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YouView recommends radio hams' pet peeve

IPTV outfit's set-top box to prompt powerline usage surge?

Radio hams with a downer on powerline Ethernet are set to be even more upset by the debut of YouView. The IPTV platform is recommending the networking-over-the-mains technology.

YouView is currently running a closed trial of service. Trial support documents seen by The Register recommend punters whose broadband box is more than a Cat 5 cable length from their TV should bridge the gap with a pair of powerline adaptors.

YouView's platform combines live Freeview and Freeview HD viewing with online catch-up services from the BBC, ITV and Channel Four. Digital TV and IPTV programmes are listed in a common EPG.

Without net connectivity, there's no IPTV, so linking the YouView box to a broadband feed is essential. Future YouView set-top boxes may, of course, incorporate Wi-Fi, but for the moment a fair few folk may need to employ powerline.

Short-wave radio users won't like that. They say powerline kit fills their favoured band with noise. Some adaptors do, though whether over such large distances as naysayers claim has yet to be proven.

YouView's launch is expected to be announced at an event the organisation is hosting on Wednesday. Of course, YouView was supposed to have debuted two years ago. Back then, there weren't the number of BBC iPlayer gadgets and TVs that there are now, so YouView may not prove as popular as it once might have done.

In which case, its launch now may prompt fewer fresh powerline installations that hams fear. ®

Anonymous Coward

You want to hear about crap?

"My homeplug doesn't radiate on my house's wiring, therefore they must all be OK" (dogged @ 13:58)

Utter crap.

"I don't complain about all these radio hams messing up my HP networked systems, so why should they complain the opposite."

Because their licensed kit generally conforms to the necessary regulations and is required to coexist with other stuff in a realistic environment. If it doesn't, it gets shut down, banned, or worse. If only the same could be said for the PLT kit.

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@A.C. -- Re: I'd dump my HomePlugs tomorrow...

"Give me a break, change the record."

Not Bloody Likely!!

The more you ignore us, the more annoying we'll become!! BPL/PLC/PLT/HomePlug is an environmental issue--just it's about the radio spectrum environment (but the rules are the same). Like other rabbit Greenies, we'll whinge, annoy and irritate you until all BPL/PLC/PLT/HomePlug spectrum hazards have been regulated out of existence. We 'Greenies' have more persistence, tenacity and resilience than you quiet-lifers, that's why we'll eventually win.

Get used to the fact there's a war in progress and that you spectrum polluters are clearly in our sights.

"Oh, and I stopped reading after your first paragraph."

Correct, you're clueless about Spectrum Management because you've never read anymore than a headline about the subject. Whilst somewhat debased now through government downsizing and outsourcing, but once an important branch of government, Spectrum Management's raison d'être is to protect legitimate users from you spectrum polluters and to see that the radio spectrum is efficiently used by ensuring minimum mutual interference. BPL/PLC/PLT/HomePlug is NOT a legitimate radio service but a spectrum polluter, and thus it will always be a key target of spectrum environmentalism. Spectrum vandals won't get off scot-free! Got that? (Better not forget it either.)

Get it into your thick head that the BPL/PLC/PLT/HomePlug issue is not only a radio amateur issue, it equally concerns many other legitimate users who share the radio spectrum. Moreover, the legitimate users of the spectrum share it in a precise and orderly way and they've done so according to ITU rules for going on a century--unlike BPL/PLC/PLT/HomePlug interference which pays no heed to the rules--any rules, except those of self interest.

I don't approach this argument as an amateur; thus it's unlikely I'll regularly experience the deleterious effects of HF band interference caused by BPL/PLC/PLT/HomePlug, rather I come to it as one who has previously spent time on spectrum management committees. From that perspective, if anything, amateurs could be perceived as more trouble through the less predictable nature and variability of their service but in practice this was never the case.

The fact is that effective spectrum management is and has to be one of the ultimate forms of agreement and cooperation, and over the past century or so this has been mostly the case. Not only is Spectrum Management a highly technical matter but it also involves very different and conflicting issues, both technical and political. Coherent (message-producing) transmitting devices (TV, radio, communications, amateurs etc.) must coexist in close proximity to sensitive receiving devices with almost no mutual degradation being caused to each other's service. Protection from non-message-producing transmitters (noise-producing motors etc.) is axiomatic and thus legally enforceable. It has to be thus if radio communications is to work at all. Add to this mix the intense politics of competing demands for scarce spectrum resources and thus we end up with the highly complex animal that's Spectrum Management.

Into this complex environment comes BPL/PLC/PLT/HomePlug. No, it's nothing like wireless and WiFi which compete with and are allocated spectrum and obey the spectrum management rules as do all other wireless services. Rather, BPL/PLC/PLT/HomePlug obeys no spectrum management rules whatsoever. Intrinsically and by design, it cannot because its signal is fundamentally different and cannot comply on technical grounds (in that it was designed to travel in a bidirectional manner over wires and NOT be radiated). Thus, whilst its signal is coherent within itself, BPL/PLC/PLT/HomePlug is little more than wideband random noise when compared to normal wireless signals that are sent over the highly regulated RF spectrum--i.e.: those which comply with international regulations.

BPL/PLC/PLT/HomePlug was NOT designed to radiate into the spectrum but is does so by virtue of the world's biggest antenna to which it is connected--the powerline grid. The power grid is the means of network distribution for PL/PLC/PLT/HomePlug systems, but to HF signals, thousands upon thousands of miles of power cable strung high into the air are also an enormously effective antenna.

