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Utility Cuts Short BPL Trial
fatboy writes "The ARRL is reporting that Alliant Energy has called an early end to its broadband over power line (BPL) pilot project in Cedar Rapids, Iowa. The "evaluation system" went live March 30, and plans were for it to remain active until August or September. Alliant shut it down June 25. Ongoing, unresolved HF interference from the system to retired engineer Jim Spencer, W0SR, and other amateurs prompted the ARRL to file a complaint to the FCC on Spencer's behalf demanding it be shut down."
- Put up power lines - = huge aerial system
- Inject wideband RF into huge aerial system
- Interference!
In fact the whole idea of RF over power lines, though attractive at first sight, is a triumph of will over physics. A system designed to take kilovolts at around 50-60Hz, with mechanical switches all over the network and a mixture of capacitors and inductors to adjust power factor, is not a benign environment for RF. But people keep trying to do it. There have been attempts at LANs over household wiring - but wireless networking has just about killed that with a combination of speed, convenience and safety.You can adapt a car to travel on water, but the result is expensive and technically poor. In the same way, I feel broadband over AC power is a cross-model step too far.
Panurge has posted for the last time. Thanks for the positive moderations.
They already tried. They already failed for much the same reasons, except i believe it was also interfering with LW and AM radio signals.
You dont mess with the BBC's signal in the UK. The phase "Ton of bricks" does not give justice to what will happen
let's hope this is the first nail in the coffin of a truly bad idea.
How is BPL a bad idea? Aside from the problems that need to be worked out with interference with hobbists, this could be a legitimate alternative to dsl and cable. It would be wonderful if a bit of competition could make broadband a little more prevalent/affordable.
Oh my, I think Dave just turned into a bear.
The big problem with BPL, as was stated by a poster in a previous article, is the wire. Unshielded transmission line will create signals that interfere with radio service. Unshielded wire will also act like a big antenna and pick up noise, thus limiting the bandwidth of the data the line can carry. Replace the wire with something better, and well, you don't have broadband over power lines any more. You will, however, have a workable system without the interference problems.
Nice. I'm sure comms companies all over the US will jump at the chance to get the ARRL's contribution and involvement in future.
Either way, it's great to see that the FCC is standing firm to protect sad lonely guys holed up in their bunkers listening to strangers over the airwaves from the interference of sad young(er) lonely guys holed up in their bunkers looking at strangers over the ether.
Somehow the defeat is poetic justice.
Seastead this.
How is BPL a bad idea? Aside from the problems that need to be worked out with interference with hobbists, this could be a legitimate alternative to dsl and cable.
Imagine running gigabit ethernet over silver-satin telephone wire.
Now imagine applying several thousand volts to the same wires.
The problems are not just with the hobbiests, they're just the first to notice because they happen to be interested in such things.
The problem is twofold.
First of all on HF spectrum there are not only amateur radio operators: ships, aircrafts, military, private services, broadcasting stations and so on.
If there is an harmful interference to an amateur radio station it could be as well exist an harmful interference to an international airport or a coast guard station. And they can't hear an airplane or a boat distress call.
Using wires made for 50/60 power to transmit data
at high speed is a bad idea because the infrastructure was made to transmit power: the impedance is low and variable, cables aren't paired or shielded, and there is a lot of noise.
Power utilities have a right of way, so to have another competitor they have only to pull optical fibers along with power lines and put a WiFi/UMTS
base station on the poles (or a 10BaseFL/100BaseFX/1000BaseSX switch and pull fiber to the homes).
Better badwidth for users, no interferences to and from other services and appliances, and a working technology.
These hobbyists, who use a very small portion of the frequencies in question, include a large number of people who are active in public service sectors for emergencies and for the public welfare in general (for free and providing their own equipment), such as providing free phone patch services for the military in remote areas to call home. In emergencies when the local utilities go out, getting traffic into unaffected areas is very important and if that receiving area has BPL interference than life and limb could be in jeopordy.
BPL is supposed to conform to the existing rules and regulations in place stating that no service is allowed to interfere with another. Period. All these other services have to conform and just because a few people want to make money off the BPL for a few people at the expense of all others does not give them the right to use an unsound technology to do it. If they can come up with good technology that doesn't cause problems than by all means go ahead. And BTW, what are you going to do if you have a transmitter of any service located nearby that continuously knocks out your BPL link? Nothing. BPL is a Type 15 service that has no legal recourse when it is interferred with. BPL as current technology is broken and most likely cannot be cleaned up without massive expense (guess who pays) and investment in a much different type of equipment than is proposed. The power companies want to use the current equipment for BPL because it is cheap. If they have to build a different technology than it is no longer going to be cheap.
