Acceptable T3/T4 amounts
 

Hi all
I have a long winded story about issues I'm having after getting a new SH2, rather than bore you all I just thought I'd just ask what would the guru's on here deem an acceptable amount of T3/T4's per day?
I'm having one or two.
Thanks Kc

Re: Acceptable T3/T4 amounts
 

one or two are no biggy dude, it is when you start getting 100 that there are problems but there is nothing you can do about them. If you are actually noticing any symptoms the best thing you can do is ring tech support, they'll send a tech out who will then escalate it to networks.

Re: Acceptable T3/T4 amounts
 

Have a read of this excellent primer here.

Re: Acceptable T3/T4 amounts
 

Thanks for replying
Did just that they checked power levels found them too low booked a repull (said I needed RG11 cable after trying to move me around the cab), networks came and broke a gas pipe outside my home stopped all works till gas got sorted, Then it gets better cable layers come lift up the blocks on my drive 3/4s of the way down my drive then leave when I call to find out when they will be finishing the job I'm told it's showing as completed.I start the whole process again sending a tech out who tells me they've re-pulled RG6 and my levels are acceptable now, so may not finish it just relay my blocks.
I'm waiting for the chuckle brothers to appear.
Kc
That's the condensed version.

Re: Acceptable T3/T4 amounts
 

Whatever the outcome they have to make good the drive.



It may be possible they had to lift a limited amount of your drive to find a collapsed duct in which case they would have only dug up to that, repaired it and completed the re-pull.

It is also possible that if the drive was laid after your service was supplied then that may have been the cause of you problem.

I'm still on the Chuckle Bros though as networks don't use any digging tools, basically they just replace and commission faulty cab equipment (rarely) and mostly can be found at the local hub replacing line cards, doing resegs drinking tea/coffee and eating biscuits.:D

Re: Acceptable T3/T4 amounts
 

My service was never under my drive, I had a great neighbour who let them dig his garden.
Although the blocks were lifted it's apparent no sand was disturbed.
The thing that gets me is all this was due to the tech saying I needed a re-pull now they're saying it's fine.

Re: Acceptable T3/T4 amounts
 

As you haven't had the re-pull how's your connection now? T3/T4's occur fequently on an intermittant basis on some connections but are not necessarily a cause for concern unless it impacts on your service.

If the lifting of the blocks on your dive has inconvenienced you in any way then get onto them for some form of compensation.

So far in this thread you only asked the question about T3/T4 errors but haven't' mentioned the impact (if any) it is having on you.

Re: Acceptable T3/T4 amounts
 

I get intermittent cut outs, pages fail to load they've checked utilisation and say it's fine.
I only have BB and phone at the mo but I'm 170 yards from the cab and the tech says if I choose to have Tivo as well I will probably suffer more.
Again I was relatively happy with the issues but looking on here and seeing my power levels were out of spec I phoned tech support who started this fiasco.
(They do say a little knowledge is a dangerous thing;))

Re: Acceptable T3/T4 amounts
 

So it's time for us to see your upstream, downstream and network logs. We can then tell you if adding Tivo will be a problem.

Re: Acceptable T3/T4 amounts
 

Good idea Seph, why the OP didn't do it in the first place is beyond me if he needs further info rather than just the answer to the question he asked.

Re: Acceptable T3/T4 amounts
 

Here you go
Attachment 24863
Attachment 24864
I must say though they've been as low as -14, but not for a few days.
Thanks for your input
Kc

Re: Acceptable T3/T4 amounts
 

Well if we could read them it would help. You've just uploaded the thumbnails. Try previewing your post next time then you'll be able to see what everyone else sees.

Re: Acceptable T3/T4 amounts
 

I can see that the downstream channels vary between -3.1 and -1.5. Is there an attenuator fitted to your SH2? If so, what value?

If not, then your situation for adding Tivo is currently marginal unless the engineer runs a separate cable from the external Ominbox to Tivo (so avoiding an additional splitter).

