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Hams Complain about Powerline Broadband
dwm writes "Think
broadband over power lines (BPL) would be wonderful? There might be some collateral damage. The American Radio Relay League (your friendly neighborhood ham radio operators) have documented dramatic HF radio interference in areas where BPL is being tested (Check out the video of actual interference)."
...Something tells me this site is gunna go down, so here's the text of the article:
NEWINGTON, CT, Aug 6, 2003--ARRL President Jim Haynie, W5JBP, says Broadband over Power Line (BPL)--if widely deployed--would represent "spectrum pollution" on a level that is "difficult to imagine." Haynie reacted after seeing videotape and early data from recent ARRL field studies in four states where BPL is undergoing testing.
"BPL is the most crucial issue facing Amateur Radio and the one that has the most devastating potential," Haynie said. In terms of interference potential on HF and low-VHF frequencies, "nothing is on the same scale as BPL."
A form of power line carrier (PLC) technology, BPL would use existing low and medium-voltage power lines to deliver broadband services to homes and businesses. Because it uses frequencies between 2 and 80 MHz, BPL could affect HF and low-VHF amateur allocations wherever it's deployed. BPL proponents--primarily electric power utilities--already are testing BPL systems in several markets, and one reportedly is already offering the service. FCC rules already allow BPL, although industry proponents want the FCC to relax radiation limits. It's feared such a change could exacerbate BPL's interference potential.
At the West Gulf Division Convention (Austin Summerfest 2003) August 1-2 in Austin, Texas, Haynie previewed a short video (see below) that covers highlights of a recent field tour by ARRL Lab Manager Ed Hare, W1RFI. The video, which will complement technical data ARRL is gathering and compiling, turned out to be a real eye-opener for many in the audience.
Walt Dubose, K5YFW--assistant chairman of the ARRL High Speed Multimedia (HSMM) Working Group--said it was about what he'd expected. "But for most attending--maybe 60 percent--it was much worse than they had imagined, and for some it was a real shocker," he reported. Dubose said a few of those viewing the video simply couldn't believe that BPL actually was causing the high noise level.
In late July, Hare traveled some 1350 miles to visit BPL trial communities in Maryland, Virginia, Pennsylvania and New York to take measurements over significant parts of the HF spectrum. He also took initial readings at low-VHF frequencies. Driving a specially equipped vehicle loaded with radio gear and measurement devices, Hare said he didn't need to look long or track down "a few hot spots" to find BPL interference. "The signals were all over," he said.
"The interference found ranged from moderate to extremely strong," Hare said. The video shows the S meter of an HF transceiver holding steady in excess of S9 as the speaker emits a crackling din, which one observer described as sounding like a Geiger counter. Only the very strongest amateur signals broke through on 20 and 15 meters. Hare noted that the field strengths of the various systems all were within FCC Part 15 limits for power line carrier (PLC) devices.
At a couple of points, the video shows noise continuing nearly unabated on 15 and 20 meters as the car moves down long streets lined with overhead wiring. Hare said the signal propagated for at least a couple of miles down one road.
"Signals would have been much stronger using a gain antenna," he observed. Hare's vehicle carried a roof-mounted, horizontally polarized Buddi-Pole antenna--a loaded dipole.
Each BPL system exhibited a unique sound depending upon the modulation scheme it used, and Hare said he was able to distinguish three types during his recent tour. While in most cases, the signal sounded like static or pulse noise, in one city, it resembled sort of interference a computer monitor or similar device might generate, with warbling "birdies" blanketing the bands at closely spaced intervals. "Naturally, overhead wiring was the worst," Hare said. BPL signals continued to be audible in neighborhoods with underground electrical utility wiring, although it was somewhat attenuated.
The ARRL already has filed a 120-page package of text and technical exhibits
I can see that video getting hammered.
I'm grabbing a copy here
Get your own free personal location tracker
It can go around the world without the need of a network. That is all.
