Monday, 31 August 2009

Finding The Source of Interference


I've spent ages trying to find some useful and practical advice on ways to track down the source of broadband interference and it has been remarkably hard to find anything useful. Finally, I've managed to track something down which, although highly technical, does at least suggest some possible approaches. It also gives some good examples of the types of devices that can cause problems and how they do it.

The paper, entitled "Interference to Amateur Radio Reception," was produced by the Radio Society of Great Britain. Although it is intended for radio amateurs, it appears to apply equally to broadband reception.

In rural areas, electric fences may be a very specific source of broadband problems, particularly where they run close to, and parallel with, the telephone cables. If there are no long runs of parallel fencing, then well-maintained fences shouldn't normally cause too much of a problem. However, fences that are broken and shorted to earth, or ones which have green vegetation touching the wire or tape conductor, can put a large unwanted signal into the telephone lines, especially in wet weather. Buried telephone cables are particularly susceptible to this form of interference.

Typically, there is little information on this source of interference available in the UK from BT, who seem fixated with urban communities, but telecom providers and electric fence manufacturers in New Zealand do recognise this as a significant cause of problems in rural communities and have produced a very useful leaflet on the subject. This can be obtained from the Gallagher electric fence company.

Wednesday, 12 August 2009

Self-Help Measures to Try and Fix Speed and Connection Problems


UPDATE: Links to Jarviser's archived material updated in April 2014

There are several reasons why your broadband speeds can plummet, interference being one of the most likely causes. Look here for the types of thing that can cause such problems.

Phone Faults - Before doing lots of tests, you need to try and establish whether you really do have a broadband problem, or whether you have a phone problem that is affecting your broadband. You may have already noticed noises on your phone line, but to be sure, do the quiet line test.

Dial 170 70 and select option 2 when asked. Hold your hand over the phone mouthpiece, to stop it picking up noises, and listen. If you hear anything at all, you may have a problem. If you did hear anything out of the ordinary, try the test again, but this time disconnect the router and if you still hear noises, you probably have a phone problem - but it might be caused by your phone rather than you having a problem on your line. If you can, repeat the tests again with a different phone and if you still hear noises, you can be reasonably confident that you have a phone fault. You need to report this as such and in doing so, don't mention broadband! In this case, if the phone fault gets fixed, your broadband problems may go away.

Inside or Outside - OK, if it wasn't the phone causing problems, it might be something inside or outside the house. What we need to do is to determine which it is.

The simplest thing to try, if you have the correct sort of BT Master socket, is the Clean Socket Test. As is often the case when it comes to BT Broadband, the marvellous Jarviser has produced an easy step-by-step guide. It's important, as always when it comes to broadband, to follow Jarviser's instructions to the letter. More important in this case because if you get it wrong, it could cost you money! If the Clean Socket Test doesn't improve things, then chances are, the problem lies outside your home.

While we are on the subject of Jarviser, it's always worth spending a couple of hours browsing his website archive - there is a wealth of tried and tested information there - and I'll be referring to it a lot in this section.

If, for any reason, you can't do the Clean Socket Test, or even if you have done it and want to be certain that nothing in your home is causing problems, you can try switching every piece of electrical equipment in the house off, then turning them on one by one to see if that recreates the problem. Pay particular attention to devices connected to the internet like Sky boxes and extension phones. If it does, great, if it doesn't, try it all again with new microfilters on all the devices that need them.

Now work your way through the other tests on Jarviser's Broadband and Bellwire page. Perhaps the most important thing you can ever do to improve your broadband speed and connection stability, if you have extension sockets, is to remove the bellwire. This is so important, I'll say it again - remove the damned bellwire.

Why do this? Well, the now redundant bellwire (it used to be used to ring old-style phones) can act as a brilliant aerial, picking up all sorts of electrical and radio frequency interference from your home and dumping it straight on to your phone line.

If you really can't face pulling out a couple of wires, then, if you have the right sort of NTE5a Master socket, you could buy and fit an iPlate. It does a similar job to removing the bellwire, but isn't half as satisfying.

What else can you do? Well, problems with your telephone line and broadband connection might be caused by faults on your neighbours line, or their electrical equipment. If you are on speaking terms with them, you could ask if they are having similar problems, or if they have a new piece of electrical equipment. You might be surprised how helpful they can be, if you approach them in the right way. Here's one example where a little fault turned out to affect an entire village!

If you have a HomeHub 1.0, HomeHub 1.5, or many other commercial routers, particularly Netgear DG834 series routers, it is very worthwhile using RouterStats or RouterStats Lite, brilliant little freeware programs, to record your router stats continuously. The noise margin and sync speed traces will show any changes in either and you might be able to work out if a particular piece of equipment switching on or off might be causing your problems.

If you've worked your way through this checklist and still haven't found the fault, you are in a good position to call BT and not get charged for an engineer's visit as the problem seems to lie outside your home. Tackling the BT Help Line is not for the faint-hearted, so there is some advice here that might help. You also might also want to raise a question on the BT Beta Forum - and there's some more advice about that here.

The BT Forum can be a good way of getting action on a problem if you are having problems with the BT call centre in India; especially if the forum moderators take an interest. Alternatively, you can now raise your problem on Twitter!

Basic Information on Your Speed and Connection

The same symptoms of broadband problems - slow or falling speeds recur time and time again on the BT Beta Forum and other similar forums. Inevitably, the same problem requires a very similar answer, so here are the basic things you should do.