What I have noticed, though, is a high correctable error count. When it's that high (although errors are corrected in flight), you have to ask what's going on. The SNR/RxMER is in range although lowish on Ch 2, yet the errors are fairly evenly spread across all channels.

So let's look at your installation. If it comes from the neighbour's garden/drive, does that mean that the circuit has a splitter at his home that goes left to him and right to you? If so, that's the culprit. You're already 170 m from the cabinet and you're sharing what little power there is. A repull (changing from RG6 as was then the standard to RG11) with separate feeds from the cabinet to each of you would fix that problem - can still come through the neighbour's garden!.

As regards the T3/T4 events, your picture showed something that happened overnight-ish. We haven't got a feel for what's happening during the day and evening. The events shown in the network log are consistent with the circuit breaking down. Is the upstream power level stable to within 1 dBmv?

Re: Acceptable T3/T4 amounts
 

@ pip I thought you would be able to see them just fine as I could, I have always done it that way sorry if it's not clear.
@ Seph my service comes on it's own feed no splitters or attenuators to the house. I wanted to have it on my drive as my current neighbours are moving soon.
How would I get the info you need ?
Thanks again

Re: Acceptable T3/T4 amounts
 

Visible just fine here - Uploads are not thumbnails...

Re: Acceptable T3/T4 amounts
 

You'd look in your neighbour's garden where the VM cable comes in to an external wall box.

If it tees off to him and tees off to you, then you're sharing a cable from the cabinet and that would be bad news. Let us know and we can advise further.

Re: Acceptable T3/T4 amounts
 

Sorry i was referring to pip thinking i had not made my upload clearer.
My feed is not shared in any way.

Re: Acceptable T3/T4 amounts
 

Re my post.

My bad.

I was right clicking and selecting view image which showed a thumbnail.

Left clicking on it makes it viewable.

Re: Acceptable T3/T4 amounts
 

Thanks for that
The reason for this thread was to see what is an acceptable amount of errors per day to then push VM to finish what they started.
Going to call them tomorrow hopefully get the UK staff during day and see.
Thanks again for your input.
Kc

Re: Acceptable T3/T4 amounts
 

Of course your feed is shared ultimately via a tap at the street cab or in some cases via a pit in the street!

However that's just semantics but your description of how the specific "feed" to your external ominibox is what needs clarifying back ultimately to the street drop and the cab/pit itself.

Originally you appear to state that "repull" crew are attempting to lay RG11 on your drive? Subsequent post(s) appears to state your neighbour arranged for your service to be supplied via his "drive"?
You even later specify that because he's moving you want your service provided via your drive?

Since "WE" don't know the relative placements of your respective houses(property boundaries nor drives or whether they're shared in part) with respect to main street ducting then you'll need to both clarify and check for visible cable drops from the street run on the boundaries of both properties to establish whether the "feed" is shared at that point.

In a "conventional" street (for want of a better word) each property is adjacent to each other along the length of the street. However it happens that in some cases one (or even several) property may lie behind each other and have shared access to the public highway?

Either way you should start at the street looking for CATV pits on pavement and/or smaller round/square access points at boundary of nearest (or each property) nearest to the street. You may see visible small portion of ducting from an adacent cable T inspection cover penetrating a boundary fence/wall if you have one. If both properties have a frontage to the public highway in an adjacent "side by side - conventional" layout then you would expect an individual feed for each property. If their is only one then you may well have one "shared feed"?

In that latter scenario your own or your neighbours feed will typically be split from either of your individual external omnibox's mounted on the walls of your houses? Allowing for individual feeds to other rooms for seperate BB or TV STB's in additional rooms that may be laid horizontally or vertically then you should be able to establish this by the number of visible cables on each omnibox?(remember that a thinner telephone cable may exit the box which should be ignored in this context or may be part of a siamese type cable which also has the larger coax).