Occam's razor is the blind faith in the natural selection of least resistance and in universal oversimplification. -- EF
The movie site is pretty slow, so I mirrored it: BPL_Trial-small.mpg
They're not "hooked up" [think terminated], so there's lots of spare wire serving as an antenna and corrosion serving as a discriminator -- no wonder you're getting "interference" -- you have a simple radio reciever. Put a small cap across the speaker terminals and your problem goes bye-bye.
"You might as well get your son a ticket to hell as give him a five string banjo." -unknown minister
Yes. It is a distributed network of independent nodes, most of which have generators and battery backups, whose primary reason for existing is for emergency communications. In case of massive disruption of power and other transmissions ... they can keep broadcasting. It's low-tech, cheap, and easy. Can even be mobile. And in the intervals between emergencies, you can chat.
After the big Mexico City earthquake, all the microwave towers had to be realigned, the phones were out until lines and power to switching equipment could be restored, and none of the TV stations could reach their satellites - one TV building collapsed. For the critical first few hours, the hams in Mexico City (civilian, military and diplomatic nodes) were the sole source of contact between the city and the rest of the world ... much of it through New Zealand hams who then relayed the information to North America because of an odd bounce in the transmissions.
After things settled down a bit, I spent hours at a local tech college's ham setup with other bilingual persons, recieving and transcribing "we're OK" messages, while other students relayed the messages to the closest ham station they could reach that might be able to get the message through. On the Mexican end, mobile ham units were relaying messages, neighborhood by neighborhood. (most of those neighborhoods don't have running water, let alone cable for boradband).
I realize you are trolling....
But I'll bite. Recently here in NE Ohio, we were hit by some pretty bad storms that caused some pretty destructive flash flooding. Hams reporting weather conditions and flood reports over the SKYWARN system were able to get realtime info to both the national weather service and to the local Red Cross branch so that they could get shelters set up in trouble areas before they were needed. In particular, an apartment complex had two of their buildings cut off when the little 12" stream that ran in front of their building rose to 12 feet. This also knocked out power to that area, so we had roughly 100+ people isolated (the only way out was a good 40 min hike though some rough terrain even if it hadn't been pouring down rain for 8 hours already) on the other side of a now major river. Two ham's (sorry guys, forget your calls) hopped in a 4WD vehicle and went there and did an onsite assesment even before the already overtaxed police showed up on site. That is what ham radio is really set up for. The band allocation that we get to play with is meant for emergency communications. Sure, we use it for rag chews mostly, but when the crap hits the fan, I'm glad I have a 2M HT that can get me communications when I need it. The major trouble with the BPL thing is that it already creates interference on the bands, and they lobbiests want to increase the wattage they push, which will worsen the situation exponentially.
And besides, what good will a cell phone do if your towers go down like they did when the WTC fell? Ham radio had comms flowing in and out of ground zero in under 3 hours then.
Ham radio still fills a very vital role in todays world when a disaster strikes.
73 KC8SNS
Actually, Ham radio operators, being licensed do NOT have to accept interference! That is the diference between a "Part 15" device and a Part 97 device.
Your 802.11 device has to accept interference, part 97 (Ham radio) or any other licensed service does not
-- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
I'm not a radio geek, or lawyer, but, doesn't every device that has an FCC label on it basically say that you have to accept any interference that occurs? Therefore, if it bothered the 802.11 spectrum, we'd be irritated about it, and probably contact someone to get it changed. But, until things changed, we'd have to deal with it, either by filtering the noise, changing frequencies, etc.
You can't filter this stuff. It's absolutely rock-crushing interference. The problem is that the overhead electrical wiring is a really efficient antenna.
The other thing is, that Amateur Radio is a licensed service, which give it certain privileges, one of those being that you aren't allowed to interfere with it. You're thinking of unlicensed devices, like wireless phones, that aren't protected this way.
