What is all the fuss about?
"Isn't this just a bunch of radio hams making a big noise about a dying hobby?" and "Why don't you just use the Internet?" are just a couple of comments posted on forums in response to people raising awareness.
Every electronic device sold on the European market must past certain standardised tests to ensure it will not burn down your house, poison the neighbourhood, or interfere with the correct operation of other devices, such as radios; the latter part being referred to as the 'essential requirements'. These tests form part of the Electro Magnetic Compatibility Directive 2004/108/CE and they must be passed in full in order for the product to carry the CE mark. If they do not pass, the manufacturer is legally barred from placing the product on the market anywhere in the European union. The EMC Directive is an EU-wide law transposed into the laws of the members states and it cannot be ignored.
In-house PLT is classed as 'Information Terminal Equipment' (computer equipment), and must therefore be tested against the standardised test EN55022. This test ensures the device does not cause harmful interference to other radio services and users. You may have experienced total wipe-out of your radio from computer equipment being sold in the 1980s and early 1990s. It was for this reason that the EMC directive, and EN55022, was put in to place. One part of the test requires electronic devices to not introduce harmful levels of interference on to the mains wiring, which may radiate and cause harmful spectrum abuse (the blocking of radio systems from working correctly). This test is known as the 'Conducted Emissions' test and it has strict limits.
PLT manufacturers, whilst claiming compliance to EN55022 on their product's Declaration of Conformity, have chosen to ignore the 'Conducted Emissions' test and omit it from the standardised testing regime. See the Truth & Lies page for more information on this. Independent tests on PLT products show them to fail the 'Conducted Emissions' test for EN55022, yet the devices are left on the market in contravention of the law. When challenged, national regulators such as Ofcom, claim the products do meet the 'essential requirements' of the EMC directive and there is no case to answer; yet their own testing says otherwise!
Why has this happened? It appears to have started over 10 years ago when ADSL and Cable systems, used for the delivery of Internet access, were in their infancy and someone thought it might be a good idea to cut costs and use an existing infrastructure: mains electricity cables feeding every home and business across the European union. A commission recommendation, 2005/292/EC on broadband electronic communications through powerlines was circulated to member states. If one carefully reads the document, one can clearly see the document refers to Broadband over Powerline (BPL) and not in-house PLT devices. National regulators, such as Ofcom, seem to think otherwise and hold up this document as a reason for in-action.
European Commission mandate M313 has also been held aloft by Ofcom to suggest EN55022 has been thrown away and PLT devices do not have to pass its tests. This is plainly wrong, as anyone who reads 2005/292/EC and mandate M313 can see for themselves! All devices must still adhere to the letter of the 'essential requirements' as laid down in the EMC Directive 2004/108/CE.
Standards setting bodies CENELEC and ETSI, under orders from the EU commission, have been trying for over 10 years to establish limits to allow Power Line Technology to work. The latest is EN50561 and it is likely to be voted out by the national councils. Why? Because it is being heavily influenced by the PLT manufacturers who want a 30dB relaxation in testing limits to allow their products to work. Or, in other words: they want to legally obliterate the radio spectrum for good!
Who uses radio?
As our opening headline suggests, many in the pro-PLT camp like to ask why people want to use radio as a means of communication?. There are many of life's pleasures people take for granted in their every day world that rely on radio to operate; here is a small list:
- Television - Cable, Satellite and Terrestrial broadcasts all need radio to get the pictures to your TV.
- FM "stereo" and DAB radio.
- Mobile phones, DECT phones and 3G connectivity (inc. Bluetooth and Zigbee).
- Telephone exchanges in remote locations - rely on microwave radio links to connect people to the rest of the world.
- Safety of life services such as the Police, Fire Brigade, Ambulance (inc. Air Ambulance), Coast Guard and the motoring services.
- The military and security services.
- Town/shopping centre security services.
- Hospital paging systems.
- Air traffic control.
- Aircraft Navigation.
- Instrument Landing Systems.
- Automatic Identification System - a ship anti-collision system.
- Remote vehicle central locking.
- Taxi services.
- Citizens' Band radio.
- Private Mobile Radio (PMR446).
- Wireless Networking (Wi-Fi).
- Train safety communications (inc. Underground radio).
As a nation we are legally required to use the radio spectrum in accordance with internationally agreed limits. We cannot suddenly increase the transmission power of Radio 1 and force it on the rest of the world by wiping out their local radio stations. International agreements are drawn up at the United Nation's International Telecommunication Union.
