S.O.S – Save our Shortwave
Shortwave radio enthusiasts are up in arms about Homeplugs – and the local interference that they can create.
What is a Homeplug? These are used in situations where you need to run a broadband connection around your home, but you can’t, or don’t want to, use wi-fi. Homeplugs come in packs of two – a transmitter and a receiver, and use the mains wiring in your house to transmit data.
Homeplugs (also known as Powerline adapters) are becoming quite common, and are readily available from the likes of Maplin, Dabs.com and BT. They’re supplied by BT as part of their digital TV offering, BT Vision, for circumstances where it’s not easy to connect the BT Vision box directly to a BT Home Hub.
So, what’s the problem? Well according to the site UKQRM, these powerline adapters are causing significant interference between 3Mhz to 30Mhz, which is the band used to pick up shortwave radio, affecting reception of a number of shortwave stations hundreds of feet away from HomePlugs.
Just who uses Shortwave these days though? Well, apart from the overseas stations that you can get on shortwave, the band is used for marine and aircraft traffic, as well as radio amateurs and an International radio service called DRM (Digital Radio Mondial)
There’s an active petition to the UK Government to get these devices banned – see the Petition to save shortwave
UPDATE: We featured this story in Show 32 of our podcast. Got a comment? Please add it below.
(Thanks to Mike Carrington for bringing this to our attention)
Thank you for enaging with this issue.
Philip
G3TEX
Having suffered the terrible radio interference these adaptors create please let me make a few comments.
Most of them are powered 24/7 ,they generate just as much interference on standby.
The user has bought and installed the adaptors in good faith and will most likely not realise the trouble they can cause,sometimes up to several hundred metres away.
BT supplied Comtrend adaptors seem to give the most trouble. Have had 2 of these replaced by wifi after I complained to BT Headquaters and OFCOM, who classed the intererence as “Spectrum Abuse”.
I still have some interfence as units over 100 metres away are being received.
This Powerline system has been the subject of much controversy for a number of years.
To cut a long story short there is no way these devices can work satisfactorily for the user without causing radio interference nearby in spite of what the manufacturers claim.
House mains wiring is not suitable for being connected a wideband tranmitter/ receiver (which is what these adaptors are).
This is because the wiring and appliances are neither screened or balanced so inevitably act as a transmitting aerial of sorts.
Telephone wiring, which is normally properly balanced, now carries Broadband Internet, which is another sort of radio signal, without causing problems.
Interfering devices can usually be “cured” by simple filtering. Filtering Powerline Adaptors stops them working so the only solution is to replace them.
Suggest you contact Radio Society of Great Britain: http://www.postmaster@rsgb.org
Regards Paul Widger BBC Transmission Dept (retired)
Hi..
Firstly, a very entertaining show you produce, and good info/news too…
Anyway…
HomePlug adapters, Comtrends and others like them, are at best misguided, or even inapropriate technology for the problem they are percieved to solve.
As Mr Widger has said, domestic mains wiring, in fact mains power wiring in general is not fit for the purpose of carrying high speed data, because of all the uncontroled imballances and other disturbances..
There are also still many critical users of Short Wave, not least the Maritime users, Aircraft, Military and of course Broadcast, who themselves are trying to introduce DRM, a Digital SW broadcast system that could deliver good quality broadcasts over a very wide area. PLT/PLC/PLN (whatever you call it) will prevent reception of that quite effectively, and also could affect “safety of life” communications of other users.
If you look at the page I provided a link to, you can see graphicaly where Short Wave propogation is “Open” to, over a couple of days (today & yesterday) However, this little understood medium by todays public is being poluted by products that are at best “ignorantly” designed.
I’m not against technology, far from it! I work in a high tech industry, and have as much technology here at home (some say more so!) than many others, including Digital TV, Broadband, several computers, etc as so forth.
The thing with BT Vision, is that the Data over Powerline adapters, are *NOT* nesesary, there are much better (and lower cost) solutions to the problem of getting the data to the Vision box. The best performing and cheapest is a length of UTP network cable. If the BT Vision box had WiFi built in from the outset, there would be no need for the PLT adapters, or a cable.