Yet another thing: BPL radiates over a HUGE bandwidth. The BPL companies want to use 2 to 80 MHz. That would wipe out the entire HF band, which hams and others use to communicate long distance. It also includes 6 meter VHF (50-54 MHz). In contrast the entire HF allocation to hams is 3.36 Mhz total. Include 6m, and it's 7.36. BPL is an enormous bandwidth hog.
This implementation of BPL would be disastrous for ham radio and anyone else using HF frequencies, like shortwave broadcasters, coast guard, government, marine, and so on.
The idea that they could obliterate 78 MHz of spectrum should be of concern to everyone, not just hams.
Either way, the ball is in the court of the HAM operators. Get together and start writing letters, making phone calls, etc.
We are. BTW, ham is not an acronym.
When the Internet and your cell phone go down the only thing left is Ham Radio. The power companys dream of providing internet access is going to do nothing but DEVISTATE the HF bands with RF pollution. Hams are not the only ones using the HF bands, the military, broadcasters and others have alot to be concernd about. Not to mention that you WILL be able to sniff packets since a great deal of the energy WILL radiate (how is the DMCA going to be enforced? ban all radios??). Power lines were built to one thing and one thing only, deliver power not deliver broad band internet services. Ham radio is still very much alive and kicking, I get on HF all the time and there is too much RF pollution there already (consumer electronics e.g. TVs, DSL modems, hubs, switches, computers etc).
"I bow to no man" - Riddick
The same place they found them after 9/11 where ham radio was the only reliable mode of comms around ground zero for a couple of days. You know who told the disaster workers WHO to contact to start getting phones setup? The Hams on site, who had contacts with the right folks
You live in, let's sa the LA area (you mention earthquakes). No a search on LA and CERT. The hams TRAIN to work with the police and fire departments in case of disaster
Look up ARES - The Amateur Radio Emergency Service
Look up the fact that ARES works closely with the Red Cross, the Dept of Homeland Security, FEMA, LOTS of fire departments, wilderness rescue teams and the like
Look up RACES - Look up what happens if the Government declares a Radio Communications Emergency (and think about what happens to your 802.11 links - say "Bye-bye")
-- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
Packet radio is extremely routable. TCP/IP is one way we do it, but actually is not the most common method.
As another poster pointed out, amateur radio operators mainly use AX.25. Both TCP/IP and AX.25 are X.25 derivatines. AX.25 identifiers are Amateur Radio callsigns with numeric suffixes (such as "N0CALL-10"). AX.25 routing is done by broadcasting while gradually incrementing your TTL until someone hears them for you (if they aren't your immediate neighbor), or manually entered information (either as a route table or "Connect to SOME1 via SOME2, SOME3, SOME4").
There are also a few other ways (such as NETROM and ROSE) amateur radio operators can route information digitally. While it would be a stretch, NETROM could be considered our equivalent of BGP router advertising and periodic route annoucements. ROSE is a polled system similar to Token Ring.
We also have our share of propritary speedup techniques (such as KA-NODE from Kantronics) and experiemental protocols as well.
That's really naive. Why do we still rely on cars? They're over 100 years old; haven't we moved to something more modern?
To suggest that ham radio hasn't evolved is completely ignorant. Modern ham radios sport LCDs, top-quality DSP filters to pull out signals you might not otherwise here, advanced speech compression, etc. Modern repeaters are Internet-linked; a local repeater might be linked with one in a foreign country over the Internet. It's hardly the radio Marconi knew.
Futhermore, hams are constantly coming up with new ideas. 'Back in the day,' it was a ham who invented cordless phones. (Which eventually evolved into cell phones.) Hams are constantly innovating; while some hams love nothing more than Morse code on an 'antique' radio, quite a few are also pioneering new technologies -- PSK31, for example, a remarkable digital technology usable on the HF (worldwide) bands, that uses very little bandwidth and is able to work well even with heavy interference.
