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[NewtronStar]

In essence, the majority of devices with a switched mode power supply that I looked at, that came from the Far East, were illegal in terms of EMC compliance.

It is coming up to that time of year again when we install are modern crimbo trees with fancy led lights and switched mode power supply and fancy electronics to change the phaze & colour of these led bulbs and which impacts our VDSL signal in the home this effected the FEC's it just went crazy

Lets hope the Billion 8800NL copes better this Christmas with this offending Xmas tree as the HG612 & BB2 hated it

[sevenlayermuddle]

Not directly related to REIN, as such, but my findings may shed some light on what's going on with unlawful RF emitters....<much deleted, but read!>

Fascinating insight, Jeremy, welcome to the debate.

I had always assumed that the radiating equipment was legal, if inconvenient, but perhaps not always so.

Regarding CE marking vs reality, I can't help wondering if there might be a comparison with EU diesel emissions standards vs reality?   But that is a whole different Pandora's box that may be better left unopened.   

Back on topic, somewhere buried on Kitz forums I documented some massive RF interference that I traced with near certainty to a local house that had suffered flooding, and had a flood abatement pump installed.   These pumps seem to be remotely controlled by modulated (analogue)  RF signals over mains, with obviously detrimental results.   Out of sympathy to the victim of the flood I decided not to complain but still, slightly astonishing that such a device would be legal.

[JSHarris]

I'll admit to being astounded by the level of fraud going on when it comes to CE safety marking.  Until I started looking at LED power supplies, I had no idea that flagrant disregard for EMC (and LV safety) standards was so widespread.

The problem seems to be just cost-cutting by the far-eastern manufacturers.  None of the switched mode LED power supplies that I looked at had any RF shielding and none had any form of supply filtering.  They typically operated at a few hundred kHz  and all of the ones I looked at sent pulses at the switching frequency directly to the LEDs, down unscreened wires.

There's long been a rumour going around that the letters "CE" on any Chinese made electrical equipment really means "China Export" as far as the manufacturers are concerned, and that many unscrupulous suppliers deliberately make this marking look near-identical to the EU approval mark.  An added problem is that approval is delegated, so when a product arrives in an EU state with a CE mark, there is an automatic assumption that the manufacturer has conducted the appropriate testing and certification.  Sadly, this is never checked, so fraudulently marked products can easily make their way into our homes.

The level of interference generated by a reasonably powerful switched mode power supply, with no shielding or filtering is easily powerful enough to cause interference to a wide range of equipment, and sadly copper phone wires make pretty good antennas, so are almost certain to pickup interference of this level.

[Black Sheep]

It may also be worth noting that in my experience, not all 'noise' heard using the handheld-radio detecting method is actually service affecting noise.

Only in the last month myself and another engineer found a PSU (for a BT Business system as it goes  ), that was so 'Noisy', it could be heard on the van radio for a distance of two terraced blocks either side of it. However, it had no effect on the actual DSL spectrum.
We still haven't found the true source as yet.

[NewtronStar]

The Radio detection of two foreign radio stations 5990 Khz and 7330 Khz is definitely service effecting noise as it causes lower SNRM in the evenings 

[aesmith]

It may also be worth noting that in my experience, not all 'noise' heard using the handheld-radio detecting method is actually service affecting noise.

That's interesting because one of the OR guys who was out on a broadband call with us did a scan with a little portable radio, picked up quite a loud noise from our PVR but he didn't think it significant.  Said something along the lines of we could move it further from the router if we were worried.   Subsequently my tests showed that neither error rate nor noise margin are affected by switching that equipment on or off.

Do you have a tester that can pick the noise up from the line, so you can match it's signature to the frequency and pattern heard on the radio?

[Black Sheep]

That's interesting because one of the OR guys who was out on a broadband call with us did a scan with a little portable radio, picked up quite a loud noise from our PVR but he didn't think it significant.  Said something along the lines of we could move it further from the router if we were worried.   Subsequently my tests showed that neither error rate nor noise margin are affected by switching that equipment on or off.

Do you have a tester that can pick the noise up from the line, so you can match it's signature to the frequency and pattern heard on the radio?

Oh how I wish, sir !!!! 

The Precision Test Officers (PTO's) have  such devices offered to them, but us lesser mortals have to make do with our experience and guile. 

The kit that they have will capture the footprint of the 'noise' as shown on their Spectrum Analyser, (Forget the radio - that is purely to aid with faulting only if REIN patterns have been confirmed on the SA).
They then attach their Directional Antennae and sweep around in arc's until the same trace appears on their 'Footprint screen'.

I only request a PTO in perhaps 5% of cases, if that !!! I can only assume other REIN engineers across the country are similar ...... as such, I'm guessing there isn't a business case to supply us with the necessary expensive equipment the PTO's have

No doubt there's a few folk on here that could probably knock up something very similar from a Cornflakes packet, a coat-hanger and an old crystal radio set ?? 

[Black Sheep]

As an aside ........... I've found (often enough) that when driving near premises that have solar-panels installed, the radio will scream at 612Khz MW, but they have no effect on the DSL bit-loading at all.

I know from embarrassing personal experience, after I was telling the occupant of one house (in a smug way), how his solar-panels make our radio's scream at us, and that it's naughty for broadband signals. I looked a right dick when it was proved otherwise. 

[aesmith]

That's interesting, presumably it's the invertors making the noise and maybe propagating it onto power cables.   I wonder if that's what our man picked up with his van, miles from our house and phone cables but near to two small wind turbines.    Was it a sort of harsh 50Hz buzzing?

Sent from my Nexus 7 using Tapatalk

[Black Sheep]

That's interesting, presumably it's the invertors making the noise and maybe propagating it onto power cables.   I wonder if that's what our man picked up with his van, miles from our house and phone cables but near to two small wind turbines.    Was it a sort of harsh 50Hz buzzing?

Sent from my Nexus 7 using Tapatalk

Indeed. I've just had a quick look for a sound-byte that used to be available on our internal web-pages, but can't seem to locate it ??
If you've driven under the large overhead electricity transmission cables with your radio playing, which I'm sure you have  , then the buzzing noise that produces is very similar. 

[stevebrass]

No doubt there's a few folk on here that could probably knock up something very similar from a Cornflakes packet, a coat-hanger and an old crystal radio set ?? 

That's it - Cornflakes! All these years I have been using Rice Krispies and could not get rid of the snap, cr.............

[tbailey2]

Some 4 years ago I had a terrible time on ADSL2+ with REIN that caused immediate resyncs and loss of d/l speed. Eventually traced it to a neighbours faulty inverter PSU within their monitor. "Oh yes it keeps turning off out after an hour or so and have to leave it  for half an hour before switching it on again...." 

Anyway,  here are some recordings I made from a portable Roberts radio around 612kHz wandering around outside if that helps.

REIN Quiet

REIN Active

[konrado5]

tbailey2: I have sometimes similar REIN.
http://www.filedropper.com/buzzing
It sounds as hum noise.

[sevenlayermuddle]

Time for a slight reallity check perhaps, as this thread seems to be switching between RFI and REIN? 

They are not the same thing.

[NewtronStar]

REIN can be cured if the source is found and can be replaced to stop it effecting the ADSL & VDSl frequency spectrum, RFI cannot be cured as it is most likely a Radio Transmitter which is effecting certain frequency's in the ADSL & VDSL spectrum yet they both interfere with broadband the same way.