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Could Broadband Over Power Lines be Dangerous?

CmdrTaco posted more than 10 years ago | from the everything-else-is dept.

The Internet 240

falconfighter writes " Broadband over Powerlines, once touted as the solution to many internet problems (developing 3rd world countries, etc.) has a new hazard. The system basically involves putting high amounts of modulated RF on a power line. The Amateur Radio Relay League has the most informative page on the topic. The hazards include exceeding MPE (maximum permissable exposure), RF burns, and disrupting the HF bands of radio. This last one would also work in reverse, meaning hams, airplanes, or the military keying up their radios could take out large areas of internet service (with airplanes, potentially over several hundred miles)."

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First, and... (3, Interesting)

Zondar (32904) | more than 10 years ago | (#8020798)

Being near a hot unshielded antenna lead of sufficient power output is bad news...

Re:First, and... (5, Interesting)

grub (11606) | more than 10 years ago | (#8020875)


Being unshielded makes me wonder about the likelyhood of "sniffing" with a receiving antenna and amplifier. It's spread spectrum like the cable 'modems' but ya never know. I'm sure the NSA is ready for any potential rollout. :)

Re:First, and... (1)

Feyr (449684) | more than 10 years ago | (#8020952)

making it spread spectrum doesn't really protect you form eavesdroppers. you can still sniff it out, it just take some more expensive equipments

no bad jokes intended, but the russians did it

Re:First, and... (0)

Anonymous Coward | more than 10 years ago | (#8021029)

in soviet russia, spread spectrum sniffs YOU!

bad joke intended.

Re:First, and... (2, Insightful)

BoldAC (735721) | more than 10 years ago | (#8021066)

What the heck? I know St. Louis-based Ameren has been testing this for over a year. [wired.com]

I have seen a lot of data and reports on the interference problems which I think we all expected. However, I have not seen anything that this would be actually dangerous. Surely with the testing somebody would have noticed if people were getting zapped.

I would like to see some data before labelling this as potentially dangerous to one's health.

AC

Re:First, and... (0)

Anonymous Coward | more than 10 years ago | (#8021168)

They are not talking about people being zapped instantly so much as slowly microwaved to increase the probability of having cancer.

probable ARRL site overload (0, Offtopic)

falconfighter (722315) | more than 10 years ago | (#8020803)

ARRL, prepare to be /.'ed They probably aren't used to the /. level of bandwidth. They're nice people. Be nice to their server :)

Useless for America... (-1, Flamebait)

mphase (644838) | more than 10 years ago | (#8020805)

so I really don't care if it fails. Damn snotty American me.

3rd world?!? (5, Insightful)

prufrax (521403) | more than 10 years ago | (#8020806)

How can broadband over powerlines be a solution for the 3rd world? Surely you need most people connected to mains power first!

Re:3rd world?!? (0)

Anonymous Coward | more than 10 years ago | (#8020890)

Yeah. Many users wouldn't be able to connect their computers to the internet until they got power lines in their area.

Re:3rd world?!? (4, Insightful)

grub (11606) | more than 10 years ago | (#8020902)


Exactly.

Considering that they have yet to get power to so many of these areas, wouldn't it be wise to run fiber optic at the same time as they run new powerlines? The fiber could handle all their telecom and network traffic. Even TV, etc.

Re:3rd world?!? (2, Insightful)

77Punker (673758) | more than 10 years ago | (#8021300)

Right on! Furthermore, when these people have power, they still won't have computers. Even if they got computers, they'd have bigger problems on their mind.

Re:3rd world?!? (-1)

Anonymous Coward | more than 10 years ago | (#8020906)

I'd rather see some success with the various cheap on-site solar solutions that are being offered for the third-world.

Re:3rd world?!? (3, Informative)

AmigaAvenger (210519) | more than 10 years ago | (#8020923)

That wouldn't solve the problem, HF interference doesn't exactly stop when it hits the border of a country, it is a worldwide problem.

