Now what have I done?

Snip

There is a fishing club working party tomorrow morning!

Whatever terminates your circuit (DSLAM), the first step is analog to digital conversion. That is in effect, the "demodulator" of a MoDem.

In modern architectures, the digital samples are backhauled to some other city. Using SONET/SDH (fiber), you can drop the traffic at any number of terminating pieces of equipment, so all the power dissipation isn't in the same Central Office.

In early ADSL, termination was done with plain old IBM PC compatible boxes, rack mounted, with cards plugged into slots, one per customer. That meant a lot of wasted space (and presumably power) for the prototypes. They have made it a lot neater and tidier since then.

Your termination point (where they check the PPPOE or PPPOA username and password), might well have always been moving around. Mine moves around, when I reboot the network equipment here.

Once in digital form, you could backhaul to a termination point, half way across the country, with NO impact on results. The digital part of the trip, should not degrade the traffic. Only the analog section to the MoDem in the telco equipment, can mess things up.

I can tell you of one case though, where it is an on-premise problem.

I had an Antec power supply, maybe around 450W or so, malfunction, and on the old CRT television set, I could see a "light pattern of hash" on the screen. This was the ATX supply, dumping switching transistor noise from the front end, back onto mains. The noise would travel down the mains wire, into the SGS Thompson Modem/router and cause "Loss of Sync". Which is equivalent to a "desperately bad line condition". The ADSL signal is normally down in the soup, and to be sprayed with switching noise, was more than it could tolerate. After I replaced the ATX supply making the hash pattern on the TV screen, I was rewarded with normal Modem operation.

You could only see that on an analog TV set, not on one of the newer standards. The PC supply itself was still producing output, so no output problem was apparent.

Anything which could be touching a bare wire, could upset the line impedance and cause an impairment. But usually this would not affect all frequency bins, and only affect a few of them. If it broadly affected the line, you'd see the Loss of Sync LED pattern on the modem, and nothing would flow until it re-synched.

Paul

Ok Paul. Pretty much what the engineer hinted.

We have two TV sets linked in. The data input is rarely used so I could easily unhitch them.

This appears more likely. At the moment, speed is at 11 Mb down and

I plan to remove some tree branches touching the overhead line tomorrow and will see if that has any impact.

Addresses an issue that might cause your wallpaper to display as black when set to Stretch after installing KB4534310.

Addresses an issue that causes the stretching of a wallpaper image using non-proportional scaling to fail, and a black screen displays instead.

Prerequisite:

servicing stack update (SSU) (KB4490628) # Sometimes, it is the install of these, that "invites the others".

latest SHA-2 update (KB4474419) # That's an update required, to pick up half the # patches ever released, so you already had that...

This particular update, is a "re-release" of KB4534310, to fix problems with that update. It doesn't look like removing it, should have too much effect.

The previous update, had more technical merit. But it caused the wallpaper problem.

Those telecom lines are tough old birds. I guess we'll soon find out, whether you can grind the insulation off them, when you get up there for a look.

Just make sure they aren't power lines :-)

I think that's why they do the tree trimming around here, so home owners don't get too adventurous.

Paul

I've found its more often the termination of overheads that takes the flexing badly

They do that for power lines - telephone not so much.

Ha ha! I don't even know what wallpaper is in relation to my display!

Hmm. I downloaded the monthly security set and the big roll up at the same time but there were several m/c re-starts called for during the install process.

Other than the co-incident issue with download speed, everything seems normal.

Dropped to 5 meg. overnight! No wind and -2deg. C frost.

I'd need an access platform to get anywhere near the cable itself. Standing in the farm loader bucket is no longer considered safe with the number of mobile phone cameras walking by:-(

The support pole is in my field. I could knock it over and force a rewire:-)

The supply company have an access agreement for this purpose. The 11kV overhead has a remote operated vacuum breaker in one of my meadows. No apparent reason as there is no offtake within 1/2 mile.

You have a line problem. Get the engineers back

No rush. I'm recording a few days worth of test results as evidence.

sound plan. My ISP used to belabour OpenRetch until things were properly fixed. They can see all the bad connections on the reflectometers. It's a case of whether they can be arsed to fix them...

Right. I have a week or so results.

Tree branches removed without noticeable impact.

Curiously, but denied by PlusNet, the poor results are all when the test site says my location is Leicester. Best yet is Knebworth, just up the road!

The test site tells me *The results can be exported to CSV*. Beyond my current ken!

Plusnet prefer to deal with complaints by text message. Is there a best way to put these results on their desk?

CSV is just a basic text file, with data separated by commas. A CSV file can be read with a text editor, but all spreadsheets can import CSV files to be properly read and edited.

So I can add the file to a mail message and leave Plusnet to decode. Actually in graphical form.