Menu
Reply
  • 9
  • 0
  • 0
oldmortality
Tuning in
259 Views
Message 1 of 5
Flag for a moderator

5mb on 200mb service

My download speed is very slow - this is a new install last weekend in TW9.

Are my downstream levels within spec? From what I can tell the SNR is on the low side, at 27-29 dB. Power levels -5 to -7.5dBmv, which I can't seem to get to display properly!

 

Downstream bonded channels Channel Frequency(Hz) Power
(dBmV) SNR
(dB) Modulation Channel ID

1299000000-5.529256 qam9
2323000000-4.730.1256 qam12
3315000000-5.229.6256 qam11
4307000000-5.529.4256 qam10
5291000000-5.528.9256 qam8
6283000000-5.728.6256 qam7
7275000000-7.527.8256 qam6
8267000000-6.927.8256 qam5
9259000000-6.227.8256 qam4
10251000000-6.227.8256 qam3
11243000000-6.527.3256 qam2
12235000000-6.427.6256 qam1

Advice appreciated!

Matt

0 Kudos
Reply
  • 454
  • 21
  • 101
Andy1975
Fibre optic
250 Views
Message 2 of 5
Flag for a moderator

Re: 5mb on 200mb service

Unfortuantly Virgin media is superglued together and the number of connections and demand to a CMT changes its min/max power limits on what is too high and is too low and also what Hub/modem you have.

As a general "what you would like to see as your power levels" it would be.

Downstream between -3dBmv to +7dBmv

Upstream between 35dBmv to 55dBmv

However It is quite possible to have power levels outside of these limits and have no issues... You having -6dBmv downstream is "going by the rule book" too low... This would affect SNR also.

If you have a silver block on the back of your superhub where the coax cable screws in that is called an "attenuator" then this can be removed easily to increase power levels, there is a value writen on them saying how much it is reducing the power level by in dBmv (E.G. 6dBmv)... If you do not have one and your power levels are too low (wait for admin to say so) for your CMT then and engineer will be called out to alter/change tap points in the cab on the street.

 

  • 9
  • 0
  • 0
oldmortality
Tuning in
214 Views
Message 3 of 5
Flag for a moderator

Re: 5mb on 200mb service

Thanks Andy,

Really helpful. Unfortunately no silver block to remove and I have the Hub 3.0.

Just trying to work out whether this issue is the connection itself or contention. From other posts in the area (Richmond) it seems to be a particularly bad problem in the surrounding area - is there a way to check this?

Pretty disappointing for a 200mb service, but tonight I'm getting about 10mb and streaming video isn't even working properly!

Matt

 

0 Kudos
Reply
  • 9
  • 0
  • 0
oldmortality
Tuning in
175 Views
Message 4 of 5
Flag for a moderator

Re: 5mb on 200mb service

From other posts it appears that my area, area 03 near Richmond in London, is massively oversubscribed.

Unfortunately this really is making the connection nearly unusable at peak times; I seem to still have a few days before the cooling off period expires.

If there isn't a marked increase in performance within this time then I will have to go elsewhere.

Does anyone know how to find out if VM have upgrade works in the pipeline?

Matt

0 Kudos
Reply
  • 10.82K
  • 308
  • 631
Forum Team
Forum Team
123 Views
Message 5 of 5
Flag for a moderator

Re: 5mb on 200mb service

Hi Matt, 

Thanks for taking the time to post on the community. 

Sorry to read that you are having issues with your broadband connection. 

I've managed to locate your account and there is an SNR (signal to noise ratio) fault in your area which is causing intermittent connection. The reference number is F004861737 and with a review date of 14th November. There is also maintenance being completed in your area today.  

Once the SNR fault has been closed down I will take another look at your connection and if there are any issues with the line, I can arrange an engineer appointment.

With the power levels, the downstream range is between -6 dBmV and +10 dBmV and with the upstream anything under 51 dBmV is acceptable. Hope that helps.

Speak soon

Sam


New around here? To find out more about the Community check out our Getting Started guide


0 Kudos
Reply