Re:3rd world?!? (2, Informative)

TruelyGeeked (718423) | more than 10 years ago | (#8020977)

This is exactly why the dangers of this potential connectivity option are much less hazardous than some would lead you to believe. They aren't talking about running data over every power-line in every building in Atlanta. The main areas I see this being used consist of rural areas and developing countries (when running power lines, why not run inet lines too?). These areas aren't going to have much stuff that causes/recieves interference.

Pure and unadulterated Bullshit (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8020808)

Read the subject!

Re:Pure and unadulterated Bullshit (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8020813)

suck some jew cock faggy

FUD (-1, Flamebait)

rtp (49744) | more than 10 years ago | (#8020817)

The technology works - broadband over power lines.

If there's any significant interference issues, we ought to be looking to ultra-wide-band for alternatives to some radio applications.

Re:FUD (4, Informative)

Zondar (32904) | more than 10 years ago | (#8020865)

Yeah, it works. The question is, at what cost?

Do you really know what the amateur radio community does for the public, rtp?

Re:FUD (-1, Flamebait)

Detritus (11846) | more than 10 years ago | (#8020888)

Dumping my sewage and garbage on your front lawn works fine for me too.

Re:FUD (0)

Anonymous Coward | more than 10 years ago | (#8021075)

Yeah, that pretty much seems to be what you use Slashdot for, Demetriutitus.

New radios for everybody! (2, Insightful)

mr_mischief (456295) | more than 10 years ago | (#8020914)

Yes, it's great policy to make people who buy their own equipment, pay for their own training, pay for their licenses, and must agree to use their own time and own private equipment for public service when necessary go out and pay for new training, new licenses, and new equipment just to keep the privileges they now have.

Re:New radios for everybody! (2, Insightful)

Zondar (32904) | more than 10 years ago | (#8020932)

And the rest of the world, since it's hard to talk to someone on UWB who still has old equipment...

Slashdotted... (4, Funny)

PatrickThomson (712694) | more than 10 years ago | (#8020818)

Oh great, now a slashdotting will take out all the power and aircraft in a hundred mile radius

Re:Slashdotted... (1)

ooby (729259) | more than 10 years ago | (#8020897)

It doesn't appear to be slashdotted yet.

Going both ways (5, Interesting)

Anonymous Coward | more than 10 years ago | (#8020826)

Do note that the problems of interference goes both ways: broadband over powerlines will jam HF communications (including emergency services some places). But at the same time a HF jammer or a HF over-the-horizon radar will jam broadband over powerlines.

HF being global means a jammer in the Pacific can take out broadband in Europe.

This isn't news... (5, Informative)

Jay Maynard (54798) | more than 10 years ago | (#8020827)

...well, mostly. The hazards of RF exposure are controversial at best, with widely varying opinions in the medical community and no real, controlled studies. It's pretty certain, though, that at the low HF frequencies that the BPL folks are proposing, the effects of exposures to a few watts are pretty minimal.

This doesn't mean that BPL is a good idea. As the ARRL (which stands for American Radio Relay League) correctly points out - and has been covered on Slashdot before - BPL is a disaster for HF radio communications. Government agencies are weighing in strongly against it. I doubt it'll see the light of day in widespread use in the US.

There's no real need for it in the US either (2, Interesting)

Sycraft-fu (314770) | more than 10 years ago | (#8021019)

We really don't lack for communications infastructure. Between our huge telephone and cable networks, and growing amount of fibre thereof, we are doing fine. The majority of the problem with getting broadband to end users comes from stupidity and/or anti-competitive behaviour on the part of cable and phone companies, not lack of infastructure to carry the data. Maybe in developing nations there is more benefit, but I kind of doubt it.

Lets hope someone takes a wise decision (3, Interesting)

Eric S Rayrnond (739458) | more than 10 years ago | (#8020831)

HF radio is *the* communication medium for many life-critical situations. It is the only affordable communication line for many NGOs operating in third world countries, and HF equipment is much easier to setup and more rubust than satellite equipment.

Until now, the HF spectrum has been carefully regulated to avoid harmful interference. It is just not acceptable to sacrifice it simply to get a cheaper Internet access. There are a good set of broadband technologies available which almost do not interfere with HF users.

