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Standard User imaxtec
(newbie) Mon 10-Jan-11 03:26:45
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50mb un-stable bb speed (power/SNR help)

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Cable Modem Downstream
DS-1 DS-2 DS-3 DS-4
Frequency 435000000 443000000 451000000 0
Lock Status
(QAM Lock/FEC Sync/MPEG Lock) Y/Y/Y Y/Y/Y Y/Y/Y Y/Y/Y
Channel Id 236 237 238 0
Modulation 64QAM 64QAM 64QAM 256QAM
Symbol Rate
(Msym/sec) 6.952 6.952 6.952 6.952
Interleave Depth I=12 J=17 I=12 J=17 I=12 J=17 I=12 J=17
Power Level
(dBmV) -6.78 -7.77 -7.87 -23.18
(dB) 35.03 34.87 35.37 inf
Codewords 50912 51039 49220 0
Codewords 786 762 247 3107

Any advice about my power level and snr my broadband speed is not stable all the time pls advice me i am getting different speeds 24,30,and some times 45mb.

Thanks in advance

Standard User pete_thomson
(fountain of knowledge) Mon 10-Jan-11 09:01:23
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Re: 50mb un-stable bb speed (power/SNR help)

[re: imaxtec] [link to this post]
Might be better to have posted in the Virgin Media (Cable) forums.....

You need to contact VM. Your power level is generally too low and this could be causing a problem. Your power levels should be -3dBmV to +7dBmV. As yours are at -6.78, -7.77 & -7.87 so you are receiving under half of the minimum recommend level.

Also, how are you measuring the speeds? Speedtest websites vary a fair bit so it's an idea once the power levels are sorted to find one that work well and stick to it.
I use and the London server, this seems to be the most consistent and accurate one for me. If I select other servers I get speeds ranging from 8Mb to 40Mb.

Other speedtest sites I have found can show wildly different results too.

Virgin Media 50Mb/s
50.56Mb/s - 1.63Mb/s - 26ms @ 04/12/2009
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