On several past occasions, dating back to 2008, Wireless Waffle has reported on how several users of the short wave spectrum including radio amateurs, broadcasters, air traffic controllers and NATO, have raised concerns about interference caused by power-line telecommunications (PLT) devices (such as the Comtrend unit pictured on the right). PLT devices allow the use of home electrical wiring to carry computer data by injecting radio signals over the wires. As electrical wiring is designed to carry signals with a frequency of 50 Hz and not 5 MHz, the injected radio signals have a tendency to leak out everywhere and cause radio interference over a wide area.

Groups such as UKQRM and Ban PLT have long campaigned that PLT devices (also known as Power Line Adapters) should be taken off the market as they do not comply with the relevant emissions standards.

Over all of this period, the UK spectrum regulator Ofcom, has staunchly refused to accept that these devices contravene any regulations, though they have taken action in a number of cases where the interference they cause has exceeded even their expectations. Over the same timeframe, a number of other devices have also been found to cause high levels of radio interference, particularly cheap electrical devices, often imported on the grey market from China. These include things such as laptop power supplies, LED lighting and solar panel electrical controllers. Yet Ofcom continued to refuse to accept that anything needed doing.

It is therefore somewhat of a bolt from the blue that on January 15th, Ofcom released a consultation document, entitled 'Notice of proposals to make The Wireless Telegraphy (Control of Interference from Apparatus) Regulations 2015' in which it wishes to implement new controls over these devices by making it a criminal offence to operate them if they are causing interference to wireless telegraphy (e.g. radio services). Part of this seems to be driven by the fact that Ofcom were unable to deal with many interference complaints under existing regulations and that this could be regarded as a potential safety-of-life threat where the interference was caused to, for example, aeronautical services.

According to the consultation paper, there were 114 cases of interference reported in 2014, 'where undue interference was caused ... and capable of resolution'. Of those 114 cases, only 3 could be cured quickly using existing legislation and in the other cases it required voluntary action by the user of the equipment to bring about a solution. Under the proposed changes, all of these cases could be dealt with by law, meaning that instead of volunteering to fix the problem, users could be prosecuted if they didn't.

The big question has to be whether such a change would make any difference. Would those selling the devices stop doing so? Presumably not, as there is no law against selling them, just using them. Would they warn buyers of the new law? Not if it damaged sales. And what will happen if Ofcom threaten prosecution to someone who believes they have been using equipment quite legally, having purchased it legitimately, and having seen the various markings on the box that said it complied with the necessary standards? Will Ofcom then look silly for allowing such devices to have been sold in the first place? Sadly, the UK legislation on such things is still somewhat muddy. It is possible to sell, for example, FM transmitters, mobile signal boosters and even GPS jammers. It is just not legal to plug them in and use them.

Ban PLT are recommending that as many people as possible respond to the consultation, encouraging the changes to be implemented. No doubt organisations which manufacture or sell the devices will be arguing against the changes and so it is important that those who use the radio spectrum, especially the short wave spectrum, respond to show the strength of feeling.

There is an old saying in England, 'closing the barn door after the horse has bolted'. Effectively it means trying to solve a problem, after it has happened. The new powers proposed by Ofcom may have some effect in allowing Ofcom to convince users to turn off whichever device it is that is causing the problem, but it is by no means certain that the threat of 'turn it off or we will sue' is going to win anyone any friends, Ofcom, suppliers, BT and radio listeners alike.

It's easy to forget that the radio spectrum has been in use for over 100 years, but that then (as now!) communications has not always been wireless.

During World War I, teams of 'signals' engineers risked life and limb to lay down wires to allow communication between the front line and the headquarters.

"Signals From The Great War" takes the reader back to these times through a series of mémoires written by Archibald Gordon MacGregor RE MC combined to tell the story of a young signals officer's experiences on the front line in Belgium and France from 1917 - 1919.

Though the mémoires were written in 1968, almost 50 years after the events they are describing, the level of detail and clarity are impressive and the book makes for a fascinating read for anyone interested in finding out more about military communications before radio became the default means of information distribution.

It is gratifying to note that Lieutenant MacGregor received the military cross for his bravery.

In major cities around the World it is now unusual to find yourself in a place without a WiFi connection or two going for free. Coffee shops, bars, department stores and many other places now offer free WiFi to their customers. Normally all that is required is to enter an e-mail address and accept a set of terms and conditions and you are surfing gratis. For anyone roaming and facing extortionate fees for their data connection, these WiFi connections can be a godsend.

