:33
You're running a Netgear, so, get hold of a copy of Routerstats and leave that running for 24 hours.

http://www.vwlowen.co.uk/internet/files.htm

Some versions of their firmware have not reported sync loss.

Going to try this tonight good idea.

Also going to buy a new anti-surge ext lead where the modem is plugged into today!

On the newest firmware atm might go back one. Will try the stats and plug 1st though!

Rik · Mar 19, 2009, 12:57:09

Keep us posted.

HoriZon · Mar 19, 2009, 19:09:57

New plug didn't do the trick i then thought about the internal wiring.

As i was getting 8128 kbps all the time (well since idnet did some messing their end as i wasn't a few days ago) when it was in the 'test socket' but not the extension socket or the main socket when the face plate was on.

First i removed all the wires which were going to the extension and put the face plate back on full sync!

I then read up a bit about it, as i was a bit nervous in doing this.

Removed the 'bell wire' most sites say this is a good idea, i then noticed the white/blue (number 5) one on the master socket was in the wrong place it was where the blue/white (number 2) should be!! looked at the extension one and they were in the correct holes so it seems its been wrong for bloody years thing is BT installed them years ago when they still did internal wiring as the upstairs extension is the old ISDN socket. (What's odd though, it was working at 8128 kbps for years in this wrong state before a few weeks ago???)

I removed all the wiring from both face plates re-stripped the wiring down and put them in the right place!

Tried the connection and full sync!!!!!

Connection Speed 8128 kbps 832 kbps
Line Attenuation 27.0 db 12.5 db
Noise Margin 10.6 db 12.0 db

Code Select


BusyBox v1.00 (2008.03.20-02:06+0000) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

# adslctl info --stats
adslctl: ADSL driver and PHY status
Status: ShowtimeRetrain Reason: 0
Channel: FAST, Upstream rate = 832 Kbps, Downstream rate = 8128 Kbps
Link Power State: L0
Mode:                   G.DMT
Channel:                Fast
Trellis:                ON
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):       10.6            12.0
Attn(dB):       27.0            12.5
Pwr(dBm):       19.8            12.3
Max(Kbps):      8768            1128
Rate (Kbps):    8128            832
                        G.dmt framing
K:              255(0)          27
R:              0               0
S:              1               1
D:              1               1
                        ADSL2 framing
MSGc:           1               1
B:              255             27
M:              1               1
T:              1               1
R:              0               0
S:              1.0000          1.0000
L:              2048            224
D:              1               1
                        Counters
SF:             39352           39294
SFErr:          5               0
RS:             0               0
RSCorr:         0               0
RSUnCorr:       0               0

HEC:            3               0
OCD:            0               0
LCD:            0               0
Total Cells:    12824947                0
Data Cells:     8241            0
Drop Cells:     0
Bit Errors:     0               0

ES:             5               0
SES:            0               0
UAS:            20              0
AS:             669

INP:            0.00            0.00
PER:            1.75            1.75
delay:          0.25            0.25
OR:             32.00           32.00

Bitswap:        0               0

Total time = 11 min 44 sec
SF  = 39352
CRC = 5
LOS = 0
LOF = 0
ES  = 5
Latest 1 day time = 11 min 44 sec
SF  = 39352
CRC = 5
LOS = 0
LOF = 0
ES  = 5
Latest 15 minutes time = 11 min 44 sec
SF  = 39352
CRC = 5
LOS = 0
LOF = 0
ES  = 5
Previous 15 minutes time = 0 sec
SF  = 0
CRC = 0
LOS = 0
LOF = 0
ES  = 0
Previous 1 day time = 0 sec
SF  = 0
CRC = 0
LOS = 0
LOF = 0
ES  = 0
Showtime Drop Reason:   0
Last Retrain Reason:    0
#
#

My throughput is still low but this should improve over the next few days atm its:

QuoteYour DSL connection rate: 8128 kbps(DOWN-STREAM), 832 kbps(UP-STREAM)
IP profile for your line is - 4000 kbps
Actual IP throughput achieved during the test was - 3715 kbps

Going to keep and big eye on it for the next few hours, days, weeks!!

Hope my throughput goes up again i used to get a much higher one! if not its only an easy call to idnet to make!

I hope this is an ending to it all!

Rik · Mar 19, 2009, 19:13:34

Your profile will recover in the next few days. So often, wiring which was adequate for voice can prove inadequate for ADSL, even though it's worked for some time. Congratulations on your perseverance in tracking this down.

HoriZon · Mar 19, 2009, 19:20:21

I was sorta getting stressed out by all this its a annoying when its not working as it was

At least i have learnt a lesson check the wiring first all in all this has cost me time and stress and money (new modem, new extension lead)!!!!

Hope its fixed now! and i can stop moaning at idnet for something they cant control!

Rik · Mar 19, 2009, 19:22:30

At least you can smile at the end of it.

Sebby · Mar 20, 2009, 09:09:52

Great news.

HoriZon · Mar 20, 2009, 18:37:18

Well it stayed synced at 8128 for about 15 hours then it changed while it was on-line cos the noise went up :/

Now got it in the test socket where it will stay for a few days its still not on the full sync even here.

Connection Speed 7296 kbps 832 kbps
Line Attenuation 27.0 db 12.5 db
Noise Margin 14.4 db 12.0 db

Got that routerstats program running as well.

This is looking to me an out side problem tbh.

Will give it a few days like this but i cant use my main PC or 360 while it stays like this as they are in the other room and not wireless.

Rik · Mar 20, 2009, 18:44:08

Long ethernet cable? It does sound like an external fault, get IDNet to take a look at the line again on Monday.

HoriZon · Mar 20, 2009, 18:48:09

Yeah i might try and get a long one tomm, kinda a pain tbh but what more can i try when its still doing it with 2 modems in the test socket, with new every thing ! ?

Phones unplugged as well atm.

IDnet still say the line is fine and its not that, but it has to be.

Rik · Mar 20, 2009, 18:51:41

The risk is that, if they get BT out to you, and BT says the fault is your side of the test socket, then it's going to cost you £160+.