I look forward to listening to your podcast (or Netcast as the US now say, after Apple started aiming the suits at people using the “Pod” word!)
Yours…
Dave Baxter.
PS: For PC and Network security news, check out Steve Gibson’s site http://www.grc.com, and the Security Now! netcast, every week.
The link doesnt show up as such. Here it is..
http://g8kbv.homeip.net:8008/ Short Wave Beacon reception from arround the world, received in North Bucks UK, in somewhat delayed realtime. (Updates each hour)
A map of the beacon locations can be found at…
http://www.ncdxf.org/Beacons.html
Regards.
DB
Show 32.
Thanks for airing this!
The wonderful enigmatic world of shortwave radio is under threat.
Shortwave radio has amazing properties allowing world-wide communications. Its been in use since Marconi made his first transmissions.
Many millions of people tune into shortwave radio everyday to
hear broadcasts from the USA, Russia, China, Canada, the UK and a
host of other world locations.
It is also used by radio amateurs who communicate with each
other over vast distances and at times of national emergency, it acts as a backup communications network, which is vital to us all.
It is a way of life for many who may be housebound, those who wish to keep in touch with events from their home country or who enjoy learning about language and traditions from other countries.
Shortwave radio frequencies sit between the top of medium wave radio
and the bottom of the FM broadcast band.
Shortwave is also inhabited by the military, aircraft, shipping, air-sea rescue and a host of other essential services, who are all licensed to use the frequency band.
Then came powerline adaptors! (PLT)
These gadgets have nothing to do with getting people on-line with computers.
They are used to transfer video and data from one room to the next without any direct connection!
They do this by sending wide-band shortwave radio signals along the electricity power cables of your house!
As these power cables were not designed for radio signals they act as aerials radiating the output of the powerline adaptors far and wide outside of the house.
Interference of up to 500 meters has been reported.
This is where the problem lies.
Just one house using these adaptors wipes out the reception of short wave radio in your local neighbourhood!
Even NATO has published concerns about these devices, and yet they are streaming onto the market here in the UK.
If one examines the regulations (Electro Magnetic Compatibility and Wireless & Telegraphy act 2006) these power line adaptors seemingly should not be in use, as there is no way they can meet the required standards!
So what is the EU and UK government doing about this?
Seemingly nothing!
UKQRM is a non profit users group. Working with many other radio groups to defend shortwave radio.
Ofcom the radio spectrum regulator here in the UK has finally acknowledged the problem and has set up a phone number for those affected to call in and report the interference.
http://www.ofcom.org.uk/radiocomms/ifi/enforcement/plt/
From RadCom November 2008
The RSGB has rerecently received a reply from Ofcom in response to a PLT complaint made almost 2 years ago.The Society has, in turn, expressed its dismay at the contents of this letter and has responded accordingly with a letter from the President. The following edited extract will help to show that The Society is not about to roll over and accept what ammounts to ‘shoddy service’ from the regulator.
“The Radio Society od Great Britain understands thatas the product in question was declared compliant in germany, Ofcom extended the usual courtesy of asking BNetzA to investigate as the home authority in the first instance. You say that BNetzA has investigated but decided not to take enforcement action but you have given no reasons. The implication is that you will be taking no further action. However as the product is available fronm UK outlets we do request that you continue to investigate our complaint of non-compliance, the fact that the German authorities have decided to take no action is not a bar to the UK doing so under the priciple of national subsidiary. The integrity of New Approach Directives is in fact dependent on member states acting where non-compliance is found. the procedure under Article 10 of the EMC directive provides the method by which Member States must notify the Commission of independent action.
” The Society submitted a detailed complaint case nearly two years ago and is stillawaiting positive action by the UK regulatory authorities. Yoi will appreciate that there is considerable frustration among HF radio users about this matter, many of whom are members of the RSGB. This delay, attributed to restructuring, is frankly deplorable, unprofessional and certainly does not reflect well on the neutrality of the administration or the Stated Duty of “Ensuring the optimum use of the electromagnetic spectrum” We believe the recent increase in reported intereference received from licenced radio amateurs and shortwave broadcast listeners alike and attributed to units from various manufacturers represents only a small percentage of those suffereing from this problem, with the majority not yet aware of what is causing the harmful interference to their reception.
