Openreach engineers 4th visit...

[Dave Liquorice]

"Remote" as in all it needs is a fibre connection from the network. Getting power can be quite a problem, wayleaves etc, and is expensive, piggy back power from the customers and whole new areas become available.

Why bother with the hassle in an urban area when a single cabinet adjacent to the distribution cabinet will do the lot? All without disturbing the distribution cabling, either to bring several houses connections into the same chamber or install the required fibres for each node probably all the way back to the nearest agregation point which almost certainly isn't at the local exchange.

FTTRN is far more useful when you have a small number of places <1 mile from the same cable joint that also has nearby access to fibre. Where the costs of installing a "traditional" powered cabinet would never be recouped.

[The Natural Philosopher]

Simply too much of a coincindence. And I have te stats to prove it.

I see you dont really know much about corroded joints.

or indeed arcing, and how and why arcing makes a bad joint worse.

[Roger Hayter]

I don't think enough of the power in your arc fault is going to end up in the telephone wire. Calculating how much is beyond me, but the mutual inductance is going to be of the order of nanohenries to one wire, and if the telephone wire is a twisted pair the whole point of this is to reduce the induced voltage to a small fraction of what would occur in a single wire. I really doubt if it would be enough to damage the joint. The whole point of coincidences is that statistics don't apply to single events. Otherwise no-one would ever win the lottery.

[Dave Liquorice]

I have a TP-Link TL-MR3020 (about £20) and ZTE MF831 dongle (eBay, new but Russian "Beeline" branded, works fine think it was a tenner).

That's the tricky bit. 1st step is to find which network actually has useable 4G where you are. Around here that's EE only, Voda and 3 are

3G, O2 2G! Then you need to be able to tether. Mine is a backup so no on going costs meaning PAYG. All that narrows down the options to not very many, it has an Asda Mobile PAYG SIM in it, their best offering is £25/15GB/30 days.

It doesn't so much fall of a cliff as just keep getting slower and slower. Openreach don't market (wholesale...) lines that they don't think will achieve at least "superfast" (>25 Mbps) speeds.

We are about 2.5 miles from the cabinet which is across the road from the exchange. Our line is not availabe for VDSL. About a year ago they upgraded the ADSL to ADSL2+ and we got a huge speed increase from about 5 Mbps to just under 6 Mbps.

[Dave Liquorice]

Upload uses the bottom end frequency range and is far less affected by the line length than download. But yes the upload on ADSL2+ is normaly around double that of ADSL.

according

6 miles and 1.2 Mbps down strikes me as quite good. The village below us struggled to reach 0.75 on 4 miles. They now have FTTC.

24 GB would last about a week here... and we aren't using anything like the amount of data we used to when the kids were home. 24 GB might have lasted a couple of days back then.

[Dave Liquorice]

No the induced voltage in each wire is pretty much the same, twisting them just helps ensure that variations in field strength are evened out in each wire thus reducing the common mode (ie between the wires) voltage even more.

Both wires will still have the induced spike and almost certainly a circuit somewhere to cause some current to flow, if only the capcitance to ground of several miles twisted pair.

And don't forget in the rest state of a phone line there is 50 V DC across the pair and there was some noise on the line before hand indicating a poor connection. Does TNP have any proper bells on the line? The energy required to drive those might have kept the iffy connection clean or broken it completly.

[Dave Liquorice]

Some one call?

[Dave Liquorice]

Mainly because you already have "superfast" broadband. The more recent FTTP that is popping up around here is in places that have no "superfast" broadband and are a dozen or so properties reasonably close together and the existing copper is on poles. There maybe underground FTTP going in as well but poles with fibre at the top are easy to spot as thay have a square, bright yellow, "CAUTION OVERHEAD FIBRE" warning plate on them, they are often replacement poles as well.

[jrwalliker]

The overhead fibre cables seem to be quite strong. I have seen several half-fallen trees held up by overhead fibre - one of them for well over a year. John

[MissRiaElaine]

You could be right, our feed is underground, no poles in the street at all.

[The Natural Philosopher]

So you don't accept that a lighning strike close to a cable induces enniugh voltage ot be a problem?

you talk about inductance, You dont seem to understand capacitance.

If - and its a bit of an if - the cables are riouted te way I think they are, the lighting T & E passes with 3 inches of that junction box.

Peak current was enough to flip the 60A main breaker. Or the RCD

[The Natural Philosopher]

is that huge?

Thats about what this line did under similar circs but upload went from

448k to >1Mbps.

[The Natural Philosopher]

a junction box is not that twisted.

No. Panasonic PABX only.

I think both wires went high WRT to earth vi probably capacitative coupling and the local end is probably eartthed in some way. And tehre was a micro arc that burned away the resisitive connection leaving a nasty diode type one of oxide.

[The Natural Philosopher]

naturally they run then with somethimg like high tensile steel wire as well....

[Martin Brown]

External antennae and a Mifi that accepts them will get you a wider range of carrier options but the data charges do sting a bit.

Some round here only get 16M - the copper lines are all ancient and the joints most probably all corroded and waterlogged. They dug one black junction box up in my front lawn a couple of years back and it sounded like maracas when the guy shook it with the water rattling round inside.

From my perspective the download improvement was about like yours but the increase on the upload speed was much more noticeable doubling from a puny 448k to 1M. Still slow enough to be a PITA but a very definite improvement over the previous offering.

[Roger Hayter]

Just a clarification, current induced in the same direction in both wires is common mode, the difference in current or potential between the wires is differential mode. Otherwise I agree with your point, just noting that the common mode impedance is not well defined and probably high making it difficult for much common mode current to flow.

[dkol]

All cabinets do.

Because 100' at most of copper to the house performs a lot better than 1km or more of copper does.

All without

They already do in the street.

or install the required fibres for

The fibre loops through the boxes.

[Roger Hayter]

A problem I have often suffered. Especially bad for telephone input circuit MOVs. Energy in your arc, perhaps 2kA for 0.1sec (but probably only 5msec) at 240v approx 5 x 10^5 joules, most likely less. Lightning discharge perhaps 1 x 10^9 joules.

I guess the inductive coupling is till much bigger than the capacitative. But if you insist we could work it out. The microwave components of the discharge may bave to be modelled by antenna theory, too.

[Roger Hayter]

Sorry - 5 x 10^4

[The Natural Philosopher]

is on the edge of 'near field. BUT let's say peak 400V at say 60A. That is 24KW of power.

Way more than enough to cause a spark in some adjacent wiring.