But there are still some places around the world, even in major cities, where WiFi connections are few and far between and top of the list are the various underground metro systems. To make matters worse, many metros are not only WiFi free zones but are lacking mobile phone coverage too. Thankfully this situation is becoming less frequent as operators (whether transport or mobile) decide to provide the infrastructure necessary to enable mobile coverage underground. Covering underground tunnels and stations is not difficult, but it can be expensive. It requires the use of special antennas and in many cases the laying of leaky feeder - a coax cable specially designed to 'leak' signals along its length thereby acting as a long antenna.

The London underground has long been an area devoid of any kind of broadband internet connectivity, but for the 2012 Olympic Games many stations (not the tunnels connecting them) were fitted with free WiFi by internet service provider Virgin Media. Since the games, the WiFi has no longer been free (except for existing Virgin Media customers) but coverage is slowly being extended.

If you want to know which stations have coverage, you could visit Virgin Media's station guide, or alternatively 'there's an app for that'... The Station Master app (unfortunately only for the iPhone at the moment) will let you know exactly which stations have WiFi connectivity and is updated regularly with information from people using the underground network and so often it shows stations that have got WiFi but which have not made it to the official station guide yet. As if to prove a point, at the moment Station Master is showing 123 stations with a WiFi service whereas the Virgin Media web-page only shows 120!



Not only does it show you where there's WiFi on the London underground but it also has 3D plans of nearly all of the central London stations (so you know which stairwell is quickest and easiest for getting from one line to another) and also will tell you exactly which door to stand at to get on the train so that you are in the right place to get to that stairwell or walkway when you get off the other end. For anyone who uses the London tube to get around, the app is a must have (even at GBP1.99). Of course you'll have to have a WiFi or mobile connection first to be able to download it in the first place!

Whilst Wireless Waffle is branching out into equipment reviews the time seems right to give a plug to the snappily titled TP-Link WR702N wireless N nano router.

What is it? It's a small (hand-sized) wireless router that can be configured to do a number of jobs. In essence it's a wired network connection and a wireless network connection in a single box that can be configured in a number of ways. For example:

1. It can add a WiFi connection to a normal wired network or internet connection.
2. It can share an existing wired internet connection with multiple devices or users.
3. It can extend the range of an existing WiFi network.
4. It can act as a WiFi client, to give a wireless connection to things that don't have one (e.g. TV set-top-boxes).

And all this in a case no larger than a deck of playing cards and at an amazingly low price.

The device deserves a special mention because of both its flexibility in being able to do a number of different tasks, but most importantly because of its usefulness. The only downside is that it can be fiddly to set-up (see the CNET review of the device for more info on this).

Imagine, if you can, being in an overseas hotel where there is a free wired internet connection but no WiFi and all you have to connect to the internet are your phone, a tablet and a laptop that's so slim and sexy that it doesn't have a wired network socket. You could turn on data roaming, but we all know how extortionate that is. You could get high, get moving, get naked and get clear to see if you can snag a signal from a rogue, unencrypted WiFi connection. You could wander down the street to the nearest coffee shop and hope they have WiFi. Or... you could have brought your TP-Link WR702N with you and plug it into the wired connection. Before you can say 'hey espresso', you have a ready made WiFi connection and both your phone and tablet are ready to update your Facebook profile!

Imagine moving into a new house to find that the WiFi connection covers every room except the kitchen. How will you read the morning e-newspaper over your coffee without WiFi in the kitchen? Simple, get your TP-Link WR702N and place it somewhere between the kitchen and your existing WiFi hub and before you can say 'special-k presto' you're back online.

Imagine discovering that you've missed the latest thrilling installement of 'Britain's Got Strictly Celebrity Antique Hunter On Ice'. Your satellite set-top-box has the option to run 'i-TV-Player-on-Demand' but it's only got a wired internet connection and you only have WiFi at home. Just break out the trusty TP-Link WR702N and before you can say 'tres fresco' you're streaming over-the-top video like a pro.

Finally, imagine trying to build a tower of plastic boxes that reaches the moon, to find you're a centimetre short. Just grab your TP-Link WR702N and put it on top and 'pay tesco' you've made it to the lunar surface.

Seriously though, for anyone who travels a lot and stays in hotels with no WiFi, who has patchy WiFi coverage at home, or wants to connect their blu-ray player to the internet to use Netflix, this little beauty does a great job and comes with the Wireless Waffle, 'Recommended Useful Broad Band Internet Signal Heighthener' seal of approvalness. Oops, that was supposed to be serious and look what happened. Maybe Wireless Waffle should just stick to being facetious.