PLT chair: UK Radio Society is 'living in a dream world'
UK hams face down EU over powerline networking kit standard
The chair of the EU committee on powerline networking has responded to the Radio Society's call to arms, claiming that every minute of filibustering pollutes the radio spectrum more.
The Radio Society of Great Britain reckons the new standard, prEN 50561‐1, will water down existing requirements, opening the way to greater spectrum pollution, and has asked members to lobby their local representatives. But Ronald Storrs, Chair of the committee defining the standard refutes that, claiming it’s the RSGB who are risking the airwaves with their pointless protests and inflexible attitude.
The problem is that sending data signals over unshielded mains wiring, as powerline kit does, generates radio interference, and as the manufacturers push to increase speeds that interference is spreading into the frequencies used by the rest of us.
That, says the RSGB, is unacceptable, as EN55022 (to which all kit bearing the CE mark must conform) requires that devices don't generate significant interference. But, say the device manufacturers, our kit isn't generating the interference, the mains wiring is, and in many homes the wiring is sufficiently shielded that no interference is generated anyway, so we'll continue to sell our devices legally.
Those manufacturers have survived several legal challenges, and in the UK Ofcom has taken a backseat, saying it can't do anything as the devices themselves aren't radio transmitters so fall outside their remit. Ofcom says it's waiting for prEN 50561‐1, which will apply to powerline tech, but it's been waiting some time on that score.
Ronald Storrs agrees that PLT kit is generating unacceptable interference, but reckons that every day there isn't an applicable standard more unrestricted kit is getting into the marketplace, and the intransigence of UK radio hams isn't helping:
"Today's equipment has no restrictions" he told us, "so bad as it might be [prEN 50561‐1] is a huge improvement".
Storrs reckons having a standard in place also means it can be tweaked later, but having no standard means nothing can be done. Once passed 50561 requires devices to reduce their transmissions to the minimum needed, as well as switching off when no data is passing over the network. It also requires PLT kit to be "notched" to avoid using frequencies which have been identified as protected – and to detect and avoid busy bands dynamically.
Dynamic notching is complicated, and the RSGB has argued in the past that it often fails, even static notching has been shown ineffective as it is often poorly implemented and signals stray from where they should be. But while the RSGB argues that this proves notching is pointless, Storrs contends that once notching is part of the standard, then poor implementations can be addressed and rectified – but until then the manufacturers have a free hand.
Which is why, according to Storrs, the PLT manufacturers have been dead set against the standard, and why it has the support of the International Amateur Radio Union - which leaves the UK hams standing alone against the EU.
The RSGB calls for an outright ban, claiming that such devices breach EN55022, but that approach hasn't worked so far. If Storrs gets his way, then by the end of October we could have a new standard for PLT kit – one which can be enforced even if it's not as draconian as some would like. ®
PLT must be tested against EN55022 as it is Information Terminal Equipment, or ITE. The EU have stated that EN55022 is the correct standard to test against, so PLT manufacturers are lying on their EMC Declarations of Comformity and stating they pass EN55022 part A - which is for Industrial use only - will cause radio frequency interference. For domestic use, they should be tested against part B. This calls the whole DoC and CE system into question and renders it completely worthless!
Irrespective of EN55022, PLT must also pass the 'essential requirements' of the EU's EMC Directive 2004/108/EC; namely that it does not cause undue interference and stop a radio system from working as intended. The 'essential requirements' apply to all devices places on the market and PLT is no exception to that rule! prEN50561-1 cannot overrule the 'essential requirements', which it is seeking to do!
It should be noted that those driving prEN50561-1 through CENELEC are primarily from the PLT manufacturers. They are attempting to stack the deck in their favour and if prEN50561-1 becomes a standard, everything EN55022 stands to protect will be destroyed. Once that happens, other manufacturers will want to relax EMC rules for their products, and before long, all of you bleating on about Hams being a bunch of selfish <insert expletive here> will find your precious Internet connection dead thanks to interference from other electronic devices! Many of the proposed solutions for prEN50561 (smart notching, dynamic power control) either do not exist or are patent encumbered, so how can a standard for testing/compliance be produced when much of it is pie-in-the-sky?
What will it mean for you? Whilst the internationally agreed amateur radio bands and the CEPT Ciitizens' Band allocation will be protected by notches (a tacit admission that PLT creates radio interference), the rest of the HF band will be wiped, so if you like using ADSL/VDSL, listening to shortwave radio, or you need to communicate with aircraft over the Atlantic, or ships out at sea, you can forget it!
So I can now legally import and sell GPS jammers, etc?
The device itself isn't generating any interference; the antenna it's connected to is. And it's not my fault if the antenna isn't "sufficiently shielded".
Ofcom can't do anything as the device itself isn't a radio transmitter. It's not my fault if some miscreants create a transmitter by connecting it to an insufficiently shielded antenna.
Where do they get the idea that PLT isn't a radio transmitter
Of course it's a transmitter, it's generating radio frequency energy deliberately on its output pins. The only part of the equation missing is an aerial, and your mains circuit provides that. How long would it take them to jump on pirate radio stations if they weren't using an aerial, but were wiring their transmitter to a bit of pipe.