Let's hope politicians don't wait to do anything until a true emergency happens...

Re: Lets hope someone takes a wise decision (5, Informative)

Zondar (32904) | more than 10 years ago | (#8020901)

From the article, it appears the Japanese already have decided to kill this system.

http://www.jarl.or.jp/English/4_Library/A-4-1_Ne ws /jn0208.htm

Maybe our lawmakers could have their aides read up on why?

Re: Lets hope someone takes a wise decision (0, Offtopic)

Walterk (124748) | more than 10 years ago | (#8020984)

What could be more life critical than cheap, fast Internet access?

Re: Lets hope someone takes a wise decision (1)

borjam (227564) | more than 10 years ago | (#8021345)

Its funny to see my comment to this same question "copypasted". Fortunately, the copier has been kind enough to correct my typo in the original comment... :-)

Down already? (3, Informative)

CaptainAlbert (162776) | more than 10 years ago | (#8020832)

Seems to be Slashdotted already, even though I'm seeing 0 comments @ -1...

Then again, I didn't think anyone really believed this, did they? I mean, any first-year EE student can tell you that mains cable is no good for signalling on, even at modest frequencies. Bah.

Re:Down already? (1)

CaptainAlbert (162776) | more than 10 years ago | (#8020860)

Well, I stand corrected, because I can magically see it now. Perky intarweb.

Re:Down already? (1)

Albanach (527650) | more than 10 years ago | (#8021064)

any first-year EE student can tell you that mains cable is no good for signalling on, even at modest frequencies.

So if it's no good for signalling on, why are there commercially deployed Broadband over Power Line projects in mainland Europe and Commercial trials [hydro.co.uk] in Scotland and England offering 1Mb symmetrical connections.

Neighborhood popularity of amateur radio (5, Insightful)

rharkins (307487) | more than 10 years ago | (#8020833)

Having an amateur radio antenna is like a lightning rod for neighborhood electronics problems. I've not transmitted for a couple of years now, but that has not stopped neighbors from blaming me for every glitch that occurs with their electronics. I can imagine what will happen if I key up my transmitter and disrupt every internet connection for a couple of miles....

Re:Neighborhood popularity of amateur radio (1)

Jay Maynard (54798) | more than 10 years ago | (#8020866)

I plan to put up a vertical here with no coax attached a couple of months before running a feedline out to it, just to see how my neighbors react...

Re:Neighborhood popularity of amateur radio (2, Informative)

PatMouser (1692) | more than 10 years ago | (#8021301)

Take a look at the Force-12 Sigma-5 for a nice vertical for limited space. I've got it, 145' of wire running to an AH-4, and a 3 element 6m beam (what, you mean it isn't a TV antenna?) up with no neighbor complaints.

K0OOK

Wonderful.... not (4, Interesting)

Arimus (198136) | more than 10 years ago | (#8020836)

Oh goody so now the power companies will have even more control as they blat out most LF/HF wireless within a certain distance of their transmission lines (or should that be antena lines now?)...

Not to mention won't people who choose not to receive broadband via power still be able to tap into the transmission signal and so monitor other peoples traffic easier than trying to splice into the fiber backbone (oh hang on.... wonder if the gov't might not be keen for this very reason)...

3rd world countries (0)

Anonymous Coward | more than 10 years ago | (#8020845)

What HAMs are their in Haiti? Would the downtime justify fiber optic wires throughout the country? Now in America... we have no excuse to not use fiber optic. Especially since there is so much unused in the ground.

You think that's bad... (2, Funny)

Natestradamus (527591) | more than 10 years ago | (#8020862)

I don't even want to -think- about what happens when the vacuum cleaner gets switched on!

Re:You think that's bad... (1)

compbrain (625174) | more than 10 years ago | (#8020934)

Do your laundry, vacuum your floors, and wipeout internet for your neighborhood all in one foul swoop. Sounds like bad news to me.

Re:You think that's bad... (1)

TeknoHog (164938) | more than 10 years ago | (#8021172)

I don't even want to -think- about what happens when the vacuum cleaner gets switched on!

