Everything has it's place. -RickG On Sat, Nov 15, 2008 at 6:25 PM, Jonathan Schmidt <[EMAIL PROTECTED]> wrote: > Chuck is right on the spot. > > RF is very demanding both in transmission lines and radiators. We all > know how much discipline we need to invoke when deploying successful RF > links. > > RF on an unbalanced, geometrically variable conductor will barely move > with most being dissipated as heat or radiated away. Chuck is correct > that elevated, balanced three phase lines, as far as the geometry remains > stable, might have some short range applicability when coupled with notch > filters and other carefully designed, customized equipment. Short range > and expensive. That's why it isn't out there. > > The ARRL and other interested parties did observe a number of vendor > products under FCC monitoring...monitoring that was later shown to be > comparable to the Katrina effort. The results were effectively decided in > the US Court of Appeals for the District of Columbia Circuit earlier this > year: http://www.arrl.org/news/stories/2008/04/25/10064/?nc=1 > > The momentum for BPL on HV has come from investors who point to the sky > and convince people that the wires, like your cable TV coax, are > conductors and, therefore, should carry RF just like 60Hz. Anecdotal > recollections of bumbling (on both sides, I agree) experiments don't > invalidate Smith Charts and pure science. > > However, the power company has right-of-way and pole-to-pole LOS. Any of > the WISPA members would drool over that geography and would be better > shepherds of the effort to bring broadband to rural areas. > > Meanwhile, I'll go back to my Smith Charts, grid dip meter, SWR > cross-needle meter, and TDR equipment that served me so well all these > years. I run a clean shop. > > . . . J o n a t h a n > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Chuck McCown - 3 > Sent: Saturday, November 15, 2008 4:25 PM > To: WISPA General List > Subject: Re: [WISPA] IBM backs BPL > > One huge reason, powerlines are not constant impedance to RF. Nor are > they balanced. This is like trying to pump natural gas down the water > lines. > Pipe, right? What's the problem? > > It is never going to ever work as well as balanced transmission lines, let > alone coax or fiber. And it is going to leak so much that the American > Red Cross in Afghanistan will be able to detect the static on their HF > rigs. > This has been proven time and time again. > > You can get BPL to work over a short range (like a mile) if it is running > on a three phase line and the line is very balanced. Once it hits a cap > bank, regulator, transposition, transformer or anything, you have to > terminate the signal and figure a way to bypass the obstruction. > > Once you put it on a single phase line you might as well go back to the > old G-Line concept (another oddity that ultimately failed). Really BPL is > nothing more than G-Line. As long as you don't care about vomiting all > over the RF spectrum you can do whatever you want. > > I actually do listen to AM radio. I want to listen to short-wave and ham > if I decide to do so. A half baked idea like HV bpl has no place in > ruining valuable spectrum that is absolutely necessary in the event of an > emergency. > > > > > ----- Original Message ----- > From: "RickG" <[EMAIL PROTECTED]> > To: "WISPA General List" <wireless@wispa.org> > Sent: Saturday, November 15, 2008 2:41 PM > Subject: Re: [WISPA] IBM backs BPL > > >>I disagree. I personally saw BPL work and work very well. As far as >> setting up a bunch of dragonwaves, you must have line of sight. As far >> as range, whats the point? Ethernet is only rated at 100 meters and it >> is widely used. BPL's range is much farther than that. It's all >> realitive. The powergrid is already setup & ready to go, why not use >> it? Shouldnt we utilize any and all resources to their fullest >> potential? To do otherwise is wasteful. >> >> BTW: BPL is more widely used and accepted in many other countries >> abroad. Several of our potential vendors were non-US. They couldnt >> figure out the hold up is here in the states. >> >> -RickG >> >> On Sat, Nov 15, 2008 at 4:21 PM, Chuck McCown - 3 <[EMAIL PROTECTED]> >> wrote: >>> BPL on HV was and is a stupid idea. HV infrastructure was not built > with >>> the idea of being a transmission line for RF. To get any kind if speed > >>> you >>> have to use lots of power, even then it is very very short range. You >>> might >>> as well set up a whole bunch of dragonwaves in a drop