These are inherently illegal transmitters. They talk to each other without actual mains wire.
If they are properly tested for Radio Interference they fail.
Get some Cat5e cable.
When a vendor puts a colour-coded performance guide LED onto a powerline Ethernet product and admits that "best" throughput - the light is green, natch - is "greater than 80Mbps", you immediately realise how big a gap lies between the technology's reach and its grasp. Netgear's latest adaptor, the XAV5101 500 Nano, is labelled …
"They don't work unless they are plugged into the mains, so how can they talk to each other without mains wire?"
But they do. They only need mains power. Run one off a Generator, Inverter or UPS(unplug it after turning on) and with a reasonable 4 way socket strip extension cable and they will connect. The longer the "aerial" (extension cable) the bigger the distance.
The fuse box doesn't block it. They radiate very well from the lighting wiring.
You can get attractive skirting "board" that is concealed trunking and use a "router" to put slots under a door saddle to hide cable. A self adhesive trunking with clip on cover in a corner up a wall.
Running cable around outside of house too.
Convenience and lack of effort / imagination isn't an excuse to to flout international standards. These are ALL self certified using the wrong tests. They are ALL transmitters and ALL fail RFI testing when tested properly in a "real world" scenario and carrying data.
"Convenience and lack of effort / imagination isn't an excuse to to flout international standards"
Apparently it is, as it's exactly the excuse many are using, myself included, although personally I'd substitute "lack of effort / imagination" for "not really cricket if you live in a rented property where the owner has explicitly said no". Something, I imagine, that would apply to a great many people. But then why bother trying to understand that everyone may not have the same carte blanche to do DIY as you when throwing some lazy prejudice around is a lot easier?
Can you post some links to this skirting board trunking? I'm serious, I want to run CAT6 cable round my house but my landlord wouldn't want extra trunking putting in so something like replacement skirting board which looks neat with a couple of wall sockets would be ideal.
Then I've just got to work out how to get CAT6 to the garage under the house (without drilling holes) and into the bedrooms (again without drilling holes) :-)
Doesn't running cable outside the wall also require some of that UV protected cable or is it possible to protect the cable with something like electrical tape?
Cables run outside need to be UV resistant, otherwise eventually they go grey and powdery.
Black insulation tape would be time consuming and look very messy (I've tried this :) ) , you'd better make sure your insulation tape is UV resistant.
Best would be to run some plastic conduit, which makes a much neater job, especially when running more than one cable. This also helps me remember my happy younger days when I was an electrician.
@Rob If you do a google search for either "dado trunking" or "skirting trunking" you'll find lots of options out there.
If you want to run cable outside then you need to look for "external grade" cable. Won't be cheap, though. You may want to think about running CAT5e instead (unless you really need that 10G connection of course...)
external grade cable isnt much more expensive than normal stuff. It is quite stiff though. I love these powerline adapters. I have 4 of the original homeplugs. I used some netgears originally, they failed in a few months -wouldnt sync with each other. Bought a couple of noname homeplugs which have worked ever since. They refuse to work off 4 ways or on the same socket as a surge device but apart from that they DO jump circuits at the fusebox (downstairs, upstairs and extension). It wont reliably work to our garage (about 15m from the house and most likely on rubbish cable) so I had to use a directional wireless antenna bridge for that.
UV stabilised Cat 6 is no more expensive than ordinary Cat 6. You can buy arbitrary length off ebay for a reasonable price and at the end of the day there's nothing wrong with wiring the whole house with UV stabilised cable to avoid joins.
It's what I did with my 1920s property with solid internal walls; from the front room(s) outside, up the wall and into the loft, across the loft and back outside down the rear wall to the rooms at the back of the house. All neatly tacked and no worse in appearance than the old coaxial aerial cabling that used to make the same runs. (Going over the house used less cable than going around the exterior)
"But they do. They only need mains power. Run one off a Generator, Inverter or UPS(unplug it after turning on) and with a reasonable 4 way socket strip extension cable and they will connect. The longer the "aerial" (extension cable) the bigger the distance."
From my experience even a surge protector will throw these things off.
That's been my experience too. For years I've been using the old Netgear XE102 powerline adapters (14Mbps) for stuff whose speed I don't care about, like my Tivo updating it's schedule. But I've found the placement of the units is very sensitive to where the surge protectors are relative to the powerline adapters. The surge protectors look like a low impedance across the mains up at the RF carrier frequencies these things use. I've noticed my XE104's (85Mbps) to be even more sensitive than the XE102's.