ITU Radio Regulations article 15.12 states:
"15.12 Administrations shall take all practicable and necessary steps to ensure that the operation of electrical apparatus or installations of any kind, including power and telecommunication distribution networks, but excluding equipment used for industrial, scientific and medical applications, does not cause harmful interference to a radiocommunication service and, in particular, to a radionavigation or any other safety service operating in accordance with the provisions of these Regulations."
This is an international treaty obligation that the UK government through Ofcom must comply with. Through Ofcom's failure to stop the sale and use of PLT, the UK government is in breach of its international obligations to the ITU (a UN body).
The EU Commission and Ofcom both try to suggest that it is only amateurs and short wave listeners who are complaining about PLT. But many professional workers are raising their voices also, including the following:
NATO - report concludes that "These increased noise levels would have adverse effects on military communications and COMINT systems, and also outside the military community on any HF spectrum users that typically operate in low-noise regions."
BnetzA report on aeronautical - makes it clear (table 5-2) that existing PLT devices exceed the allowable level for aeronautical safety by some 50dB (100,000 times).
BBC report - concludes that "none of the limits proposed so far offers adequate protection to broadcast reception." http://www.bbc.co.uk/rd/pubs/whp/whp012.shtml
BBC R&D White Paper 195 : VHF emissions from PLT devices - First investigation of potential interference to broadcast reception.
The European Broadcasting Union issues views to prevent PLT interference.
The CAA has expressed concerns over PLT: INFORMATION PAPER by International Civil Aviation Organization
Our sun cycles through periods of quiet and periods of high activity, also known as solar minimum and solar maximum. The cycle typically runs for 11 years, although it can stretch for longer. During a solar-minimum (a period from which we are currently emerging) there are very few sunspots and the energy emitted by the sun is lower than during a solar maximum. Of interest to HF radio users is the Ultra Violet flux density; or the amount of UV energy hitting the upper atmosphere. This UV energy ionises layers of gas to create the ionosphere.
The ionosphere is a shell of electrons and electrically charged atoms and molecules that surrounds the Earth, stretching from a height of about 50 km to more than 1000 km. For users of HF radio, it has some very special properties. Frequencies from a few kilo Hertz up to approx. 50 MHz are reflected by the ionosphere and are said to "bounce" between the ionosphere and the ground.
This "bouncing" is known as propagation and is affected by the energy density of the ionosphere (which also varies between the day and night side of the planet). During solar minimum, the amount of UV energy is reduced, and this in turn reduces the energy density of the ionosphere making it less reflective to radio waves; thus HF radio is limited to the local surroundings (a few kilometres to a couple of hundred). During solar maximum, the amount of UV energy increases and this creates a higher energy density in the ionosphere making it highly reflective to radio waves. With a highly reflective ionosphere covering half the planet, a 4 watt Single Side Band transmission from the UK can easily reach Australia.
With the ability to reach half-way around the planet, Radio Amateurs are predicting massive problems with the use of PLT. As we emerge from a period of solar quiet, and the ionosphere starts to become more reflective, the radio energy leaking from the homes of PLT users will start to bounce and spread much further than at present. This may not seem a problem for a single installation, however, Ofcom have predicted 750,000 pairs are in operation and the combined radio energy from that many devices is going to light up the ionosphere above the UK like a Christmas tree. The UK, with the largest PLT install-base per square kilometre, is going to become very noisy and will make itself global enemy number 1!
Of course, this is a prediction. We have never before had to deal with such a wide swathe of spectrum abuse bouncing off the ionosphere and the results are anyone's to guess!
You can read more about the effects of the sun and the ionosphere at http://solarcycle24.com/
Why should I care?
Why should you care about causing interference to a small group of radio users? Why should you care that those radio users may be disabled and only have use of their Amateur radio or CB radio kit to keep in touch with friends and family? Why should you care that someone may have invested considerable time and money (anywhere between £100 and £10,000) in learning how to use radio correctly? Why should you care about the issues of a minority?
Lets put the shoe on the other foot...
Why should we care if your child goes missing and you need people with radio to help find them? Why should we care if you need urgent medical assistance, but the Ambulance service radios are jammed? Why should we care if our legal radio equipment wipes out your television, FM radio or DAB radio? Why should we care about you if you do not care about us?
We, the radio users of HF are trying to bring the issue of PLT to everyone's attention before it is too late! It is in everyone's interest to ensure the radio spectrum is protected for legitimate and legal users and not be ridden over roughshod by big business only interested in making a fast buck!
