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[yousaf465]

http://soundcloud.com/drraptor/noise-while-dsl-is-up
This the sound heard in phone, when DSL is connected.

Also what equipment is used in a MSAN to separate Data from voice ?

[burakkucat]

Sorry. It appears that we all have missed your previous posting, with the picture. 

It is very difficult to say, as that is an unfamiliar connection block to us in the UK. Assuming that it is your responsibility, then it would not do any harm to remake the connections. 

Having listened to the audio recording, if that had been made when performing a quiet line test in the UK then I would definitely recommend a fault report should be opened. To me, it does sound like a high resistance or semi-conducting joint has developed somewhere along the line.

At a typical MSAN, there will be a low-pass filter for the telephony connection and a high-pass filter for the xDSL connection. The actual concept is nothing special.

It does seem to me as if you really need to ask for your CP to send a technician out, to make some tests from your end of the line.

[yousaf465]

Sorry. It appears that we all have missed your previous posting, with the picture. 

It is very difficult to say, as that is an unfamiliar connection block to us in the UK. Assuming that it is your responsibility, then it would not do any harm to remake the connections. 

Having listened to the audio recording, if that had been made when performing a quiet line test in the UK then I would definitely recommend a fault report should be opened. To me, it does sound like a high resistance or semi-conducting joint has developed somewhere along the line.

At a typical MSAN, there will be a low-pass filter for the telephony connection and a high-pass filter for the xDSL connection. The actual concept is nothing special.

It does seem to me as if you really need to ask for your CP to send a technician out, to make some tests from your end of the line.

I will remake the connection in morning. My setup is like, the yellow box is Extension double/master faceplate, while the black box is adsl spilitter.  Somewhat like setup 2 http://www.kitz.co.uk/adsl/splitter_install.htm

It wasn't a quite line test. this was heard while DSL was connected. It was recorded during from 11:39 onwards as shown in graph titled status.jpg.  Although I did a quite line test (kind of, I swtiched off the modem and recorded) in the afternoon.
http://soundcloud.com/drraptor/noise-while-modem-was-off


I did called the Operations branch of my telephone company/ISP , they said equipment for separating signals in ONU/MSAN( this ONU was installed recently) hasn't been installed as of yet. Could this be the reason ?

After my telephone line was shifted to new ONI I did faced Rectified Loop - Phone rings once then line cuts out. http://www.kitz.co.uk/adsl/connectionprobs.htm. It was solved, after which my current misery started.


I have attached graphs, for different times of the day. Status was recorded at 11:30am, sunset at 18:07 and night at 23:01.


During this time Upstream SNR remained around 6 stable. It doesn't vary at all almost. why is that so ?



 

[burakkucat]

Ah, I see. Thank you for explaining the picture.

Do you have a spare splitter (low-pass microfilter) available that you could try?

Listening to the other sound recording there is a hiss present, which is still indicative of a HR fault.

I find it somewhat difficult to believe that an ISP/CP would provide a service from improperly fitted equipment. I suspect that the person to whom you spoke was unsure of what to say . . . 

Would it be possible for you to show a Customer Service Representative of your telephony/Internet service provider copies of those graphs and let them hear your sound recordings? From everything that you have shown us, there is clearly a fault present on your line. I think you will just have to be persistent with them until such time as they agree to make physical checks of the line.

Remote diagnosis is very difficult to perform -- it is even more difficult when it is with a different service in another country. 

[yousaf465]

Ah, I see. Thank you for explaining the picture.

Do you have a spare splitter (low-pass microfilter) available that you could try?

Listening to the other sound recording there is a hiss present, which is still indicative of a HR fault.

I find it somewhat difficult to believe that an ISP/CP would provide a service from improperly fitted equipment. I suspect that the person to whom you spoke was unsure of what to say . . . 

Would it be possible for you to show a Customer Service Representative of your telephony/Internet service provider copies of those graphs and let them hear your sound recordings? From everything that you have shown us, there is clearly a fault present on your line. I think you will just have to be persistent with them until such time as they agree to make physical checks of the line.

