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Mixed Conclusions About Powerline Networking vs. Ham Radio
Barence writes "Since writing about the success he's had with powerline networking, a number of readers emailed PC Pro's Paul Ockendon to castigate him for recommending these products, such as HomePlug. They were all amateur radio enthusiasts, claiming the products affect their hobby in much the same way that urban lighting affects amateur astronomers, but rather than causing light pollution they claim powerline networking causes radio pollution in the HF band (otherwise known as shortwave). Paul's follow-up feature, 'Does powerline networking nuke radio hams?' documents his investigation into these claims, which found evidence to support both sides of an intriguing debate."
It's a volunteer emergency communications organisation.
Do not mock my vision of impractical footwear
It's not a debate. Doing this turns those power lines into big antennas. You can't debate the laws of physics.
The world's burning. Moped Jesus spotted on I50. Details at 11.
The other is within-home networking like Homeplug. ARRL dealt with early interference issues and has not reported any recent ones as far as I'm aware. But the very earliest models allowed us to hear your phone call on shortwave! Fortunately, people who owned those were found and warned, for the most part.
Bruce
Bruce Perens.
Props to the egghead who called me after Katrina with a message from my sister saying she was okay.
I prefer my hams honey glazed and baked rather than microwaved anyway.
The sun is the same in a relative way, but you are shorter of breath and one day closer to death
"keeping the HF bands clear for low signal communication is a bit like keeping the rail tracks clear of fast express trains so that nostalgists can run steam trains over them."
The author's analogy belies the fatal flaw in his though process: HF communications may be older and slower than the internet, but the internet is highly unreliable and fails when communications are most critical. HF always works. HF is the ONLY completely reliable means of long-distance communication that humans have. To destroy mankind's sole means of completely reliable communication in favor of a system which fails when needed most is simply foolish. This isn't about amateur radio. It's merely incidental that most HF communications these days are by hams, and that hams handle disaster comms when the networks go down. These communications could be handled by any group of people, and the result would be the same: without a reliable HF infrastructure, humans screw themselves doubly when nature screws us.
I am a geek attorney, but not your geek attorney unless you've already retained me. This is not legal advice.
Power lines were never meant to carry RF energy. When they are, they radiate. Cable TV doesn't radiate. It doesn't radiate because it uses a proper transmission medium (Coax). If the power line folks want to distribute DATA, they should string the poles with fiber optic. Better yet, we the people should string it, and sell access to the content providers.. ala municipal fiber networks. They can work folks!
-=[ place
Wake up. BPL is a crappy technology. It guarantees improper radiation because the power lines aren't shielded at the physical layer. Kill BPL now and demand what we all want: Fiber Optic.
-=[ place
Frequency planning is an area you would need to study further before you could make sensible statements about it. Sorry, and good luck if you do decide to look into it.
Bruce Perens.
Funny, for those of us who are old, ham radio was the entry point into technology. Are you aware that there was a world before computers ? Indeed, my first real job had a realtime voice recognition system which could convert to text with few errors. You went to lunch and an hour later, when you returned (no calls during lunch..no cell phones) your letter was typed and ready for signature. We called it a secretary who could take shorthand. In this era, technology was made up of discrete components, instead of "all in one chips". Some of us wondered what those components did. We learned that they all had a job and you could easily figure it out. Better yet, people often tossed items full of these components away. We called those "dead TV's" and they were full of FREE components, which re-jiggered, would allow you to talk to Europe with a wire in the backyard. Back when the per minute cost of an international phone call was more than the hourly wage, this was big stuff. OK, today hams use four or five digital modes on HF, using little power and less bandwidth. Ham radios are smaller than a deck of cards. A 12 volt power source and small HF rig will fit in a small tool box, and can work the world on a 135 foot bit of wire. As much as I love technology, I was there on 9-11 and the entire cell net in lower manhattan just crashed. Period. The internet is tissue paper-and the current web of communications is not very hard or resilient. The old guy cranking 1500 watts in the basement with tubes is an old stereotype, and except for a few guys "keeping the AM flame alive" on 3885 mhz, gone. The knowledge you obtain hamming does translate to computers-take it apart, try to make it work, modify it. I wonder if the TFA author can discuss frequency hopping spread spectrum digital communicators....er, cell phones.
There are other services in the HF band between 1.8 MHz and 50 MHz than just Ham operators and shortwave radio stations.
The spectrum is also used for aviation, particularly when commercial aircraft are over the ocean and out of line-of-sight to a shore station. Most ships at sea use HF radio for communications from ship to ship and for ship to shore communications. The military still uses HF communications for a great many systems, including the broadcast of EAM (emergency action messages).
Someone will say "so what, they are way up in the air or in the middle of the ocean" but they fail to realize that the shore based stations are subject to interference while trying to receive signals from aircraft and ships.
There are still radio navigation systems that operate in the HF bands, weather bouys in the ocean sending back data by HF and many other overlooked systems of lesser renown.
Having spent a significant amount of my professional life hunting down interference sources to communications systems I can say it is NOT a good idea to put a thousand low powerline network extenders across a city. There WILL be harmonic interference, intermodulation and an overall decrease in performance. Look at how badly screwed up the 802.11 a/b/g/n, Bluetooth and ZigBee are? The 2.4 and 5.8 GHz devices at least have the decency of being line-of-sight and range is limited by buildings. As soon as you attach something to the wiring system of your home you create something that is impossible to manage (resolving interference issues).
Give this one to the Hams and to those of us who still own and use shortwave radios.
Tisha Hayes