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FCC Approves BPL Despite Interference Concerns
goosman writes "The ARRL is reporting that the FCC has approved revised Part 15 (unlicensed services) rules to specifically regulate the deployment of broadband over power line (BPL) technology. The Commission adopted a Report and Order in ET Docket 04-37 when it met in open session today. At the same time, three members of the Commission, including Chairman Michael K. Powell, specifically mentioned the concerns of Amateur Radio operators at the open meeting and expressed either assurances or hope that the new BPL rules will adequately address interference to licensed services."
I think it has been said that BPL doesn't use "twisted lines" but during hurricane Ivan half of our neighborhoods' lines were downed, and I got a chance to get an up close and personal look at the lines, and they did look twisted to me (just like any wire that is twisted up for strength). Won't this twist help keep the signal from leaking so badly?
Just another ignorant AC...
It was the wishes of a few million people that the Native Americans be displaced, but that was still wrong, just as this is too.
The tyranny of the majority is still a tyranny. Hence the reason we have a Republic, not a pure Democracy.
When I first read about using power lines to provide broadband Internet access, I was very excited, especially since I lived in an area in which there was no real competition in broadband. It seemed like a great idea. At the time I didn't realize that the unshielded power lines would interfere with Amateur Radio.
Radio Amateurs, HAMs, have played critical roles in almost every large disaster that has happened in this country. They provided emergency communications when no other communications technologies were working. Groups of HAMs regularly set up disaster drills where they perfect their ability to get information in and out of a disaster torn area. HAMs have also helped advance radio technology. The very first wireless Internet connections were set up by HAMs using 2-meter rigs connected to their computers back in the days of the first IBM PC and Apple IIe.
There might be all kinds of rules that the power companies have to follow to prevent interference with HAM radio, but my guess is that they'll just ignore them. How many amateur radio operators are going to have the fiscal resources needed to take on a big power company?
My guess is that everyone will quickly forget about this debate until a disaster strikes. Then maybe people will wonder why the communications were so poor and count the lives that were lost because of it.
If the power companies are going to disrupt the ability of HAM radio operators to provide communications during disasters, they should bear the cost of setting up alternative communication networks that can supply the needed communications. It's a cost of doing business.
Another question springs to mind, why this particular frequency spectrum, is it dictated by the application, or was this spectrum selected because there was they figured that amateur radio operators couldn't organize real opposition to it?
-All that is gold does not glitter - Tolkien
www.ra
Sure, and the rest of the time?
Look, ham gear is expensive, and people primarily use it to communicate in times of non-emergency for fun. You aren't going to find too many people who happily purchase expensive radio equipment, study and pass a license exam, then wait for a power outage so they can use their equipment.
Frankly the people who already purchased thousands of dollars of equipment and passed the required exams only to be fucked over by the FCC (suprise, we decided we don't care if your stuff works anymore) have a right to be royally pissed over this.
You want a last mile solution, look to WI-MAX, BPL is a failure.
Finkployd
Parent poster is correct, and well explained. Here's another way to look at the twisted-pair concept.
Any electrical circuit forms a loop; you can trace the current going out from the power source, through the load, and back to the other side of the power source.
For an electric power transmission line, this "loop" is the wires on the left and right sides of the power-line crossbar (OK, not all lines look like that, but the principle is the same). You can trace an imaginary line down one side of the power line and back on the other, enclosing a loop 12 feet wide and many miles long, with enormous area. This is one reason power lines are a bad idea for carrying RF signals; they make a GREAT antenna.
For radio interference, the area enclosed by this loop is an important factor; reduce the loop area, and you reduce the radiated interference. The DIRECTION of the current in the loop also counts; a clockwise loop radiates with a phase opposite that of a counterclockwise loop and can cancel it out if the two are right next to one another.
Now imagine twisting the two wires around each other; you get many very tiny loops with alternating CW/CCW directions of current flow in the loop; their net radiating effects cancel out.
Interesting note: Cross-country power lines ARE in fact twisted pairs, to prevent another interference type. At every Nth tower, you'll see the lines cross over so the left-hand line goes to the right. This results in loops of a half-mile length or so; useless for shielding from RF, but VERY important for protecting the grid from geomagnetic storms, where the Earth's magnetic field is pushed around by solar wind. Making the net loop area zero prevents the transmission line from acting as a giant DC generator and blowing out the switchgear, causing major blackouts (this happened in Canada in the 1970s, IIRC).