Remote diagnosis is very difficult to perform -- it is even more difficult when it is with a different service in another country.

I do have spare splitter of same type. Will try it.

So hiss issue is confirmed. During night DSl  is quite stable, right now it's connected without any significant drop in SNR since more than 2 hours.  No major fluctuation except the minor REIN.


I wish I could send them these graphs.

[yousaf465]

Thanks everbody.

Today the DSL guy visited my location, remade the joint. Before this he also did something in the ONU and now my DSL is stable.

@burakkucat I did presented the graph and he was like  You have even plotted a graph.  I was like 

Thanks again. I have attached the current graph. I was testing the different modulations, ADSL2+, G.DMT etc which caused those disconnections.


ADSL2+ gives the lowest ping.

[burakkucat]

I'm pleased to read that you have now got a stable line. 

Looking at your latest graph, there is one thing that is significantly different to what is common in the UK -- your SNRM. Depending upon the stability of the line, we would normally see a target SNRM somewhere in the range of 3 to 15 dB.

[yousaf465]

I'm pleased to read that you have now got a stable line. 

Looking at your latest graph, there is one thing that is significantly different to what is common in the UK -- your SNRM. Depending upon the stability of the line, we would normally see a target SNRM somewhere in the range of 3 to 15 dB.

You are welcome. 


There might be a quite a few reason for that (randomly ordered)

• The use of a box which is significantly different from a face plate. It just almost directly connect the copper drop wire to the  RJ11 connector..
  
• Use of external wiring.
  
• The lowest stable margin is set to 6db. Normally it is not tweaked.
  
• The broadband is of Fixed type, in my case its a 4Mbps connection, syncing at 6Mbps with password set to 4Mbps.
  
• 30+ SNRM is common with ADSL2+ modulation only. with G.DMT it max out at 27-28.
  

ADSL Mode Setup    G.DMT    Annex Type Setup    ANNEX A
Current ADSL Mode    G.DMT    Current Annex State    ANNEX_A
ADSL Up Time    0:02:57    System Up Time    1:19:32
Downstream Rate    6016    Upstream Rate    1056
Latency Type    Interleaved    Line Coding    trellis on
SNR Margin US/DS    7.0 / 27.5    Line Attenuation US/DS    7.5 / 10.0
Power US/DS    12.0 / 19.5    Attainable Down Speed    12608
Link Up Times    0    Line State    Showtime
 

   
ADSL Mode Setup    Auto Sync-Up    Annex Type Setup    ANNEX A
Current ADSL Mode    ADSL2 PLUS    Current Annex State    ANNEX_A
ADSL Up Time    0:00:07    System Up Time    1:21:06
Downstream Rate    6023    Upstream Rate    1067
Latency Type    Interleaved    Line Coding    trellis on
SNR Margin US/DS    6.1 / 36.0    Line Attenuation US/DS    7.5 / 9.8
Power US/DS    11.3 / 15.9    Attainable Down Speed    27120
Link Up Times    0    Line State    Showtime


Currently   

ADSL Mode Setup    Auto Sync-Up    Annex Type Setup    ANNEX A
Current ADSL Mode    ADSL2 PLUS    Current Annex State    ANNEX_A
ADSL Up Time    16:29:22    System Up Time    16:29:53
Downstream Rate    6023    Upstream Rate    1055
Latency Type    Interleaved    Line Coding    trellis on
SNR Margin US/DS    6.9 / 36.3    Line Attenuation US/DS    7.6 / 9.8
Power US/DS    11.3 / 15.9    Attainable Down Speed    27284
Link Up Times    0    Line State    Showtime



I side question what is Power US/DS.


I do have a NTE5 socket laying around in my storeroom. Should I give it a try ? Just to  experiment.

[burakkucat]

It has all now become clear.   With such a short line, as shown by the attenuation ( US/DS    7.6 / 9.8 ), the target SNRM is elevated to such a value that your throughput speed does not exceed the package cap of 4 Mbps DS.