  1. You have the equivalent of a Windows machine online.
  2. In case you're Finnish, insert a lame joke about downloading [homeunix.net] (here the verb for vacuuming is slang for downloading).
  3. Profit!

Laugh Test (5, Funny)

Detritus (11846) | more than 10 years ago | (#8020863)

How did BPL ever get past the laugh test?

"Let's put something that looks like high-power broadband RF noise on long, unshielded, untwisted power lines, suspended in the air, otherwise known as antennas."

Re:Laugh Test (2, Interesting)

moonbender (547943) | more than 10 years ago | (#8021184)

It's considered an option here in Germany, although DSL is now widely available and seemingly has basically killed demand for BPL. However take note that if I recall correctly it was considered a means to connect the "last mile" not in rural but in urban areas. Power lines suspended in the air are virtually unheard of in German cities as far as I know. The maximum length of data carrying wire was less than a few kilometres - I assume it ended at the nearest node in the electricity grid, similar to the way DSL does.

Re:Laugh Test (0)

Anonymous Coward | more than 10 years ago | (#8021364)

Yeah but its one helluva hotspot :D

Just cover yer nuts.

Aircraft ILS and power-line transmissions (3, Interesting)

CdBee (742846) | more than 10 years ago | (#8020869)

My grandfather was an air-crash investigator, and once investigated a european crash (May have been Switzerland in around 1970, apologies, I don't have any details) in which an airliner had apparently tried to land on the side of a mountain. It was proved that the accident happened due to the local electricity generating grid using high frequency modulation to carry messages over power lines. The chosen frequency was a close enough match to the Instrument Landing System on the aircraft to cause it to engage. I hope modern airliners have better ILS.....

The Instrument landing system (2, Informative)

AzrealAO (520019) | more than 10 years ago | (#8020967)

would have had to be switched on by the pilots.

This story doesn't pass the smell test, or would you have us believe that planes run the risk of their instrument landing systems just "switching on" and attempting to land the plane automatically every time they pass an airport with ILS aids?

Re:The Instrument landing system (0)

Anonymous Coward | more than 10 years ago | (#8021093)

ILS is a pilot aid. What he meant was that the ILS would lock onto the incorrect signal. RTFP.

What the hell was ILS doing on... (1)

AzrealAO (520019) | more than 10 years ago | (#8021217)

while they were navigating around a mountain, not trying to land?

His story makes no sense at all, in any capacity, and a search of crashdatabase.com finds no crash matching any of the "Facts" of his poorly remembered, almost assuredly appocryphal story more than 30 years old.

Re:What the hell was ILS doing on... (1)

CdBee (742846) | more than 10 years ago | (#8021272)

I'm relaying a story I was told by a close member of my family. I can't vouch for any of the details.. but I did say that in my post.

Re:Aircraft ILS and power-line transmissions (2, Informative)

vlm (69642) | more than 10 years ago | (#8021140)

Frequencies are wrong for ILS which runs adjacent to the VHF comm band, more or less.

Far more likely, was an IFR NDB approach where they were trying to use the NDB to avoid the mountain, unfortunately they managed to avoid the interfering power lines instead, thus hitting the mountain..

NBD freqs are in the 200 to 500 khz range which is adjacent to some of the signalling done in the sub 200 Khz range.

"Dangerous" is overstating it (5, Insightful)

robslimo (587196) | more than 10 years ago | (#8020873)

Hams are more concerned about the interference issue than the health risks, and rightly so. The potential health hazards created by modulating the power lines should be minimal, assuming the level of modulation is kept reasonably low.

The interference caused to more traditional RF communications is likely to be significant because you are, in effect, stringing miles and miles of antenae across the countryside. The best bet might be to modulate on bands that are presently home to digital communication and in coordination with those present modulation schemes such that they don't interfere with each other.

I suspect the whole issue may be moot, as I doubt that BPL will ever see a largescale rollout for other technical reasons besides these.