"My strength is as the strength of ten men, for I am wired to the eyeballs on espresso."
It won't work that way. If BPL interferes with ham radio, the number of operators will decrease below the crticical mass necessary to provide emergency communications, worldwide.
Here's why:
BPL produces interference across the entire spectrum of "high frequency" (3-30Mhz) radio, and a little above and below in fact. The HF frequencies have special properties (on this planet, at least) of being reflected around the world by the ionosphere. A tiny sliver of these frequencies are used by amateur radio operators, but there are litterally thousands of other kinds of licensees worldwide.
BPL power lines radiate this interference, and when the ionosphere is highly reflective, the interference will be sent around the world. Since the FCC denied the request to have the BPL systems transmit identification, there won't be any way for anyone to identify which BPL installation is causig interference, since it might be halfway around the country, or halfway around the world.
There are BPL systems that don't use HF radio waves, but in all the rush to "Step 3: Profit" these technical issues have been ignored, and the comlpanies with the best lobbiests have won.
I'm a ham radio operator and I can assure you that we've got far more specturm than we need or use, and this BPL stuff has great potential for rural areas where even wimax isn't going to be a viable option.
.04 cents per minute for a 128K line. T1 lines are $800-$1,200 a month - if you can get them.
And what level license do you hold? Not that it makes that much a difference, a HAM is a HAM is a HAM, but if your name is any indication, you are a technician licensee, and probably have little experience using HF bands in any case. I could be wrong, but since you fail to provide a call, I can do little more than assume that you have limited if no HF experience. And to keep things fair, my call is W4KDH, and I hold a General class license.
BPL is a really the only solution for some areas, even in this day of DSL/Cable/Wimax/3G and whatever.
NO it is not. WiMax, and in some cases even Satellite are better solutions, cheaper to implement and ultimately cheaper to maintain. Not to mention the direct benefit of no incidental RF radiation from miles and miles of antenna(power lines).
To give you folks a bit of perspective, I live 1.5 hours away from New York and Philadelphia, in Pennsylvania, a place called Bucks County, up in the north end. It's not exactly "rural" but it's still a place where people come to get out to "the country".
And again, to be fair, I live in a little place called Bear Creek, NC, in Chatham county which IS a rural area, not just a "Could be considered rural for this excercise" area. I commute an hour to work and an hour home each day due to the distance between my house and my office.
DSL service has only been offered in this area since April 2004. Cable internet access is still NOT an option and won't be anytime soon. Modem connections in many areas are - at best - 56K X2, with typical connections much slower. ISDN is charged by the minute - at
DSL service is NOT offered here. Sprint does not care for the expense of setting it up. I get dialup, and 56K X2 is a standard, not a connection speed. Typically, even in the best of circumstances, a "56K" connection will get you 52K realized speeds... I typically get 28.8 max. ISDN is not an option, as again, sprint deems it too expensive to set up the existing infrastructure for ISDN. And you can get T-1. Its just a matter of cost. Any provider will gladly provide you a T1, no matter where you are, so long as you make it worth their while to run the lines, etc.
There's a guy running an point-to-point wireless ISP operation called "Airisen" here, but it does not work where there's too many trees (like my house).
Then the reasonable solution would be to put an antenna higher than the trees. As a Ham, you should at least have SOME grasp of the basics of RF principles, and especially the idea of Line of Sight. You dont think that WiMax or 3G would be any different do you?
What matters most about BPL is that it rides on existing infrastructure - no new towers, no new wires, no digging, no aiming, no clearing trees to get line of sight.
Here you mention line of sight, but seem to overlook that WRT the aforementioned PTP wireless provider. What the problem with BPL is is that that existing infrastructure is ancient, by most standards, unshielded, and NOT MADE to carry signals at the frequencies needed for PLC. Think about it... the areas that proponents argue will be best served are the EXACT areas that those power companies have yet to actually test in.
Of course BPL works in major metropolitan areas... but no real studies have been done in the US, that I am aware of at least, involving a BPL rollout to a truely rural area (meaning an area where there is VERY limited infrastructure to begin with). Hell, my power company cant even keep the power on when we have someting like a simple rain, how can I possibly expect them to provide adequate broadband? And the same goes for most similar areas
"Our funds have never taken part in toxic or death spiral convertible financings of any sort" -BayStar's managing partne
Its a hobby until the area you are in is devastated and all other communication channels are down.