Broadband Over Power Lines ??

Hello Jim,

It is commonly called PLC if you want to search Google. In Germany they rolled it out in some areas and what I heard sounded like rather mixed blessings. Sustained data rates not that great, lots of EMI issues. The power grid is not at all a suitable medium for communications. Plug in a piece of equipment with really good Y-caps and your comms might go down. Then there is uncle Leroy's blender where he should have changed the motor brushes a long time ago but never got around to it. That can look like a hail storm on the analyzer.

Personally I do not believe in this technology. Just MHO.

X10 is IMHO an ill-conceived protocol. I do not understand how an on/off AM protocol could be adopted on such a noisy channel. On our X10 stuff I also found that many modules were grossly mis-aligned. Tuning them all improved things quite a bit but it is not 100% reliable, of course. Then the controllers also have issues, maybe buggy code. Once in a while they go on the fritz and you have to power cycle them.

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

It seems to have almost died given the popularity of WiFi these days. I take it you need to go further than 802.11b/g can go without more repeaters than you'd like?

If you are going to go the power-line networking route, I'd suggest something like

- it's the only one I've heard people actually say works, although of course it's seldom I talk to anyone who uses such things.

Well, X-10 was designed, what?, 30 years ago by folks who I never felt were all that horribly sophisticated; the power-line networking stuff I'm told is much more sophisticated with adaptive equalizers, better retry protocols, etc.

Let us know how it fares if you end up using it... :-)

---Joel

I've heard of it being trialled here and there but not much activity. Wireless eems to have a decent chunk of business though.

One power company here used their 'grid' as a backbone for comms but in a different way. They installed optic fibre over their HV cables ( literally wound round it IIRC ) and created a network that avoided all the issues like digging the roads up.

Graham

Hi, Jim -

Try this...

I hope you can find the information you want there.

Cheers, John

Hello Graham,

wound

That's the way to make additional money out of long distance power lines. You can string almost as many fibers and thus bandwidth as you want.

But data transfer over mains wiring is just plain wrong as an approach, IMHO. I believe it's not going anywhere as a technology.

Regards, Joerg

Hello John,

That is one problem they run into in Europe. However, ARRL mentions DSL as one of the "good" technologies and non-polluting. Well, I have DSL. When DSL runs it thoroughly drowns out strong stations around 6MHz that I like to listen to at times. With or without an outside antenna. Phone lines aren't very well shielded and the condition of the shield of a 30+ year old phone line that was just turned into a data autobahn is, well, rather uncertain. Sometimes these shields look like glorified chocolate wrappers.

wound

Yep. When I was in video engineering I tried to get people to use 75 ohm coax for power distribution, between the bays, to save all those power distribution boxes

martin

When I ordered DSL, the gal said "we have to test the line". Apparently, this particulat line had never been used for DSL, so they had to check to see if it'd reach. It took about a minute, while I was on hold. I wonder what that "test" constitutes, since this end just dead-ended at the junction box. Check for reflections a la TDR, maybe? (it was a different physical wire pair than the one I was talking on.)

Thanks, Rich

Hello Rich,

That was different here. Ok, I was the first to get DSL in this neighborhood but they still come out AFAIK. A service technician showed up with a handheld analyzer and checked the levels. Only then did he begin to mount the hardware. Afterwards he checked it again.

Well, every electricity counter here is read-out by the power provider in a remote fashion. You can press the button and retrieve your data and also the time in apparently real-time and given the amount of counters and the sensibility of the data, it seems to work pretty reliable. The new counters are fabricated somewhere in eastern Europe, and the guys who are mounting them hope to find some work in the company after the change is all done.

Wireless ? Forget that. Doesn't like steel reinforced concrete. This means it is limited to two storey wooden buildings.

Rene

PLC never had a problem when the data rate was sufficiently low. Reading out a counter can be done with 1200 baud or such.

Rene

There are a number of tests that can be run, just one of which is a TDR. A TDR is good for determining line length and finding bridge taps (stubs). Bridge taps cause a notch in the frequencies that can be used by DSL.

More likely what they did was to run a test looking for load coils and splitters first. If you have any coils or splitters on the line, they must be removed before you can get DSL. If the test showed no coils and splitters, they could then run an insertion loss measurement. From that, they could predict the bit rate you might be capable of obtaining so that they would know what they could sell you.

BTW, the abbreviation I generally see for Broadband over Power Lines is BPL.

Intellon.."creating instant networks"...but taking ages over POTs to display home page???

It will work as well as any audiophool junk...

Well, the website says they have sold five million chipsets so someone must like the way it works. I know people who work there, and I doubt they would be there if the stuff was no good.