Here in Spain (5, Informative)

octal666 (668007) | more than 10 years ago | (#8020885)

That is in South Europe, just in case anyone doesn't know, we have broad-band over many companies, but main power-line distributor, Iberdrola, is now starting to offer this service with lower prices than other operators. I was thinking to switch to them since they offer lower prices and better service, and they have even run a test program over a few months in the city of Zaragoza and near country area with no known problems, I'm surprised to see that news here.

Re:Here in Spain (0)

hkfczrqj (671146) | more than 10 years ago | (#8021261)

Here in Chile, Endesa is performing some tests now. The results are mixed: if the powerline is underground, there is no interference noticed (this is reported by hams [www.qso.cl] and other radio operators!). However there is fear [www.qso.cl] that much interference could render the HF band useless, specially if the powerlines are exposed.

How are the powerlines run in Zaragoza? Underground? Are there any complaints by the spanish radio operators?

Cheers...

What a way to go (4, Funny)

kinnell (607819) | more than 10 years ago | (#8020887)

Imagine being fried by a stray IP packet

Re:What a way to go (1)

shaka999 (335100) | more than 10 years ago | (#8020955)

This gives a new meaning to a DOS attack.

Re:What a way to go (0)

Anonymous Coward | more than 10 years ago | (#8021057)

Now that really is a ping of death

Solution? (4, Interesting)

sameerdesai (654894) | more than 10 years ago | (#8020891)

I know most of the big cities have their power lines underground (at least mine did). The broadband company took it to their challenge to even put the broadband cables underground. I guess that could provide sufficient shield along with the shielding on the cable itself. Now the question is cost of doing this over the entire country, which I have no clue. Again I am just curious as to how will these two cable interact because it is failing my general electromagnetic knowledge.

Re:Solution? (3, Insightful)

Zondar (32904) | more than 10 years ago | (#8020946)

What about those spider-web of antennae known as house wiring?

You can't realistically shield everything in the current state of the power distribution network...

Re:Solution? (1)

sameerdesai (654894) | more than 10 years ago | (#8021105)

I would call that a bad wiring!!!

broadband over powerlines, it's just silly. (5, Funny)

Saven Marek (739395) | more than 10 years ago | (#8020905)

And quite dangerous.

I mean, really, who expects this to work [fiftythree.org]

Ham radio FUD (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8020912)

The HAM radio lobbies seem to be quite influential everywhere. I don't quite understand why, they must be part of some conspiracy of freemasons or illuminati or whatever... but I see that they are set against this PLC thingie.

I have heard enough times about how having a HAM aficionado in the same building could mean no clear TV or radio signal to you... It must suck to be on the receiving end of some interferences now.

OTOH, I feel HAM radio is something akin to smoke signals nowadays... c'mon get on IRC already you XXth century cavemen!

Re:Ham radio FUD (5, Informative)

falconfighter (722315) | more than 10 years ago | (#8020975)

The reason is that we take care of the community in case of emergencies. In most cases, if something happens, hams are on the scene within 5 mins. We can relay messages in virtually no time (provided there's no other way to communicate) and basically are just there in emergencies.

What? (5, Insightful)

Anonymous Coward | more than 10 years ago | (#8021087)

Hams are "set against this PLC thingie" because it would basically wipe out our service. The ARRL has fought encroachment onto our allocationtions for seventy-five years, and rightly so: ham radio trains young people in electronics and provides a free, emergency communications service that works even when "the grid is down." Ironically, my first exposure to IRC was on a ham TCP/IP packet network.

As far as "no clear TV or radio signal for you" goes, interference cases almost always trace back to poor shielding on consumer electronics devices, not dirty ham transmitters. If your TV can't deal with 1500 watts next door, I'm sure your local ham would be glad to put a passband on it. Which, as a result of ham radio, he knows how to do.

KB3CAX

Support (2, Funny)

savagedome (742194) | more than 10 years ago | (#8020918)

Ever see those medicine commercials where the human body is struck by lightning.
Now, a different wave of support questions.

Support Monkey: Sir, do you see lighting like things on your computer? Sir... Sir...
(To his colleague monkey) Looks like he hung up

Re:Support (2, Funny)

multipartmixed (163409) | more than 10 years ago | (#8021084)

Hey, at least now we know why the consoles in Star Trek blow up so easily.