“It is understood that a number of sufferers have already written to their MPs and MEPs in respect to this problem and no doubt these letters will reach your desk in due course. In the meantime we look forward to hearing the results of your investigations as referred to above and the pursuance of the ” enforcement policy in line with stakeholderss needs2″.”
I have little faith in any UK quango or authority looking after the welfare of private individual radio listeners troubled by interference.
For years I tried to get various agencies interested in taking action against pirate FM radio stations in east London which splash so widely they even block out BBC Radio 4 and other ligitimate stations.
The best response I had was a request to listen and report any identifiable advertisers they could approach and warn because the agency itself was understaffed.
Ofcom now seems to have streamlined that approach with an online form (saves them having to be in directy contact with the public, I guess, but the problem persists…
Following a discussion with another electrical engineer, I elected to test a set of the new Belkin F5D4076 (Gigabit Powerline HD Starter Kit). What I discovered came as a shock. The “old” PLT adapters are responsible for significant radiation from roughly 2 – 30 MHz and this is established fact identified from tests by Notified Bodies (contrary to what the PLT manufacturers state) and in one test highlighted on my site below, the level was 22,500 times the limit agreed by international Standards…
The Belkins named above, were found to significantly disrupt VHF Stereo FM broadcast and even more surprising, the new DAB service. But hey – PLT doesn’t cause interference does it? Think on.
Many of the UK’s EMC experts (highly respected engineers) were so appalled by the reality of PLT they formed a new ‘association’ called the “Summit Group” who’s only goal is to have PLT banned or forced to comply with the essential requirements, which is most certainly does not currently do.
If you have any uncertainty in your mind about the reality of this technology, please take a look at my YouTube video which demonstrates the F5D4076’s interfering with VHF Stereo broadcast and DAB. Once you finish there take a look at the real world of PLT with test results at my site. It’s not the bed of roses that the manufacturers make out…
YT Video:- http://www.youtube.com/watch?v=z3yVu5IfaEY
Belkin test results:- http://plt.g7cnf.me.uk/belkin_3.htm
Thanks for this entry in your blog as HF spectrum use efficiency is very important and deserves not to have it polluted by such devices. People using these devices have them plugged in and on 24/7. Surely this in itself is inefficient.
These devices still contribute to the level of noise as long as they are plugged in and on (albeit at a lower level when not transmitting data).
I note you feature Belkin PLT device in your header this is quite interesting as the latest device (Belkin F5D4076)using the Gigle chipset which now seems not only to use the shortwave spectrum but also the VHF up to around 300MHz.
VHF besides being used for Civil aviation, Marine and Business radio, it is also used for broadcast VHF FM and DAB radio. (also the 2M,4M, and 6m amatuer radio bands). Having viewed a youtube video at:
http://www.youtube.com/watch?v=z3yVu5IfaEY
the content of which I have no reason to doubt, I find Belkin’s statement regarding interference to be nothing other than totally at odds with what the field trial as shown in this video. It seems to raise many questions and I hope someone commissions a test at an independent accredited laboratory.
Many of the issues these devices raise have been well put forward at the following website:
http://plt.g7cnf.me.uk/belkin_3.htm
Just as a ‘rider’ to the above comments, there is a new product on the market now, (No names no writ) that operates over the frequency range of 3 to 300 Megahertz.
This piece of kit will wipe out FM broadcast radio, DAB, Air Traffic Control, Police, Fire, Ambulance, Business radio, and many other legal and licensed services, as well as the previously mentioned ‘short wave’ services. The first ones are creeping into the country now, and a few pairs have been tested and fail the requirements by a LONG way.
here’s the url –
http://www.youtube.com/watch?v=z3yVu5IfaEY
These adapters have destroyed my shortwave listening,I have constant noise for 3 to 30 Mhz, hundreds of pounds worth of radio equipment and I am unable to use it, Ofcom have let the HF and now vhf spectrum goto pot, they should be ashamed of themselves.
You might be interested to know that we recently interviewed the chairman of the Chelmsford Amateur Radio Society, and discussed the problem with Powerline (PLT) adapters.
You can hear our interview at https://www.frequencycast.co.uk/amateurradio.html
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