Unfortunately they are or they would be seized at customs. Money talks.
They can interfere with DSL. BT engineers advised BT vision against using them.
Rather than blocking all sale Ofcom only insists on removal if there is an unresolved complaint. That is not a Spectrum Management policy. It's caving into the Gadget maker lobby.
They are very convenient to use but the actual data rate you get is much lower than the maximum claimed speed. I use the old standard 85Mbps units and get about 12Mb/s downstairs (where the router connected unit is) and 8Mb/s upstairs (on a different ring main).
That is plenty good enough for me (10Mb cable internet is all I have) so I haven't bothered upgrading to the newer standard. WiFi may be faster than that depending on how you place it. If you want to try them, you can get the old 85Mbps units on e-bay at low prices.
My mate fitted a pair of 500Mb AVs and throughput is 120Mb/s.
As the article says they add the upload/download speeds together to beef up the numbers and the encryption takes up a fair amount.
So you don't get 250Mb, you get half....
Oh and the new ones don't work with the old 85Mb/s versions.
Plus CFL lights interfere with the signal and these devices hate being plugged into Mains multiway strips.
Lastly they hate Mains filters. So plenty of problems to get over...
I have just set up a 3 point system at home using TP-Link 200mbps adaptors and it works fine (I have now ditched the 300N network).
I have connected BT Home Bub3 with Sky Box, WD TV Hub (Home Hub and TV are on different sides of the room) and PC (in a seperate room) and can happily stream video from the PC via the WD TV Hub and copy large video files over in a between PC and Hub in at least 1/8 of the time that I could with the WiFi if it actually completed without throwing the WiFi connection.
Whether or not there are many other users I am pretty chuffed with the results so far and will probably look to put one upstairs for the 2nd Sky Box at some time.
I recommend Homeplug to family members and friends, they've all installed Homeplug devices without any problems and been very happy with the results. I use 500-AV units and get about 120Mbps real world throughput, those I know that have also installed 500-AV get similar performance on decent wiring.
Fortunately, none of us give a toss about radio hams.
"Try as I might, I couldn't get the Netgear kit to interfere with either my DAB radio or the FM tranny I have in the kitchen. Well-behaving powerline adaptors are 'notched' to prevent them transmitting on used frequencies, and in all instances I've seen of powerline kit causing noise, the receivers have been placed near the adaptor."
Not a scientific test. What is your DAB and FM reception level?
What does it do on MW, Shortwave, VHF Low (42 to 76MHz), CB (27MHz)
When was it decided anyway that only FM & DAB is protected Spectrum?
It's not meant to be a scientific test. It's meant to look at a circumstance most of our readers are likely to be in: operating a powerline LAN at a home in which there are also radios tuned to mainstream UK stations.
I have seen demonstrations showing powerline interference to DAB and FM, but I have never seen it demo'd across a range of products. So, was it a faulty adaptor, a duff product line or symptomatic of PL adaptors in general. I've seen no evidence to confirm the latter.
I've also yet to see any evidence that the interference, where present, reaches distances that really will impact other radio users to any greater distance than the same room, or produces any greater impact that all the other general interference on those bands.
I am not a radio engineer, though, so I keep an open mind. If it's clearly demonstrated that there's a real problem here, not a few folk getting annoyed because they think there's a problem, Reg Hardware's attitude to these gadgets will change.
Regarding DSL interference, I'll be honest: I can't comment - I don't use ADSL.
http://www.ban-plt.co.uk/ contains all of the reports Ofcom tried to bury, but were forced to release by the Information Commissioners Office. It begs the question: If PLT is such a benign issue, why are government organisations covering up reports they commissioned in to the effects on the radio spectrum? Why do Ofcom keep saying they can introduce a Statutory Instrument to effectively curtail interference from PLT, yet fail to do so?
The simple fact remains: These devices, and many Switch Mode Power Supplies, Panasonic Viera Plasma televisions and a host of other electronic crud, are flouting the EMC Directive in order to make a quick buck and the UK national regulator (Ofcom) and various government departments (BIS, DMCS) are complicit in allowing this to happen. If you continue to support PLT manufacturers, plasma TV manufacturers, and assorted crud mongers, you cannot complain when everything in your house fails to work due to unacceptable levels of EMC interference!