Gene Roddenberry truly *was* a visionary.

Suggested before (2, Informative)

PhatKat (78180) | more than 10 years ago | (#8020920)

The idea of transferring data over power lines has been suggested before... but at least in the case reported in wired of Nov. 2001, it didn't work--despite what everone wanted to believe.

the article [wired.com] .

Bush Administration thinks this is dangerous... (2, Funny)

Anonymous Coward | more than 10 years ago | (#8020933)

...and is a threat to their broadband over oil pipeline plans.

Polluted sine waves (1)

AstroSurf (629842) | more than 10 years ago | (#8020936)

The print version of Nexus Magazine http://www.nexusmagazine.com/ had a story on micrwaves in the power lines. It's not pretty.

Concept only (0)

Anonymous Coward | more than 10 years ago | (#8020947)

The whole idea of broadband over power lines is an interesting science experiment and shouldn't be implemented commercially.

Will someone finally shoot this horse?

Don't use RF (5, Interesting)

Hellkitten (574820) | more than 10 years ago | (#8020954)

What some power companies here (norway) have done is to use a special kind of machine (it looks like a really clever invention) that "spins" fibre optic cable(s) around high voltage power lines. This doesn't work for buried power cables, ofcourse. This technique gives several advantages: Cheap, the cost is the cable and a helicopter, no digging, no new cable masts, no buying right of way. Security (I'd think twice before trying to mess with a cable wrapped around a high voltage line :D ). And since light won't be disturbed by the magnetic fields generated by the current there is no need to worry about power and data interfering with each other

Re:Don't use RF (0)

notbob (73229) | more than 10 years ago | (#8021052)

Now that sounds like a good solution for a change.

Go you funky norweigans.

Re:Don't use RF (1)

SETY (46845) | more than 10 years ago | (#8021076)

Do you have any links to this technology?
BTW, Faraday effect WILL change the polarization state of the light.

Re:Don't use RF (1)

JonoPlop (626887) | more than 10 years ago | (#8021101)

And since light won't be disturbed by the magnetic fields generated by the current there is no need to worry about power and data interfering with each other

Let us not forget that light, too, is an electromagnetic wave, though.

Re:Don't use RF (3, Interesting)

carndearg (696084) | more than 10 years ago | (#8021103)

And since light won't be disturbed by the magnetic fields generated by the current

I remember reading a very interesting article years ago, may have been 1980s, about a device for measuring leakage currents in metal pylons(towers) on very high voltage power transmission lines. It was a fibre optic device, you wrapped it round the base of the pylon and measured the amount of light you could transmit through it. It seems that the magenetic field generated by the leakage current affected the refractive index of the fibre, varying the amount of light that could escape, thus you could non-intrusively measure the current by measuring the amount of light you lost.

Of course, they probably used a special fibre optic material with the right properties, but I have often wondered how they get round this with the fibre-on-powerline systems. Sadly I cant find anything about it on the www.

FAQ (4, Informative)

Goody (23843) | more than 10 years ago | (#8021011)

There's isn't a biological threat from BPL, but the interference issues are very real.

Here's a BPL and Amateur Radio FAQ [qrpis.org] .

I wish (2, Insightful)

Anonymous Coward | more than 10 years ago | (#8021017)

I wish we would stop throwing all sorts of half-assed technologies at the problem. Simply dig a hole, put some fiber in it and drown people with bandwidth. Yeah, it's going to cost more and it'll take longer, but it will also LAST us longer. I am typing this on a collaboratively installed 100 MBit/s ethernet which is attached to other similar networks via a city-wide gigabit backbone. We did a lot of digging and paid thousands, but it was so worth it.

RF Hazard? (1, Informative)

fatboy (6851) | more than 10 years ago | (#8021024)

The hazards include exceeding MPE (maximum permissable exposure), RF burns, and disrupting the HF bands of radio.

Um, you just made that up didn't you? I have never seen anyone, including W1RFI (Ed Hare), state that there was any type of RF hazard from BPL. It does pose a serious interference problem for anyone using HF, but not a health risk.