In radio spectrum parlance, BPL/PLC/PLT/HomePlug is a 'DC-to-daylight', broad-spectrum incoherent signal. In electrical engineering parlance it is nothing more than electrical noise, exactly that--unwanted ELECTRICAL NOISE/INTERFERENCE (RFI). Facts are facts, no amount of dressing up can or will ever change that.

No matter, how its advocates try to dress it up, BPL/PLC/PLT/HomePlug cannot be made into anything other than what it is. Attempts at making it comply to certain 'standards' such as restricting its output amplitude/level or notching its output over particularly susceptible bands/frequencies (for example, some amateurs bands) are nothing other than painting over rust, as its signal remains fundamentally incompatible with spectrum management norms.

Nothing can disguise the fact that BPL/PLC/PLT/HomePlug is an extremely wideband, highly complex signal that's rich in high-order harmonics and which spans over many, many octaves. Moreover, as its advocates would try to have us believe, this wideband signal is supposed to coexist within an environment where whole bands are only a small fraction of an octave and where the very narrowband signals contained within them are only a few kHz wide.

To make matters worse, these 'incoherent' noise signals, having been fed into and disseminated by the world's largest antenna, effectively increase the RF spectrum's noise floor right across the planet. Increasing the noise floor has a widespread, profound, and detrimental effect on other radio communication circuits worldwide, as effectively all radio circuits require additional transmitter power to overcome the additional noise. Environmentally friendly it is certainly not!

A simplistic but reasonably realistic analogy of an increased noise floor would be if one were to add some black pigment to a tin of white paint. Later, adding various colour pigments to the now grey paint will still result in one achieving a substantial range of colours, however, all the light and delicate hues will be irretrievably lost. In essence, the signal-to-noise ratio falls for all other legitimate users of the spectrum when BPL/PLC/PLT/HomePlug's interference increases the noise floor across the planet.

In computer vernacular, BPL/PLC/PLT/HomePlug is effectively a virus which pervades most of the HF spectrum and much of the VHF, and the only effective way of totally eliminating it is to kill it off at its source.

Ultimately, there's no other solution other than to get rid BPL/PLC/PLT/HomePlug and replace it with proper engineering and technology. If you and other users of BPL/PLC/PLT/HomePlug-like systems think we RF spectrum environmentalists will eventually go and fade away, then, frankly, you're in for a big shock. If you think we'll stand idly by and let you ruin the spectrum, then think and think again.

We've only just begun, and rest assured you'll lose interest first. Just use proper engineering and we'll leave you completely alone.

Promise.

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Anonymous Coward

Re: Apples and Oranges

What's your specialist field, dogged? Mine is physics, electronics, RF propagation, that kind of thing, with a particular interest (from outside) in mass market systems. I am not and never have been a radio ham, RSGB member, whatever, but I do own two oscilloscopes. Now, moving on.

Are readers following BT's slow progress towards faster-than-ADSL broadband? I am, and have been for the last decade or more. (Other ISPs are available, and often better).

To get faster than ordinary ADSL, in a non-cabled area, it's fibre optics from the exchange to the cabinet, then the usual boring old copper the rest of the way to your home, office, etc. The copper bit uses a technology called VDSL - like ADSL, it's radio frequencies down the existing telephone wires. ADSL uses up to roughly medium wave frequencies, but in order to get the extra performance, VDSL needs to make use of more bandwidth, right up to shortwave frequencies. It has to do this over a network of cables that was designed (and mostly installed) decades ago with little intention of ever using it for much above 3kHz never mind 30Mbit/s. But because the RF spectrum in general is relatively clean, it works reasonably well much of the time (with exceptions).

As it happens the frequencies used by VDSL include the same shortwave frequencies that your beloved hams use.

And with powerline splatter all over those frequencies, not only will they be unusable by the hams, they'll be pretty much unusable for VDSL too. So in a PLT-equipped world you'll likely be stuck with basically ADSL performance until the Internet comes to your door on interference-free fibre. Don't hold your breath on that one.

Now, what was your point again. Or are you just keen on showing your ignorance (it's working well so far).

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Re: Radio Hams are full of crap

There are a number of reports that have been commissioned, and all of them found that when active and connected to a Line Test Network with a 6dB LCL the PLT adapters of all flavours are transmitting at 30+dB above the EN55022B limits, some at 40dB above.

Now, as of October 2011, all newly brought to market PLT devices *must* comply with EN55022B emissions limits, but there is a 6 month window in which the device has to be suspected, investigated, tested and found to be non-compliant.

Whether this regulatory nonsense can continue I don't know, the provisions in the new draft EN50561 standard will supersede EN55022B, but this is still a draft and there is a lot of resistance to the levels allowed because we all know that the adaptive notching approach is not going to be any use unless there are very strong local signals.

A pity that most of the antis here are all ACs and are not prepared to stand up and be counted. The mere fact that Ofcom had to be compelled to release their own PLT test report that was every bit as bad as those protesting had said is indicative that the market is being skewed.

I assume you'll all be telling me that the assault on my ears and the lines down my waterfall displays on HF are a figment of my imagination too.

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Re: Radio Hams are full of crap

What is RF diags kit? Your kit or your training is defective.

High speed data transmission requires radio frequency signals and you can't send high speed data down unscreened and untwisted wires without it radiating.

Power line communication modems are broadband radio transmitters, the only way they don't radiate (much) is if your particular mains wiring topology and length happen to be a crap antenna at the frequencies you are interested in.

As for microwave oven - lol. Didn't your training explain the difference between signals with wavelengths of 10s of meters and those of a few centimetres?

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