Home |
Search |
Today's Posts |
#11
![]() |
|||
|
|||
![]()
Len Over 21 wrote:
Mike, the "X10" system works at only a few hundred Hz of spectrum. I'm not familiar with the specific names. X10 is the one the power companies use? There was another system that was used to control clocks in schools and other places where the clocks need to show the same time over At no time was any part of the US electrical distribution system, home to generating plant, EVER CHARACTERIZED OR STANDARDIZED AS R.F. TRANSMISSION LINES OVER A 1 TO 80 MHz FREQUENCY RANGE! Apparently the Office of Engineering and Technology at the FCC doesn't understand that yet...? I can look out at my neighborhood's electrical distribution system and see "RF transmission lines" that must vary from several hundred Ohms to just a few Ohms within the metal conduit of my home. That is NOT any sort of "RF transmission medium" that anyone can expect to work at either smooth, easy, or trouble-free radio frequency transmission. There's discontinuities up the ying-yang there and wherever there are discontinuities, there is also the danger of even more radiation (in addition to introducing more attenuation). So if this was (is) such a good way to send signals, why wasn't the internet developed this way in the first place? For the simple reason that it does NOT work very well. :-) I guess I was kind of knowing the answer as I asked the question. 8^) It's intellectual dishonesty for those companies to try to sell it as something that will work. But even if it is a failure, some will be able to make money on it.. for while. I've got a pair of Phonex through-the-line coupled "modems" that are supposed to work between two rooms here. It's the second pair over the counter, the first pair returned because they don't work well. Second pair is no better. One good reason why they don't work is that the AC wiring in one room is on one side of the "double-phase" split from the pole drop and the outliet in the other room is on the other side. Neither Phonex or any other of the Homeplug group explains that. I can hear it now.........."We need to rewire your house to get your BPL modem to work!" 8^) I measured an attenuation from the AC outlets better than 30 db from 10 to 80 MHz, 36 db being lower limit of this setup. The attenuation is probably greater than that. No sense in improving the test setup with that much attenuation...it is already too great. Interesting. As a comparison to my cable modem hookup, There was a lot of adjusting of the line levels to get a good signal to my home office. If the installation included boosting the power enough to overcome that, there would be some serious RFI running around. I believe that I am skeptical enough that even if I didn't have a technical background, that question would pop up pretty quickly when considering BPL. Carl, is there any other way that we can aid this fight? One of the first things to try is to force an explanation of how all the vaporware BPL systems work. NONE of them explain it in enough detail to make any electronic sense right now. They haven't done so in any of the prominent electronic trade publications yet...other than more generalized, non-specific-detail claims. Vaporware. Agreed! - Mike KB3EIA - |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
How does a 6146B fail? | Boatanchors |