Re:RF Hazard? (1)

falconfighter (722315) | more than 10 years ago | (#8021048)

Then why do I have to do exposure checks when I run 50w at my station? If you're constantly exposed to RF for days and weeks and years at a time, every time you went outside, yes, I think it would harm you. Maybe not at first, but when it gained widespread use....

Re:RF Hazard? (1)

fatboy (6851) | more than 10 years ago | (#8021214)

Then why do I have to do exposure checks when I run 50w at my station? If you're constantly exposed to RF for days and weeks and years at a time, every time you went outside, yes, I think it would harm you. Maybe not at first, but when it gained widespread use....

I suppose you have an antenna that is really low to the ground and are operating at frequencies above whole body resonance. Compare your station to one operating at say, 14Mhz with 50 Watts into a dipole at 30 feet, you can be in compliance 2 feet away from the antenna.

Re:RF Hazard? (1)

vlm (69642) | more than 10 years ago | (#8021196)

What about cheap breakers, switches, and dimmers that depend on switching during the AC zero-crossing interval? Won't the presence of even a tiny bit of superimposed HF keep the arc alive in a circuit breaker until it incinerates the device?

Also losses in the cables will be immense so both the headend and subscriber boxes will have to use huge transmit power levels, so the level might be low at the middle of the cable but the transmitters might have to be dozens to hundreds of watts (?)

Re:RF Hazard? (1)

fatboy (6851) | more than 10 years ago | (#8021389)

Also losses in the cables will be immense so both the headend and subscriber boxes will have to use huge transmit power levels, so the level might be low at the middle of the cable but the transmitters might have to be dozens to hundreds of watts (?)

Dozens to hundreds of watts at HF frequencies means little in the way of RF exsposure. Even during the first wavelength from the head end, there is not enough power to cause problems for people walking under the power lines. (IF they are about 30Ft in the air) Now, it will devistate HF communications, but it won't present a exsposure hazard.

Jury is still out on the danger. (4, Interesting)

TEB (566487) | more than 10 years ago | (#8021073)

The hazards of RF exposure are still being debated. Hazards from BPL would need years of study. That being said people are probably at more risk from intentional radiators like WiFi points. This is due to the way the body absorbs RF. The absorbtion is a function of the wavelength of the RF and the size of the human body. I don't remember the exact data but the shorter the wavelength the better the absorbtion. This does have some exceptions but I do remember a strong absorbtion around the 1Ghz range.
The interference problem is the greater of the two. Yes it will interfere with radio communications but the interference will be worse for BPL. Aircraft have the potential to cause interference over a wide area due to their altitude, but the tranmitter is relatively low power. The real problems will start when a ham operator can't talk to his buddy 20 miles away. They get tired of the interference so they kick in the linear amplifiers. Since the max leagal power for most of the bands is 1500 watts they have the potential to take out BPL in a very large area.

terrorism potential? (0, Troll)

circletimessquare (444983) | more than 10 years ago | (#8021095)

someone smarter than me might be able to figure out how to modulate rf over powerlines, whether for broadband purposes or not, to cause death and destruction in strange new ways

just by thinking this, is ashcroft going to knock on my door now?

seriously though, am i way off base or are their novel and creative ways to use power lines to do weird rf resonance things that might be analogous to that cliche of an opera star exploding a crystal glass with her voice? would it be easy?

please forgive my ignorance if i sound silly

Power company has a network here in NY (4, Informative)

IGnatius T Foobar (4328) | more than 10 years ago | (#8021121)

Here in the New York area, the power company (Con Edison) has a broadband network. You know how they did it?

They used the fact that they already own the poles, to string up their own fiber optic cable.

This, to me, is the primary indication that broadband over power lines just isn't going to happen. When even the power company doesn't believe in it, you know it's a dud.

Re:Power company has a network here in NY (1)

splateagle (557203) | more than 10 years ago | (#8021380)

or perhaps Con Edison just wanted to deploy a system now using tested technologies. Meanwhile in a more forward thinking and inventive nation (Scotland) commercial trials are underway [southern-electric.co.uk] of a system which uses the power lines themselves.