Yet another factor you overlook is the role hams play in emergency communications. A TON of hams are actively involved in emergency communications. I'm hundreds of miles from New York City; on September 12th, 2001, several local hams flew out to NYC to help with emergency communications. In a testament to how many hams help, they were turned away due to the fact that they already had too many volunteers providing emergency communications.
I have a cell phone and a high-speed Internet connection. But what happens when there's an Earthquake, and the local phone lines (which the cell towers are connected to) and Internet lines are taken down? Hams have a history -- that lives on -- of providing emergency communications.
________________________________________________
suwain_2
The bottom line is that BPL's harmful effects ARE NOT limited to ham frequencies. There's a bunch of other services, both commercial and government, using HF from 2-30MHz.
Just as a few examples: Aeronautical HF, NOAA RadioFAX over HF, NOAA storm warnings broadcast by SITOR over HF, Federal and Marine HF frequencies... The list goes on forever.
So, it really isn't just hams that are going to be suffering. It's EVERYONE that uses the HF spectrum, including the U.S. Government!
How long do you think said government is going to let BPL exist in its current form once critical military or Justice Department installations start noticing the very same interference that'll be driving us hams nuts?
Bruce Lane, KC7GR,
Blue Feather Technologies
Check this out..
There's a link there for the PDF of the spectrum allocation. Pretty much "DC to Daylight". The piece that BPL is going to destroy covers a lot of Ham allocations. But it also covers things like:
Maritime Mobile
Aeronautical Mobile
Space Research
Standard Time Signals
Shortwave Broadcast
Radio Astronomy
Land Mobile
Fixed-station
The amateur service is a very small part of the spectrum below 30 Mhz. A lot of it is used for things like trans-oceanic flights, military and civilian mobile services, and the like.
I'm of two minds whether this will pass or not. Michael Powell, the FCC chair, hasn't made a good decision since he got into office, so I'm thinking this will go through because he's got the power companies all giving him blow jobs under the table. On the other hand, the FAA, NTIA, the military, and the shortwave broadcasters may get through to the FCC that they can't allow this, and maybe somebody will get that lamebrain Powell to do something right.
Vacuum tubes are immune to EMP and there are still a lot of HAMS out there with tube radios. The military radios for critical comms will be hardened against EMP. They've had folks working on survivable comms since the 50's.
That said, RFI problems like you described are usually NOT the fault of Amateur Radio operators. More specifically:
1. Many times the source of interference is someone operating illegally. Illegal CB operation (I.E. big huge amplifiers - which are against FCC rules, etc. etc.) is probably the biggest cause. Believe me, most Ham radio operators would love to take these people out back and teach them about respect for the rules.
2. Even if the source of the interference is an Amateur radio operator, many times the problem is tracked down to a low-quality piece of consumer equipment at the person being interfered with's end. As long as the Ham radio operator is operating within the rules, the owner of the equipment is responsible to fix the issue - as it is their equipment with the technical problem.
3. If it is in fact the amateur radio operator's problem, it is their duty to fix it. The FCC can and does pull licenses for this type of stuff.
If you are having problems along this line, contact your local Ham Radio Club a call. In most cases, they have a vested interest in finding the source of the problem and helping fix it. You can see clubs in your area by going to The club search page on the ARRL site.
Remember that Ham radio operators provide a valuable service when the crap hits the fan. Most Amateur radio operators are actually skilled in what they do and take great pains to insure they don't cause unwanted interference, as interference only hurts the Ham radio community.
Keep that in mind next time you're flying in from europe on approach to Kennedy airport.
All the communications that planes use all the way across the ocean is shortwave. Aeronautical mobile service. But this is only a few thousand people a day, no big deal, let 'em miss the airport?
Maybe next time your fishing boat is out in the atlantic and you need to call the coast guard. Maritime mobile service. Wow, this might only be a dozen people a year, let 'em drown.