and insert > system. >>> It >>> would be cheaper and work better. >>> >>> The idea of using natural gas distribution lines as circular waveguides > >>> is a >>> much more viable technology. But you don't see that getting deployed >>> either. >>> >>> BPL on HV is a lab experiment that caught the eye of Michael Powell and > >>> got >>> talked about. Nothing more. On the secondary side it is nothing more >>> than >>> homeplug. That is viable and deployed and does just fine. >>> ----- Original Message ----- >>> From: "RickG" <[EMAIL PROTECTED]> >>> To: "WISPA General List" <wireless@wispa.org> >>> Sent: Saturday, November 15, 2008 1:32 PM >>> Subject: Re: [WISPA] IBM backs BPL >>> >>> >>>> To clarify, by "real interference" I meant they are no worse than >>>> anything else we deal with. Like any RF transmission, there are >>>> emmisions, but those can be dealt with just like the way we (WISP's) >>>> deal with them. The ARRL made a mountain out of molehill and it was >>>> all political as far as I'm concened. They used the BPL as a scapegoat >>>> to try and get the electric companies to fix the interference hams >>>> receive from aging electrical insulators which causes all kinds of >>>> noise. >>>> I personally saw a perfect example of the bias against BPL >>>> interference. A parade of hams came to our pilot test site and claimed >>>> we were interferering with them then & there. The funny part: We had >>>> the system turned off! We showed it to them and they were totally >>>> embarrased and speechless. When we turned the system back on, they >>>> admitted that the noise was no worse than when it was off. We has >>>> spectrum analyzers to prove it. There are some hardliners out there >>>> that would not give up. To make their point they would drive their >>>> vehicles (equipped with ham radio and whip antenna) within a few feet >>>> and directly under the powerline and guess what? Give me break. >>>> Basically, except for a few viable installations still running, BPL >>>> was killed in it's infancy. Too bad. >>>> -RickG >>>> >>>> On Sat, Nov 15, 2008 at 1:04 AM, Jonathan Schmidt >>>> <[EMAIL PROTECTED]> wrote: >>>>> "You are correct, electric companies saw huge benefits for internal > use >>>>> but the real reason it did not move forward was because electric >>>>> companies >>>>> are conservative by nature and they didnt like the heat coming from > the >>>>> ARRL over interference issues, which btw were not real." >>>>> >>>>> The interference is real. The ARRL is real and very conservative. >>>>> And, >>>>> any conductor carrying RF that isn't a proper, geometrically arranged >>>>> transmission line, properly terminated in the proper impedance, will >>>>> radiate and radiate most of its RF energy. Where do you think that >>>>> goes? >>>>> And, where do stubs dissipate their RF?...into the 4th dimension? >>>>> >>>>> Were it not for careful oversight of the spectrum, we would be back > in >>>>> the >>>>> stone ages with AM and FM and TV because of interference. Police and >>>>> fire >>>>> radios would be hit and miss. Our licensed and unlicensed spectrum >>>>> would >>>>> be a mess. >>>>> >>>>> Blasting the HF spectrum into random lengths of conductors and stubs > at >>>>> watts of power has proved to be nasty. It isn't just the ARRL...the >>>>> courts have decided that. >>>>> >>>>> It isn't just RF on the power lines, either. You can hear DSL >>>>> interference in neighborhoods with overhead telephone wiring on poles >>>>> when >>>>> you try to listen to local AM stations at night when they are forced > to >>>>> drop their power. The political influence of the Telcos to force >>>>> through >>>>> their agenda may be followed by that of the electric companies but it >>>>> won't be to our advantage. >>>>> >>>>> They have the right of way, the poles, and the money. Stringing a >>>>> fiber >>>>> along the poles along with the wiring would seem to be a far better > and >>>>> long term strategy than to pretend that wires are wires and that 60Hz > >>>>> is >>>>> the same as 600,000Hz and the ground return and distribution are >>>>> compatible architectures. >>>>> >>>>> The entire concept is pseudo-science, appealing to those who are > easily >>>>> fooled into thinking wishes become true because it sorta makes sense. >>>>> >>>>> Jonathan Schmidt >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> > -------------------------------------------------------------------------- > ------ >>>>> WISPA Wants You! 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