One more time folks, say it with me "the USA is not the entire world"

Re:Power company has a network here in NY (0)

Anonymous Coward | more than 10 years ago | (#8021432)

ConEd has fiber? Ok, so what? ConEd also has a BPL network - just ask the ARRL.

shovel, beer, sandwiches and tent (0)

Anonymous Coward | more than 10 years ago | (#8021170)

sounds like another "i don't want to leave
my house and get my hands dirty putting cable
in the ground, but just wanna plug a "new
device thingy(tm)" into elec. wall outlet.

burying cables is !F!U!N!

"what's the hangup gentelmen?"

ah! i see we're running outta copper and phyber!
that must be the problem!

acctually all this data over elec. grid is just
super lame.

anyway IF you should decide to go with phyber
do give me a call. i'll bring my own shovel.
you just provide the beer and the sandwiches. i
even got my own tent! ...

Are there 2 types of broadband-over-powerline? (2, Informative)

carndearg (696084) | more than 10 years ago | (#8021188)

As I understood it from the last time this was mooted here in the UK we were going to see this as a last mile solution from your local distribution transformer to your home. The substation would get its internet connection via fibre and redistribute it in much the same way as low power mains intercom and network products work, with very low range. In the UK context this would be at the 11kv-to-240v transformer which usually serves a street of houses.

Am I right in gathering that the systems described here use high power HF on powerlines to distribute over much longer distances than this?

found this picture... (1)

silicon1 (324608) | more than 10 years ago | (#8021203)

...of an RF burn from a MRI machine:
http://www.cis.rit.edu/htbooks/mri/chap- 9/images/rf-burn.jpg
doubt a powerline would be this bad, but I really am not certain.

Re:found this picture... (1)

gsperling (625206) | more than 10 years ago | (#8021264)

Your link is not working. Perhaps you could provide a new link, or the tree you followed? I'm interested in seeing this picture.......

Re:found this picture... (0)

Anonymous Coward | more than 10 years ago | (#8021391)

Try taking the space out of the link. Now you'll know better from now on.

Power grid already has fiber... (2, Informative)

Goose Bump (454208) | more than 10 years ago | (#8021218)

Here in the mid-atlantic region, AEP has most of their power grid strung with fiber alongside the power lines. I have a friend who works in a local office and he used to amaze me with the bandwith of their network. AEP uses the fiber for their company data and voice networks as well as leasing the lines out.

Judge for yourself (1)

Greymane3 (743260) | more than 10 years ago | (#8021276)

This article misstates key facts about PLC. Most importantly, it does not use high levels of RF power. It uses milliwatts of power spread over 2-30 MHz band. ARRL transmitters pose a far greater health risk (if any) when they radiate 10 to 1000 watts of power. Commercial broadcasters routinely transmit 10's to 100's of *kilo*watts and they are not considered enough of a health hazard to prevent them from operating. Let's put this one in perspective.

BPL or.... Wireless? (1)

03 Guy (638501) | more than 10 years ago | (#8021291)

Wouldn't it be a mute point if Verizon and others successfully roll out 3g and users had THAT as an option... their speeds should be 500-800kbps...

sure it's not DSL or Cable speed, but it would be far greater than POTS.

Getting good coverage would be the problem, though. Maybe it would spark (no pun intended) a revolution in home wireless 3g antennas?!

ARRL! (1)

TeknoHog (164938) | more than 10 years ago | (#8021323)

Sounds like a file sharing organization! How could they be against any kind of broadband! ;-)

That must be fun in the DR... (0)

Anonymous Coward | more than 10 years ago | (#8021329)

Seriously - I don't see this working in places like the Dominican Republic where people tap into the power mains, and the government performs rotating blackouts to nail those guys...


Personally, I think simple repeater X.25 stations set up everywhere with wireless links everywhere is still the best bet for such conditions.

LANs (1)

Psx29 (538840) | more than 10 years ago | (#8021334)

Does anyone know if the same basic principles used in transmission of broadband over powerlines are employed in those LANs you can connect to any power outlet?
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