Plus what will happen should BPL go through is that the power companies will lease the grid to the existing ISPs and your fees will likely remain within a few percentage points of existing services over POTS and cable anyway. The idea is to make highspeed internet available to all, not to keep your price down.
Too lazy to create a sig...
Sending data over power cables is the first thing that strikes us when we think of broad-band. As someone involved with broad-band initiatives in india, as a veteran slashdotter and as an ex-ham, i think this needs a few pieces of missing information.
Why power lines? because they are there. More importantly, because you cannot touch any other copper lines (like ma'bell) nor lay them afresh without being billg hisself. now guess who demands this money? the very FCC!
It is often a cheaper and a simpler solution to just run a shielded cable. In India, where such zoning and municipal laws are lax, I have a 100 mbps ethernet drop into my home office. The electic poles are tapped for feeding the hubs on the way as well as providing the physical support for the cable high above the reach of straying cows, buffalos, kids on bikes and cable thieves.
The cable operators pay the electricity folks a fixed low per-pole charge. In the case of BPL, i think it is more of FCC trying to save the phone companies than creating a new last mile solution.
Why can't we lay more cable in anycase? it is a cheaper option.
The point often missed about HF is that like ozone layer, it really affects the entire world. I have a 5 watt transceiver that regularly goes around the world (www.phonestack.com/farhan) using just a 10 meter stretch of wire for an antenna. the noise that BPL will generate can easily disrupt global HF communications that form the backbone for many countries even today. Imagine the interference BPL would create by contributing megawatts of power radiating over millions of miles of wires all over the country.
blaming amateurs is really a shame. especially at slashdot. from the early open source tcp/ip (the KA9Q) to Alan cox. Amateurs have frontlined development of Internet. the very idea of personal science (as something that individuals pursue for pure satisfaction) that propels towards free and open softwares finds its foundations in amateur radio.
Amateur radio is really the only open source communication technology. Everywhere else, you still pay per use. It is also the classic peer to peer technology, it requires no 'service providers' at all just you and a couple of transistors connected to a clothline. The entire communication stack (read morse code decoder) is in your head. how's that for a setup?
The purpose of all philosophers was to impress women
It's bad idea because those "problems that need to be worked out" CAN NOT be worked out.
You can't "work out" laws of physics, and laws of physics say that large bandwidth over this kind of wires cause interference to just about everything, not just few hobbists.
You need new cables for broadband, and if you put in new cables then it's easier (=cheaper) to just go DSL route.
What if the power company were to send tinfoil hats to local ARRL members? Wouldn't that solve the problem?
Yep, it'll solve the problem. It works just the same as cutting your phone line, or cable to filter porn spam from your e-mail. It's 100% effective. The false positive rate is also 100% just as the intended communications link is now down.
The truth shall set you free!
That still doesn't make any sense. Yes, the ground wire is there for lightning protection, but not for the power distribution system. They use 3-phase Delta transmission, which only requires three wires. There is a Delta-Wye transformation done at some point to give you a neutral wire for use in buildings. There is no neutral wire in the main grid at all. Furthermore, to string critical communications fiber in a lightning cable is, well, suicide.
Perhaps this little lie was meant more for the shareholders than you.
Part of the reason for the protest has been that the power utilities have been very poor in the manner they respond to RFI complaints caused by their equipment . With that being a fact, why should hams trust that the utilities will do any better with BPL.
BPL can work, however, as it is being proposed, it is not setup to properly protect the liscensed users of the bandwidth that these systems will be radiating in. The power companies are lobbying to put in the system that requires them to do the least amount of work. Not a single one has proposed a system that would mitigate their response.
The United Power Line Council recently showed it had no real arguments against the hams cases when it responded to FCC comments by saying they were the true experts and "not a misinformed set of armchair amateurs that still use vacuum tube transmitters." Wow, name calling in a document submitted to the FCC. The simple fact is that they have not been able to refute the technical arguments. They are now trying to buy influence and namecall in order to get their way.
In any situation like this, someone invariably gets picked as a 'test case.' Jim just happened to be the one.
What he experienced in terms of RF 'noise pollution' would become all too common if BPL were to be widely deployed. The NTIA report and the ARRL's own technical committee have demonstrated this in gruesome detail.