You seriously expect me to believe relatively small companies like Devolo in Germany, and D-Link and Netgear in the US have so much clout with Ofcom that they can get the anti-powerline evidence supressed?
Gimme a break.
There's no mileage whatsoever for Ofcom in doing anything to conspire against radio users to keep powerline kit makers happy.
And let's say they did ban them. People would still use them, and, like low-range FM transmitters a few years back, there's nothing they can do about it because actually they don't bugger up licenced radio users' spectrum.
Well actually these things definitely do bugger up spectrum used by licensed users, particularly that used by SW broadcasters where they are not notched.
As of October 2011 these devices newly placed on the market must meet EN55022B:2006, this is the standard which Comtrend and Devolo have been found to exceed by 40dB.
The reason Ofcom won't take action is because they are simultaneously responsible for both revenue generation from RF spectrum and for protecting it against interference. So they're desperately trying to wriggle out of any commitment to taking strong action as otherwise they may end up before the Euro-beak for affecting the free movement of goods within the EU.
If anyone discovers that new PLT devices are still radiating excessively, take action quickly, you have 6 months from the date they are placed on the market to complain *and* to get the complaint agreed.
IIRC, when the fuss about these started, most of the problems (and indeed most of the devices in the UK) were the very noisy Comtrend ones handed out by BT with their various broadband/TV offerings. To compound the problem, punters who didn't use them themselves frequently flogged them off for pennies on ebay, making them one of the cheaper ways to get faster spec kit on the cheap. Naturally, loads of people bought them up. The early ones caused sufficient problems (including catching fire occasionally I think) that even BT admitted there were issues and replaced them on demand.
Small powerline providers may not have much influence with Ofcom, but BT certainly have more clout in Riverside House than Matthew Corbett did with Sooty.
Part of the problem is with the certification process, which works on the principle that if a device is certified emissions wise in one EU country, it counts for them all. So those wanting to pimp flaky kit head straight for the weakest links for the paperwork.
I've never had any issues with mine, even listening to shortwave and MW, where I get more crap from my Wacom tablet if the radio's too close, and in the past from a badly built imported TV next door that also took out my ADSL intermittently for 2 months.
"You seriously expect me to believe relatively small companies like [irrelevant]"
No. The names of the small companies are irrelevant.
What drove (and is driving) PLT in the UK is its use by BT Vision.
You seriously expect anybody to believe that Ofcon would take on any significant part of BT, regardless of who was actually right in technical and regulatory terms?
In a fight between BT Vision marketing at BT HQ, vs the BT DSL design geeks at Martlesham and the better BT/Openreach DSL support technicians in the field (the two groups who actually best understand the reliability implications on xDSL of misbehaving spread-spectrum-polluting electrical equipment such as faulty power supplies and allegedly working PLT devices), you seriously expect the technical and regulatory concerns to be taken seriously? When BT Vision revenue is at stake?
The material which Ofcon have been forced to release makes it quite clear that BT's use of powerline technology contravenes a variety of rules and regulations, and that Ofcon understood that.
Rather than require BT to address the issues (which would basically have forced BT to withdraw their "plug and go" product), Ofcon chose to try to keep the issues quiet.
It may be convenient to sweep these facts under the carpet. But they remain facts.
Funnily enough, I've powerline networking (5 nodes), ADSL, a Panasonic plasma, various PCs with SMPS and a load of hi-fi kit with (very) high power SMPS (which I know from being involved with the design that they behave a little bit naughtily, but they did pass compliance testing!), DECT phones, a microwave and a Goblin Teasmade - a perfect storm from what is being described in this thread.
Amazingly though it all seems to work perfectly. o_O
Have you heard the expression "absence of evidence is not evidence of absence?"
Quite a lot of people smoke and many stay alive for quite a while.
But in general, statistically speaking, smoking is quite bad for you.
Quite a lot of people use PLT devices and many see no problems (though others may suffer their from their emanations and those affected will almost certainly not know where to investigate).
But in generally, statistically speaking, PLT is bad for the cleanliness of your radio spectrum.
Today's radio spectrum is used for more than just what used to be called radio.
E.g. xDSL works using radio frequency signals down the telephone wires. Although telephone wires weren't designed to have RF of any kind sent down them, they are generally intended as a balanced pair which means in general DSL works remarkably well, both in terms of not radiating signals which interfere with anything else, and in terms of being reasonably resistant to incoming interference.