Your "proportion to number of users effected" argument doesn't look so good now does it?
Every time there's an earthquake or a hurricane in the western hemisphere, I get a little email from the FCC via the ARRL telling me I can't use a specific set of frequencies because they're being used for emergency health and welfare traffic. Usually this is the non-urgent stuff, like "yeah, mom, me and the kids got through the earthquake OK". But that's only a few thousand folks a year. Let mom worry.
These are things that happen. Real people who use those frequencies in ways that make their lives better. And you are advocating interfering with all of that so you can get Internet access into your house faster and cheaper. Your "nature of use" argument begins to wear here. Seriously, given the choice between more effective air-sea rescue and cheaper porn, you're choosing the porn. Unfortunately, I think the FCC's on your side. I don't think Congress is though, they've already overruled that dickmaster once.
Admittedly, this is low power interference, but on those frequencies, it doesn't take much to send signals globally. Seriously, you can send signals with fractions of a watt in the right conditions and get good readable copy on the other side of the world. This interference level would pretty much devastate those frequencies worldwide.
"It's more of a hobby than a necessity"
As a strike team leader for a mountain search and rescue team, I'll tell you that without HAM radio, our job would be just plain impossible in many situations. There simply is no other option currently in existence. HAM radio is not only a hobby, but in my line of work it's a critical life-support resource, more so than any other technology we use (except maybe a flashlight). Tell the thousands of people whose lives have been saved through S&R or any of the other emergency situations that depend on HAM capabilities that it's not really a necessity.
KD5SMV
I have a girlfriend whose name doesn't end in
I have to second this. On a class camping trip a few years back we were at a hike-in campground along the coast in a remote part of California (yes, there are still some remote parts of California). One morning while boiling water for some coffee one of the guys on the trip accidentally overturned the pot, drenching himself with boiling water. Needles to say, he received some extremely bad burns from this. We were out of cell range, no phones within 15-20 miles, and no vehicles with us. The scope of the burns was way beyond anything we could treat with the first aid equipment we had on hand. Fortunately, one of the people on the trip was an amateur HAM radio operator and had brought his portable equipment along. Unable to contact anyone nearby, he was able to contact an operator in Hawaii, who then called the police and rescue people in our vicinity, who were then able to send a truck to pick him up in just over an hour. The HAM radio probably saved this guy's life - though yes, if we had had a satellite phone along it might have done the trick (but then it might not have - after using GPS, which tends to be extremely fickle in wooded areas, I'm not at all certain that it would have worked anyway). HAM provides a long-range method of communications that we really don't have a higher-tech replacement for at this point.
BPL should never be approved for three, sinple reasons; 1. Injecting high frequency RF onto the power lines at levels higher than the limits specified in 1989 WILL cause interference across the entire HF bands (actualy lower levels will do that). This is illegal according to FCC Part 15. Any device doing this can and will be shut down. 2. An entirely legal amateur transmitter, say a beacon transmitting 100 watts at 28.2MHz, in a common suburban backyard will render the local BPL system useless; and according to Part 15 the BPL system MUST accept this situation. 3. It is entirely unnecessary for the utilities to use the 2 to 80 MHz band for this purpose. The FCC has set aside 435MHz at 5GHZ for the Unlicensed National Information Infrastructure. This is more than 5 TIMES the bandwidth BPL could ever hope to use in HF. Systems using U-NII can be deployed TODAY (google Motorola Canopy); are already being used for broadband internet access in several communities and require no further action from the FCC. All the utilities have to do is hang U-NII nodes on the power poles at 2 to 10 mile intervals, depending on local geography. All that remains is to convince the powers that be of the obvious.
give ya a real good example of this... this past winter most of North Carolina was covered in snow or several inches of hard packed ice. Millions of people were without power and heat for as much as 3 weeks or so (we had no power at my house for 17 days).