ADSL Mode Setup    Auto Sync-Up    Annex Type Setup    ANNEX A
Current ADSL Mode    ADSL2 PLUS    Current Annex State    ANNEX_A
ADSL Up Time    16:29:22    System Up Time    16:29:53
Downstream Rate    6023    Upstream Rate    1055
Latency Type    Interleaved    Line Coding    trellis on
SNR Margin US/DS    6.9 / 36.3    Line Attenuation US/DS    7.6 / 9.8
Power US/DS    11.3 / 15.9    Attainable Down Speed    27284
Link Up Times    0    Line State    Showtime

As long as it remains stable, I would be quite happy with the above.

The "Power US/DS" values are that of the transceiver outputs, measured in units of dBm, for your modem and the MSAN (ONU) respectively. Those levels are negotiated such that the "other end" (which depends upon the way your are considering the two-way link) can clearly receive the transmitted signal but not set so high as it then begins to affect other users' lines with crosstalk.

To be perfectly honest with you, I do not think fitting a BT NTE5/A to your line will make any difference. It might even violate the terms and conditions for the supply of your service. My advice is to err on the side of caution -- as everything seems to be working well, don't make changes for change's sake and leave well alone! 

[yousaf465]

SO if I lower the target SNRM, I might get more speed ?   

[burakkucat]

SO if I lower the target SNRM, I might get more speed ?   

If you are able to do so, then yes. 

Somehow, though, I suspect that your service provider will have blocked that route. 

[yousaf465]

SO if I lower the target SNRM, I might get more speed ?   

If you are able to do so, then yes. 

Somehow, though, I suspect that your service provider will have blocked that route. 

Thanks, but how can I set target SNRM with my modem ? Telnet probably ?

List of  ava. commands

Code: [Select]

ZXDSL 831CII> help
Valid commands are:
sys             exit            ether           wan
etherdbg        tcephydbg       ip              bridge
dot1q           pktqos          show            set
lan
ZXDSL 831CII>

further digging

Code: [Select]

ZXDSL 831CII> wan adsl
chandata        close           coding          defbitmap
linedata        open            opencmd         opmode
perfdata        reset           status          version
vendorid        utopia          nearituid       farituid
cellcnt         display         rateadap        dumpcondition
sampletime      noisegt         noisemargin     persisttime
timeinterval    defectcheck     txgain          targetnoise
txfilter        setrvid         txtones         snroffset
errorsecond     diag            watchdog        fwversion
uptime          dumprate        annex
ZXDSL 831CII
Valid commands are:
sys             exit            ether           wan
etherdbg        tcephydbg       ip              bridge
dot1q           pktqos          show            set
lan
ZXDSL 831CII> wan adsl targetnoise
usage: gain value should be snr margin(dB) * 512
current value:0

So what is relative capacity occupation

Code: [Select]

ZXDSL 831CII> wan adsl linedata near
relative capacity occupation: 100%
noise margin downstream: 36.4 db
output power upstream: 11.3 dbm
attenuation downstream: 9.8 db

Line data far

Code: [Select]

ZXDSL 831CII> wan adsl linedata far
relative capacity occupation: 100%
noise margin upstream: 6.6 db
output power downstream: 16.2 dbm
attenuation upstream: 7.4 db
carrier load: number of bits per symbol(tone)
tone   0- 31: 00 00 00 07 9a ab cc cd dd dd dd dd cc cc ba a8
tone  32- 63: 00 00 00 00 11 22 23 33 33 33 44 44 44 44 44 44
tone  64- 95: 34 44 44 43 43 43 34 44 44 44 44 44 44 43 33 33
tone  96-127: 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33
tone 128-159: 33 33 22 22 22 23 32 32 22 12 22 22 22 22 22 22
tone 160-191: 22 22 22 45 66 66 66 66 66 66 66 66 66 66 56 56
tone 192-223: 55 55 55 55 55 55 55 44 55 55 54 55 55 55 55 55
tone 224-255: 54 44 44 45 55 44 44 54 45 54 44 44 44 44 44 44
tone 256-287: 55 65 66 66 65 65 66 65 66 66 66 66 66 66 66 66
tone 288-319: 66 66 66 66 66 65 55 55 44 32 00 02 33 44 55 55
tone 320-351: 55 55 55 65 65 56 56 56 66 66 66 66 66 50 55 55
tone 352-383: 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55 55
tone 384-415: 55 55 55 44 44 44 45 54 44 44 44 44 44 44 44 44
tone 416-447: 44 44 44 44 44 44 44 44 44 44 44 33 33 33 33 32
tone 448-479: 21 10 01 22 22 33 33 33 33 33 33 33 32 32 32 22
tone 480-511: 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22 11