Whether you require RG11 (which has less distance loss and better propogation characteristics) rather than RG6 will then depend on relative distances from the Street Cab and whether a single street drop does in this case feed both properties?

Because VM's network inherited different original cable franchises that deployed slightly different CATV/RFI topologies originally then you can't apply a single rule to cover all the UK.
For example if I walk down my street in Hove then a street cab is located every 250-300m approx covering 48 domiciles split between both sides of the road.
Each frontage is approx 15m including the intervening shared drive between semi detached houses. Each property appears to be connected by RG6 and thus the worst case user to Street Cab length should be less than 150m worst case.
In another area/street with a terraced scenario then each frontage could even only be 5m and thus a 96tap street cab could be used instead of the 48tap cab in my scenario in order to reduce the number of street cabs(and thus potentially the number of amplifiers in the cascade chain back to O/E Fibre Node)?.

Good practise suggests you don't cascade (unpowered) splitters which is what Seph is trying to establish. So in an ideal scenario you will have say an individual feed from an individual tap in a streetbox and the only split will be either in your omnibox and/or after your internal wallbox. (viz 2 or less).
If say your street run/dop is more than say 150m then depending on the signal integrity(and any amp alignment) at your street cab then RG11 may be required instead of lower cost RG6?

One of the many reasons you can end up in this scenario is that from initial flood CATV cabling back to around mid 90's (and in some areas far earlier) then the HPPN (Homes Passed Per Node) calculation may have changed with new developments(larger property/site replaced with one or more dwellings) or (in case of some areas of Brighton & Hove, and Bath/Bristol etc) 3 story town houses converted to flats. Thus in 20years numerous public utility maintenance/upgrade work could potentially damage existing CATV ducts and reduce their cabling capacity, and street cabs become congested with multiple splitters off limited original tap board capacity and so on.

VM is slowly addressing this Cab congestion as well as re-segmenting in some cases to blow fibre deeper into the network closer to the user to reduce the HPPN and amp cascade numbers closer to N+1 (and eventually at some far far future date actually potentially facilitate even FTTH/P).

Of course unless you're a sad individual like Seph or myself all this is hidden from a laymans perspective unless you are specifically looking for the clues? ;)

Re: Acceptable T3/T4 amounts
 

Sorry for the delay replying horseman took me a while to digest your post. :D
Barring the semantics, and to clarify my feed is a single RG6 from the cab to my home up to the grey box which would normally split between the digibox and the SH2 but as I don't have the tv connected it goes straight to my SH.
Regarding the neighbours, my original feed was laid over 10 years ago when my then neighbour allowed VM to sink it in his garden, he has since died so my current neighbours who are due to move soon are not as keen and neither am I, so I've asked for it to be laid under my drive.
To repeat the original reason for my thread was to see if there was an acceptable amount of errors in a "normal" service.
Kc

Update:

VM have booked another re-pull of RG11 for the 13-09-13 so hopefully all will be sorted.
Thanks to all who've advised on this it is appreciated.
Kc

Re: Acceptable T3/T4 amounts
 

Good luck! Hopefully the repull will go well.

Re: Acceptable T3/T4 amounts
 

In short:

The odd T3 is not a major concern.

The pre errors you have are huge and should set alarm bells ringing. Your modem seems to be coping with them quite well but something is seriously wrong somewhere.

If a repull for RG11 can be done then do it but there are many things that can cause such errors such as faulty joints, connectors, modems, isolators and tap ports in cabs.
You need to get a tech that will spend time replacing everything that can be replaced and even test for these errors directly off the cab as it could be causing issues for your whole street.

Re: Acceptable T3/T4 amounts
 

Jonnymeg
Thank you for your input, although I have learned a great deal from this forum which has enabled me to deal more effectively with VM I am not able to read the logs and up/down stream info like the experts on here can.
I knew something was wrong but didn't know what to look for and only posted after VM said my stats were fine.
I should have posted my stats in my first post so apologies for that.
Hopefully after the repull things will improve.
Thanks again
Kc