Want some more real-life examples of the kind of crap BPL is capable of spreading? Go here.
There are plenty of existing ways to deliver broadband to homes without polluting the HF spectrum. BPL exists only to serve the pocketbooks of its equipment manufacturers, and the shareholders of power companies, at the expense of EVERYONE (not just amateur radio ops) who uses the HF spectrum. If it becomes widespread, commercial aviation, military, and the federal government's HF users will ALL be affected in short order, and it will probably get shut down anyway as a result.
Why waste any more time on it at all?
Bruce Lane, KC7GR,
Blue Feather Technologies
Reply Comments by to the Notice of Proposed Rulemaking
by Benjamin S. Gelb, KF4KJQ, a graduating senior at Thomas Jefferson High School
for Science and Technology in Alexandria, Virginia.
Before the
Federal Communications Commission
Washington, D.C. 20554
In the Matter of
Carrier Current Systems, including Broadband over
Power Line Systems
)ET Docket No. 03-104
Amendment of Part 15 regarding new requirements and measurement guidelines for A
ccess Broadband over Power Line Systems
) ET Docket No. 04-37
To: The Commission
Reply Comments to Notice of Proposed Rule Making (04-37)
Reply Comments by to the Notice of Proposed Rulemaking
by Benjamin S. Gelb
I have been a licensed Amateur Radio operator for eight years, completed multipl
e physics and electronics courses and have countless hours of hands-on experienc
e experimenting with radio and electronics equipment. I am a graduating senior a
t Thomas Jefferson High School for
Science and Technology in Alexandria, Virginia and will be attending MIT in the
fall.
The following are reply comments to various comments on the NRPM (04-37) by Curr
ent Technologies and Ambient Corporation.
Current Technologies asserts that "Current Technologies implementation of BPL is
noninterfering." I dispute Current Technologies' assertion that "Current Techn
ologies implementation of BPL is non-interfering." There seems to be a great div
ision between those who believe BPL will be a
source of harmful interference, and those who do not. I contend this division is
not a result of "misunderstandings about how BPL works" on the part of amateur
radio operators and many other individuals and organizations but rather a misund
erstanding of basic physics on the part of
both the Commission and Current Technologies.
Current Technologies states on page 14 that "Access BPL devices do not use power
lines as antennas. They use power lines to conduct data signals, not radiate th
em."
I'm sure that Current Technologies' goal is to conduct signals rather than radia
te them. Unfortunately, Current Technologies, no matter how much they wish to d
eny it, is bound by the same laws of physics as every one else. When an RF curre
nt is coupled into a conductor, that conductor will radiate. Period. This is bec
ause of the electric and magnetic fields created by the charge and current on th
e conductor.
In coaxial cable the fields are contained by a shield at ground potential. In ba
lanced line, equal and opposite fields from correctly spaced parallel conductors
mathematically cancel. Power lines have RF characteristics that are irregular a
nd variable, and do not resemble either type of feed line. Therefore, BPL system
s that couple RF to the power line will cause the power line to
radiate. Period.
This has been shown to be true in the real world. A video1 produced by the Ameri
can Radio Relay League demonstrates actual received interference in four trial a
reas, one of which is operated by Current Technologies.
Because of the great disagreement between BPL promoters and those who stand to b
e impacted by the implementations of BPL systems, it seems that the Commission o
ught to be obligated to, at the very least, conduct some sort of real world test
ing of its own to determine the radiation characteristics of power lines. To dat
e, no effort to validate the claims of either side has been made by the Commissi
on.
So far, the Commissions attitude seems to be to accept the word of BPL manufactu
rers as fact, no questions asked, despite the fact that many statements made by
BPL proponents and subsequently parroted by the Commission are embarrassingly no
nsensical to someone with even
the most rudimentary technical education (e.g. stating that the characteristics
of a power line are somewhere between a waveguide and an antenna in the NPRM). M
eanwhile, the Com
As an old Ham, and a retired Avionics technician, I see major problems with aircraft communications, as another major interference area, for aircraft that fly intercontinentally. The VHF aircraft communications frequencies are limited in range, so all aircraft that fly, for example, from the USA to Europe must have H.F. radio communications by F.A.A. regulations. Plus, I don't see all the other countries letting us out of our international treaties on radio communications, and ruining/polluting the H.F. radio bands for the rest of the world.
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.