[burakkucat]

I'm sorry but I have absolutely no experience of that modem/router and so I am unable to assist you with its configurable settings. 

Perhaps someone else may have an idea? 

[rhohne]

The only experience I've had with a similar command set is with the Huawei HG520b in which I used the following commands

wan adsl close
wan dmt2 set snrmoffset xx xx
wan adsl opencmd adsl2plus
wan adsl open

where xx is derived from IntlSNRM below

Code: [Select]

Problem: How to change noise margin on P660HW-T1v2.

Solution: Here is an example to show the steps to change the noise margin.

Step1: Show the current noise margin;
 P-660HW-T> wan adsl linedata near
 noise margin downstream: 12 db
 output power upstream: 8 db
 attenuation downstream: 0 db
 tone   0- 31: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 tone  ..........

Step2: Delete CI command "wan dmt2 db tlb 10" in autoexec.net;
PS: Please reference other KB to edit the autoexec.net file.

Step3: Show current default offset value of noise margin;
 P-660HW-T> wan dmt2 show dmt
 ============= DMT SW setting =============
 %  txfltr_gain      = 0x8f9f4
 %  txfltr_type     = 0x1
 %  AGC reverb vref1, vref2, vref3 = 470  470  372
 %  rxfltr_type     = 0x2
 %  Loop length     = 0
 %  pilot tone      = 467
 %  watch tone      = 468
 %  TCM             = 1
 %  One Bit flag    = 1
 %  TargetNoiseMarg = 6144
 %  Sync flag       = 0
 %  echocancel flag = 0
 %  MOS             = 1280
 %  Budget MOS      = 0
 %  shapefilterflag = 1
 %  AGC clip counter= 255
 %  Rate4Sel= 0
 %  Rs= 1
 %  CG= 3738
 %  OlrCom= 1
 %  ModCG = 1
 %  ROS = 1536
 %  IntlSNRM= 1280 , FastSNRM= 1280
 %  force zero bit = 0
 %  ST SyncSym update = 0
 %  ST SyncSym Update Pattern = SEGUE

PS: This is in ADSL2/2+ mode. The default value is 1280.
If it's in ADSL mode, the CI command is "wan dmt show dmt".

Step4: Set new offset value of noise margin;
 P-660HW-T> wan dmt2 set snrmoffset 1792 1792
 offset = 1792/512    1792/512

PS:
If you want to increase 1 db, the new value should be 1280-(1*512)=768.
If you want to decrease 1 db, the new value should be 1280+(1*512)=1792.
If it's in ADSL mode, the command should be "wan dmt set xx xx".

Step5: Reset ADSL and check the result.
 P-660HW-T> wan adsl reset
 P-660HW-T> wan adsl linedata near
 noise margin downstream: 11 db
 output power upstream: 8 db
 attenuation downstream: 0 db
 tone   0- 31: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 tone  32- ...............

FYI attached is the bit allocation graph

[yousaf465]

The only experience I've had with a similar command set is with the Huawei HG520b in which I used the following commands

wan adsl close
wan dmt2 set snrmoffset xx xx
wan adsl opencmd adsl2plus
wan adsl open

where xx is derived from IntlSNRM below

Code: [Select]

Problem: How to change noise margin on P660HW-T1v2.

Solution: Here is an example to show the steps to change the noise margin.