PLT, on the other hand, sticks significant quantities of wideband RF down wiring which was not designed for carrying RF, wiring which makes not attempt at being a balanced pair, and which consequently and inevitably radiates like crazy.
All of this is written down elsewhere by people who understand it far better than me. Even if you don't like the tone of the BanPLT folks, there's plenty other stuff in plain unemotive technical language for you to read in the documents Ofcom wanted you never to see.
I'm with Tony - similar (empirical) experience here; I use a mix of Devolo and Zyxel devices (AV) and haven't had any interference problems with DAB or FM & LW (rarely use MW). I also have ADSL broadband and haven't seen any problems there, either.
That said, I know the wiring in the house is reasonably modern and tidy - I rewired the place myself when we moved in. The thick walls in the house make using wireless throughout awkward without putting several routers around the building, so Powerline is a good fit for me. I can even get a usable link down to the garden shed & garage, very handy when needing to hide away :)
> I'm with Tony - similar (empirical) experience here
Me too. I've got four of these, all no-name eBuyer specials, forming two networks. Two link the living room kit (Blu-ray etc.) to the upstairs network where the Astaro gateway and NAS are, the other two link the Astaro to the DSL modem downstairs.
ADSL still works, so does DAB and FM. The radios in the taxis that sometimes park over the road cause more interference.
I wonder whether people are mixing these adapters up with broadband over power line? That used the national grid for broadband distribution, and was proved to cause interference.
To be honest Tony I am astonished that you say this, there are plenty of documented reports of PLT interference being audible many hundreds of metres away from its source, in some cases this is because it has made it past the domestic premises meter and fuses and has energised nearly streetlamps. It's a particular problem where the devices are not notched, so the short-wave broadcast bands suffer very badly from it.
Both UKQRM and the Ban PLT sites have reports from accredited EMC laboratories about PLT device failures according to the EN55022B standard, new PLT devices must meet the 2006 version of this from October 2011 onwards or they face being removed from sale.
EMC has long determined that a maximum distance for interference is 10m, so allowing devices that radiate over potentially 100 times that distance is a bad thing and should never have been countenanced.
"I've also yet to see any evidence that the interference, where present, reaches distances that really will impact other radio users to any greater distance than the same room, or produces any greater impact that all the other general interference on those bands."
Then you are not looking.
Someone will come up with links (I don't have time right now).
There is a youtube video of two "ring mains" in a field. No electrical connection, just free space. The PLTs connect. The wiring is optional.
Like it or not, these things are unlicenced (and unlicenceable) transmitters.
The BT DSL people did say no to PLT for BT Vision. The Vision marketing people overruled the DSL technical people.
VDSL (BT Infinity etc) is likely to be even more sensitive to spread spectrum pollution from PLT than today's ADSL and ADSL2+ is.
It's not rocket science.
Did similar tests a few years back when the standard was being worked out.
By using a radial spur, blocking filter and appropriately terminating* the mains wiring at both ends we managed to get a conducted emissions pass, and radiated didn't fail by much so could plausibly be sorted out.
However, the moment we used a ring final circuit (ring main) it failed quite spectacularly as this turns it into a loop antenna.
Notches work fine for avoiding radiated interference with specific other users, but you can't notch out everything so they will always squash somebody.
Put another way, it may be workable in much of mainland Europe because they mostly use radials, but it cannot work in the UK because we mostly use rings.
*Although the termination network drew more than half a Watt...
"the moment we used a ring final circuit (ring main) it failed quite spectacularly as this turns it into a loop antenna."
What kind of mains wiring configuration should be used for testing any kind of mains powered device for CE certification?
What kind of mains wiring configuration is generally used to allow PLT devices to get their CE certification?
How does the PLT test configuration relate to the configuration in which the equipment will actually be used?
Excellent question, and one to which I don't know the answer.
When I was doing these tests there weren't any "CE" EMC standards for PLTs, so we used the standards for normal PC equipment and looked at the complete point-to-point link over twin & Earth as being the "device under test".
- This also meant that every PLT shipped at the time was completely untested, the manufacturers claiming that as there was no "PLT" EMC standard they didn't need to meet anything.
We also looked at blocking PLT domains from each other - it needed seriously big blocking filters, and coupling between adjacent wiring easily bypassed it so we came to the conclusion it simply couldn't be blocked in any cost-effective way. This was before encryption as standard in PLT devices, so it's clear the manufacturers have realised this as well.