The radio spectrum is a natural resource. We tend not to think of it this way since it is not a tangible substance which will run out one day, is it? -- Is it?? Well actually it is a finite resource. There is only so much information you can pack into a signal before that signal starts merging with another. The radio spectrum is full - overflowing actually. This is why to transmit almost anywhere requires a license - so the administrations of any country can control the use of the spectrum to prevent interference and maintain sufficient order and quality to receive a service.
EMC Engineers (the guys who make sure electronic devices do not interfere with each other) have been warning about employing this technology since the 1990s. Now it is in mass production and one company, BT (British Telecom) are distributing PLT adapters with their "BT Vision" product. Although BT are not the only supplier they are by far the most expansive. If Ofcom were to admit that the technology should never have been allowed into active service, who picks up the cost? For this reason Ofcom continue to claw at every hope that somehow they can 'prove' the technology falls within acceptable limits.
Let us paint a picture.
In this current era we as citizens have become acutely aware of the threat of terrorism. There is something about it in the news numerous times each week. Remember back to that fateful day in September 2001 when two jet airliners flew into the twin towers of the World Trade Centre? What is not commonly known about this event (but is easily verified) is that when the towers collapsed, they took with them considerable mobile telephone infrastructure - three of the major phone companies had their transmission equipment and aerials on the North Tower and when this collapsed, the phone network crashed.
The Radio Amateur community mobilised and used their considerable knowledge and expertise, but most importantly their radios, to coordinate and support the many services which were overwhelmed. Indeed, this is not an isolated example - whenever and wherever there is a disaster, the Radio Amateurs are there to provide support and infrastructure when normal channels of communication beak down.
What if they could not hear? What if the frequencies were all jammed up with interference? This has happened. In Linz, Austria in 2007 a disaster relief exercise was rendered useless by PLT interference. It is fortunate this was an exercise and not a genuine emergency. Imagine for a moment if it was your wife, girlfriend, mother, father, brother, sister, husband, son or daughter who's very life depended on getting that message out? Ofcom, the UK communications regulator states in their September 2009 bulletin that "...there does not at present appear to be any significant public harm arising from this situation...". Quite so, not yet.
This of course belittles the countless thousands of users around the country who can no longer hear their favourite radio channel, or who's enjoyment has been decimated by the invasive interference which PLT inevitably causes. It pays no heed to the persistently growing population of migrant workers who may well rely on Shortwave broadcasts to keep up to date with the daily events of their home country. At the time of writing, the number of complaints reported on the Ofcom website is a long way from being accurate - a recent Freedom of Information Act request has determined this much. Indeed, PLT is currently now in pole-position with regard to the number of complaints received by Ofcom's interference team - and it is rising quickly.
In September 2009, in the same bulletin Ofcom concluded "no significant public harm", they also announced that due to Stakeholders' concerns regarding PLT, Ofcom had commissioned a report into the potential effects of the technology. If Ofcom were so certain that there is no issue with the technology, why commission a report at all? They are, after all, the experts? Well it seems not and this point will be further explored on the rest of this website.
Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers.
We are sure you read this statement the same way as we do: We all have the right to interference free communication, be that un-censored Internet or noise-free radio. So why are PLT manufacturers free to trample over a medium that has been established for over 100 years?
Why have I not been affected?
The current range of PLT, both UPA and HPA models, only utilise the frequencies of 2 to 30MHz. This is known as the High Frequency, or the HF part of the radio spectrum (defined officially as 3 to 30MHz). This band is primarily used by the military; for long range aircraft communications (military and civilian); for long range marine communications (military and civilian); for long range audio broadcasting (aka Shortwave broadcast radio - used where VHF FM has no reach); as well as Amateur Radio and Citizens' Band radio (the latter two using tiny parts of the HF spectrum by comparison). These are niche users whom you may not come across.
There is however, a new batch, using the recently launched Gigle chipset. These HPA based devices utilise frequencies up to 300MHz. This is the VHF part of the radio spectrum and this contains many more users than HF. PLT using VHF has been demonstrated wiping out FM Stereo and DAB radio. The VHF allocation also contains safety of life services, such as Air Traffic Control and the Ambulance service (in the UK, unless they switch to TETRA). If you have not been affected yet, you will be in the future!
Are there other interference sources?
Yes. See our sister site UKQRM for more information.
Page updated: 15th August 2021
What is PLT?
Why the fuss?
What can I do?
Shame on you!
EN55022 | prEN50561-1:2012 | Legislation | Truth & Lies | Adjournment Debate
Guest author DJ5IL: The Trojan Horse of the PLC-Lobby: FprEN50561-1 | Doomed to Fail: FprEN50561-1