1. Collect the Basic information - The first thing to do is to collect you basic router stats. If you don't know how to find them, look here on the Kitz page for your particular router. They will look something like these.
Click on the picture to see an enlarged view. For the moment, the four most important sets of values are the System Up Time (Connection Time or similar), Connection Speed (the sync speed), Line Attenuation and Noise Margin (or SNR Margin). If you want to know what these represent, the Kitz website provides a useful guide here.

2. What Speed Could You Be Getting - this is a fairly difficult question, but you can get an idea by taking the Attenuation figure and putting it into the Kitz Maximum Speed Calculator. In my case, the Attenuation is shown 63.5 dB (its actually 68dB), but most routers will not record anything above this, so if your attenuation is 63.5 dB, what follows is very much a best estimate.

Now you can check to see what BT claim you should be getting. Kitz, thoughtfully, has another checker to help. Try this once with your post-code, once with your phone number and finally with both your post code and phone number. You may find a marked difference between them. My results are 1500kbps, 500kbps and 500kbps - a wide range of values. You can also get two measures of distance from the centre of your postcode, to the centre of the postcode where the exchange is situated - the direct 'as-the-crow-flies distance (3.44 km) and a calculated road distance (5.79km). In most cases, your actual line length will lie between the two values and be closer to the road distance. Unfortunately, some lines take circuitous routes and could be longer than those predicted. Thanks to BT, I know the exact line length between the exchange and the PCP (the green cabinet)is 3.361km and adding another 400m for the line length between the PCP and the house, gives me a line length of about 3.8km. Unusually, my line travels in virtually a straight line.

3. Your IP Profile - Now you need to run the BT Speedtester (NB You need Java TM installed on your computer for this to work). The important value here is the IP profile, in this case it's 1250 kbps. This fits with the sync speed of 1472kbps found in the first test and this one. With this IP profile, my throughput speed, the speed I can actually expect for downloading, is 1142 kbps. Compare that result, with this one, taken from the same line a few days earlier. Here, the sync speed is a little higher, but the IP profile is only 500kbps and the throughput is a pitiful 382kbps; a quarter of the throughput in the earlier results.

This last set of results show there is a problem with this connection - in this case it's a type of interference called Repetitive Electrical Impulse Noise (REIN). REIN causes the router to lose sync and the DLM at the exchange forces the IP profile down and the Noise Margin up(see first picture - Noise Margin = 12.9dB).

One last thing to do. If you are confident you have an accurate figure for your line length, you can ask the question - What attenuation and speed should I be getting? To work this out, go back to the Kitz Maximum Speed Calculator and vary the attenuation until the distance figure matches the line length you calculated earlier. For a line 3.8km long, a reasonable attenuation would be 53dB and the IP profile should be 3500kbps. Clearly, there is something badly wrong with this connection and in this case, it is because it links to the exchange with an old aluminium line, which suffers 50% more attenuation than a copper line of the same length. Remember though, these are only guideline figures and only as good as your calculation of the line length!

OK, now you have got all the router information you need to ask for help on the forums! Please take out any personal data, like IP address, home address and postcode before posting your stats on the internet!

Thursday, 6 August 2009

Rural Broadband and the Latest CLA Campaign


Rural broadband users often have greater problems when it comes to broadband, than do urban users. Often, this is because of the longer distances between the exchange and the End User, decaying infrastructure and decades of under-investment. The CLA (Country Land & Business Association) has been actively fighting for all rural areas to have effective and affordable broadband since 2002 when they firstly forced BT to introduce trigger levels and then lobbied, successfully, for a national rural broadband roll out in 2005. The CLA also produced an excellent contribution in response to the interim Digital Britain report - the final version of which can be found here.

I have written several times about the centrality of broadband access for the future health and development of the rural economy and for those who live in the countryside, and it is clear that all those working towards improving the situation, and narrowing the digital divide, need to work together as much as possible. The CLA are a significant voice in these efforts and, as you will note from the points above, have already made substantial progress.

On 4th August 2009, the CLA launched the 'Staying in Touch' petition as a voice against rural 'not-spots.' The CLA write:

High-speed internet access will be essential in years to come for all businesses – rural and urban – and those communities that do not have it will be at a severe economic and social disadvantage.

The CLA has said time and time again that Government investment is an essential prerequisite to rolling out broadband to all. This is a fair first attempt at trying to resolve the digital divide but more needs to be done if those in remoter parts of the country are to have a future in digital Britain.

If you think the Government should do more to provide effective and affordable broadband for all rural areas, please sign our petition.

It will be formally submitted to the Secretary of State for Business, Innovation & Skills Lord Mandelson by CLA President Henry Aubrey-Fletcher in October 2009.


If you are concerned about rural broadband access and the future of the rural economy, please sign the petition and make your voice heard!

Cross posted from: http://winterbournestoke-thedigitaldivide.blogspot.com/

Wednesday, 5 August 2009

Changes to the BT Support Forum



Kerry G, the Support Community Coordinator for the BT Forum is looking for ideas to improve the forum for users. If you have any ideas for the type of information you would like to see on the forum, the way the information is presented, or, I guess anything else about the forum at all, take a look at Kerry's thread here, and either add a post or, if you are the shy retiring type, you could always send an email with your ideas to: forum.moderation.team@bt.com
Having had some major problems with my own broadband service, I understand how others struggle to get help from BT.

There is a lot of good information out there, but it can be hard to find. So this blog is an attempt to pull some of it together, in one place.

It's a blog that really shouldn't be needed - if only BT and possibly other ISP's in the UK, provided useful customer support.