In fact, the problems with the ice were so bad that none of the localities around had comms either. All their fancy trunked systems failed because of towers coming down, repeaters losing power and running their backups down, etc etc.
The local ARES groups activated and provided what ended up being the ONLY form of communication for at least a few days until power was slowly restored. At one point in Chapel Hill, NC, ARES members were riding around in fire trucks and police vehicles because the Cops, firefighters and Paramedics couldnt use their own radios due to outages).
I realize that a lot of what is said here is due to trolling, but some of the comments I have read are of just plain ignorance. And to answer something else, BPL does not just affect Ham frequencies... it will basically overload any reciever tuning in a freq in the HF spectrum, from 1.5MHz allthe way to 30MHz and maybe beyond. and a LOT more people than just Hams use those frequencies.
"Our funds have never taken part in toxic or death spiral convertible financings of any sort" -BayStar's managing partne
Then there is possible international issues as the ionosphere doesn't obey any kinds of national borders when propagating signals. What if a US BPL installation interferes with radio communication in an emergency in China?
Now on to your question. All kinds of overhead transmission wires can and will act as long-wire antennas and will spread these signals around. Underground cables could be less radiating, depending on what configuration they are. Thus, I would expect a 3-core cable which is three conductors twisted like a rope to contain the signals better than three individual one-core cables laid side by side. However, once these cables emerge and connect to the wiring in your house, all bets are off. I would expect the house wiring to be the biggest radiator in suburban areas where the grid is underground.
Note that "long" in this context means longer than the wavelength of the signals. For a wideband signal like BPL, the shortest wavelengths are on the order of 2 meters, (7 ft)so any piece of wire longer than about 1/4 of this can radiate some of this signal. The longer the wire, the better the radiator and the more signal is emitted and interferes. The low frequency end of the BPL spectrum has wavelengths on the order of 300 meters or 1000 feet, so even a little neighborhood-sized power spur line could radiate a lot.
Considering that the power distribution network is designed for 50 Hz or 60 Hz and most components were either designed to block high frequencies or never had any specs for these high frequencies, there could be a lot of rework needed.
Just look at a commonly seen energy meter for example; an electromechanical meter of the kind counting your consumed kilowatt-hours. This is basically a big series inductor, which does a good job of blocking these high frequency signals. So every house may need some kind of RF meter bypass or at least the old electromechanical meters may need to be replaced. Everywhere.
Stringing fibers along the power-line rights of way would be a much better way of distributing these data signals. It might even be less expensive than trying to pass high frequency signals through devices handling high voltages. Some kind of bridge for the "last mile" appears to be necessary anyways.
SIGBUS @ NO-07.308
Police hand held radios have a short range, 2 - 5 miles in most cases (Line of site can increase range to 20 miles but you can't have buildings or mountains in the way). The police cars have a 3 - 7 mile range (again further with true line of site.).
Obama = Socialism.
Broadband PowerLine (BPL) is an access technology. It is somewhat experimental and is being used to connect a service provider, like a Telco CO that is several miles from your home or business, to your home to provide broadband access. This technology needs a good deal of power to send signals over the Medium Voltage (~16 kV - think "finger of God") lines over great distances. This is the technology that the HAMers are upset about. This is also the technology that the FCC is looking at.
HomePlug Powerline technology is a home networking technology used to distribute the signal from your home gateway or music server to other devices or PC's in your home. HomePlug uses OFDM, a technology that puts a comb of carriers across the spectrum. With a comb we can then turn off and notch out the HAM frequencies. HomePlug goes from 4-21 MHz and has deep notches to prevent interference with the HAM bands in that space. A large number of FCC and CE approved HomePlug devices are available in the market (look for the NETGEAR Wall Bridges at Circuit City or the Devolo devices in Europe).
Just wanted to speak up because there's been a lot of confusion here. Intellon or HomePlug can put a whitepaper on this on their to-do list.
thanks,
James Mentz
Senior Applications Engineer, Intellon Corporation