Step1: Show the current noise margin;
 P-660HW-T> wan adsl linedata near
 noise margin downstream: 12 db
 output power upstream: 8 db
 attenuation downstream: 0 db
 tone   0- 31: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 tone  ..........

Step2: Delete CI command "wan dmt2 db tlb 10" in autoexec.net;
PS: Please reference other KB to edit the autoexec.net file.

Step3: Show current default offset value of noise margin;
 P-660HW-T> wan dmt2 show dmt
 ============= DMT SW setting =============
 %  txfltr_gain      = 0x8f9f4
 %  txfltr_type     = 0x1
 %  AGC reverb vref1, vref2, vref3 = 470  470  372
 %  rxfltr_type     = 0x2
 %  Loop length     = 0
 %  pilot tone      = 467
 %  watch tone      = 468
 %  TCM             = 1
 %  One Bit flag    = 1
 %  TargetNoiseMarg = 6144
 %  Sync flag       = 0
 %  echocancel flag = 0
 %  MOS             = 1280
 %  Budget MOS      = 0
 %  shapefilterflag = 1
 %  AGC clip counter= 255
 %  Rate4Sel= 0
 %  Rs= 1
 %  CG= 3738
 %  OlrCom= 1
 %  ModCG = 1
 %  ROS = 1536
 %  IntlSNRM= 1280 , FastSNRM= 1280
 %  force zero bit = 0
 %  ST SyncSym update = 0
 %  ST SyncSym Update Pattern = SEGUE

PS: This is in ADSL2/2+ mode. The default value is 1280.
If it's in ADSL mode, the CI command is "wan dmt show dmt".

Step4: Set new offset value of noise margin;
 P-660HW-T> wan dmt2 set snrmoffset 1792 1792
 offset = 1792/512    1792/512

PS:
If you want to increase 1 db, the new value should be 1280-(1*512)=768.
If you want to decrease 1 db, the new value should be 1280+(1*512)=1792.
If it's in ADSL mode, the command should be "wan dmt set xx xx".

Step5: Reset ADSL and check the result.
 P-660HW-T> wan adsl reset
 P-660HW-T> wan adsl linedata near
 noise margin downstream: 11 db
 output power upstream: 8 db
 attenuation downstream: 0 db
 tone   0- 31: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 tone  32- ...............

FYI attached is the bit allocation graph

These commands are working, but how can I delete

CI command "wan dmt2 db tlb 10" in autoexec.net;

in step 2 ?

I was able to change the offset value to 8960 from default 1280, but it is still snycing  at 36 db ( I didn't carried out step 2) 

Should I follow http://support.microsoft.com/kb/232558 for step 2 ?

current default offset value of noise margin

Code: [Select]

attenuation downstream: 9.8 db
ZXDSL 831CII> wan dmt2 show dmt

============= DMT SW setting =============
%  txfltr_gain      = 0xc0000
%  txfltr_type     = 0x1e
%  AGC reverb vref1, vref2, vref3, vref4 = 352  352  352  352
%  rxfltr_gain      = 0x14da
%  rxfltr_type     = 0x12
%  pilot tone      = 347
%  watch tone      = 348
%  TCM             = 1
%  MOS             = 8960
%  largeD flag     = 2
%  pilot retrain   = 1
%  TX IFFT Internal overflow = 0
%  TX filter dout overflow    = 0
%  tx_filter clip counter    = 0
%  AGC clip counter          = 0
%  rx_filter clip counter    = 0
%  RX FFT Internal overflow  = 0
%  Rs= 1
%  CG= 2298
%  New CG Flag= 1
%  CG offset= 1178
%  OlrCom= 1
%  ModCG = 1
%  ROS = 0
%  IntlSNRM= 8960 , FastSNRM= 8960
%  ST SyncSym update = 2  Pattern = REVERB
%  DEC cc32=0 , cc64=1
%  GHS AGC Gain=15
%  Init AGC Gain=7
%  medley_snr_threshold_for_ins_detect     = 2
%  medley_tone_ratio_for_ins_detect    = 20