I gather that there are now standards for PLT, however I haven't read them - standards being very boring and PLT is not my day job.
"What kind of mains wiring configuration should be used for testing any kind of mains powered device for CE certification?"
They use a device called a LISN (see http://www.ban-plt.co.uk/tests.php for pretty pictures of how devices are tested) which creates a "clean" mains source which can be tested. Real-world testing in a domestic property would be tricky due to the amount of noise present from other devices. It is ironic that for PLT to work correctly, every other device attached to the mains must comply with the EMC regulations and not introduce noise. When noise is present, PLT fails to function correctly!
"What kind of mains wiring configuration is generally used to allow PLT devices to get their CE certification?"
To gain CE certification (which is worthless!), most PLT manufacturers have used the 'Technical Construction File' (TCF) route to validation. This is where a Notified Body approved to test to CE standards can issue an opinion that the documentation presented before them should result in a product complying with the requirements. At no point is the device actually tested. Result: Gaping hole into which companies can pour electronic junk! For some considerable time, Comtrend PLT devices were being shipped by BT Vision with a totally invalid Declaration of Conformity, yet the bodies responsible for policing this took no action.
As PLT is Data Terminal Equipment (DTE) it is supposed to be tested against EN55022 - the standardised testing for computer equipment. If tested correctly, all PLT devices fail the 'conducted emissions' test due to them blasting high levels of Orthogonal Frequency Division Multiplexing (OFDM) signals down the wires. This act in itself would not be a problem were mains wiring designed to handle radio frequencies, i.e. it was twisted, shielded, etc.. As it is not designed to handle radio frequency energy, it acts as a feeder and radiates the signals accordingly.
Compliance with EN55022 is voluntary, and PLT manufacturers have been trying to confuse politicians (not hard!) and push for their own "standard"; which is now being proposed as prEN50561. This "standard" seeks to increase the limits at which RF interference is classed as unacceptable. If this "standard" is accepted, it will destroy everything EN55022 seeks to protect, and it will no longer be the disgruntled users of the HF radio spectrum that will be annoyed. All radio frequencies will be fair game and you will not have a leg to stand on!
"How does the PLT test configuration relate to the configuration in which the equipment will actually be used?"
The testing environment is nothing like the domestic mains environment, which is full of noise, voltage and phase variations. The test environment is also usually carried out over short runs, whereas the domestic mains wiring looks like a series of aerial feeders, each with their own frequency response and radiation patterns. See http://www.ban-plt.co.uk/reports/RA-report-house-wiring.php to see how well mains wiring in the UK can act as an aerial.
There are plenty of adaptors with pass-through power, from almost all of the manufacturers of this kind of kit, eg.
Yeah, the previous generation of Netgears were shocking - I ended up RMAing four separate adapters over seven months due to them cooking themselves. Performance was highly variable too.
Bought a set of Devolos and have had near perfect operation in three different flats over the three years since. Added a third point and everything still works well - I find I need to turn em off and back on again about every 3-4 months when they decide to lose connectivity, but I can live with that.
"Try as I might, I couldn't get the Netgear kit to interfere with either my DAB radio or the FM tranny I have in the kitchen."
Think yourself lucky the Gov snoop infrastructure isn't in place yet. You keep some poor gender-confused cow locked up in your kitchen, attempt to assault her with items of networking equipment and then write about it on a public web site?
You are bang-to-rights, sir!!!
2.4ghz is a dead technology thanks to every house using it, soon 5ghz will go the same way once 802.11ac is in every house taking up all the channels. So proper cat5 it is unless you physically cant or dont want to run a cable, for one device, its not worth it. These mains plugs are very handy and I can run full HD streaming over them so I am happy.
Except for phones, tablets etc without cat5e sockets on, and the fact that it's rather annoying having to trail a cable for your laptop back to the wall, that's why they have batteries...
I agree 2.4GHz is problematic, I have had to fit enormous aerials to my Netgear Prosafe just so my phone can pick up reasonable signal, but the 5GHz is currently clear and has much wider spectrum to use, the only problem is the low penetration of it which ruins the propagation to my laptop/media PC when there is a few walls.
I use powerline from my router/comms core in the living room to the distant (I say distant, I mean 10m) because the wireless is so problematic. I would drape cat5e around but the mrs won't have it, and the landlord won't let me bury it in the wall so what choice do I have?
When I finally get to buy I will definitely be running cat5e to every room.
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