Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[GigabitEthernet]

This is why I'm hoping a mains conditioner where the modem is might stop the noise from the mains?

[sevenlayermuddle]

I would argue that any interference is most likely picked up by the telephone wiring before it reaches the modem.   In that case a mains conditioner would make very little difference but I am certain this is an inexact science so who knows, try it, and if it works just be grateful.


Another thought ocurred to me earlier.  Obviously, any imbalance in the phone wiring, such as a non-filtered ring wire, would mak matters worse.  But what about imbalance in the mains wiring, would that make matters worse too?   I'm not an electrician, but I'd speculate that mains imbalance might be worsened by some fault conditions, such as a break in just one conductor of a ring circuit.

Another factor might be the house earthing system.   With  many, but not all, domestic installations, I understand rhat the 'earth' is simply bound to nuetral in the meter cupboard.  If earth is bonded to neutral then all earth bonding within the home, to water and heating pipes, kitchen sinks, etc, are in effect directly connected to neutral and, not sure, but maybe acting as a radiating antenna?    The extent of earth bonding depends, I believe, on when the wiring was installed as regulations change in time.  But  might all that make a difference, presenting imbalance that worsens interference from power line adapters, but varies a lot from one home to another?

Stress again, I am not an electrician.   And I am most certainly not suggesting anybody start checking out their own mains wiring, or earthing systems, very dangerous territory.   But I would welcome discussion on these points, especially from anybody better qualified than me?

[JGO]

In response to sevenlayermuddle,  my experience in high power RF systems is that the RF performance of power wiring is a lottery.
I believe years ago the IEE set an exam calculation involving a 50 Hz power transmission line about 1500 Km long. Power engineers were puzzled to find more volts came out than went in, because they KNEW that was impossible ! RF engineers just said " Ah, quarter wave at 50 Hz   OK".   
This is the key point, power engineering ignores everything but 50 Hz so systems are not designed with any RF consideration.  When it comes to not just transmission but possible interference, as far as I know  only Radio Amateurs are, (certainly were)  required to have any knowledge of the subject.

In other words using a power connection for information is a lottery; if it works consider yourself lucky. If not forget it don't whinge !

[sevenlayermuddle]

Thanks for that, JGO.

One hypothetical scenario that concerns me, but doesn't seem discussed too often, is where some neighbouring household uses power line data, my phone line happens to pass their property, and the lottery conspires against... So my connection would be adversely affected, but difficult to prove the cause, and no comeback even if proven - since the devices have all required approvals.

Personally I think the very fact these devices might, in some common circumstances cause major problems, should be enough to have them banned.  The accepted fact that they sometimes do not cause problems, at least to DSL connections, should be no excuse against the fact that they might.

If we can ban proper light bulbs, and ban powerful vacuum cleaners, and ban whatever else, why can't we just ban power line data - at least for domestic use?

[JGO]

Personally I think the very fact these devices might, in some common circumstances cause major problems, should be enough to have them banned.  The accepted fact that they sometimes do not cause problems, at least to DSL connections, should be no excuse against the fact that they might.


What about banning cars or electricity supply which do cause injury or death ?
 Unfortunately we  have to use sense if we don't want to live in a nanny state.

Suggest decent power line filters would mitigate the case you suggest; the transfer is supposed to be conduction not radiation.

[sevenlayermuddle]

The difference with an electricity supply, or driving a car, is there are a set of carefully considered rules that govern how the technology is used.  The rules are set in statute and as long as the rules are followed, the risks are reduced to a level that has been deemed to be acceptable.

I am not convinced the same argument applies to Power Line Adapters.   It seems to me that no matter what rules are followed it will be largely a lottery, whether or not they cause problems.  And even if they do not cause a problem to the user's broadband, they may unkowingly affect somebody else's broadband, or somebody else's Radio reception.

But I see this issue has actually been done to death by Ofcom and even debated in parliament, plenty of requests to have them banned, with no agreement to do so.   Most recent hits from a recent search suggest Ofcom were thinking about prosecuting the users of problematic devices, which seems a tad harsh, as 99% will have not the slightest concept what they've done wrong.

See from a couple years ago, not sure what came of it?

http://www.ispreview.co.uk/index.php/2015/01/ofcom-propose-prosecute-owners-bad-powerline-network-adapters.html

[JGO]

You seem to be arguing that when something may cause interference it should be illegal, but not something which is known to be lethal ?

[sevenlayermuddle]

No that is not what I was arguing at all.

Not sure how my words came across that way, but I'll refrain from trying to explain these points any further as I'm not even sure why we are discussing lethal dangers of electricity supply, and car accidents, in the context of power line adapters?

[Chrysalis]

I agree they should have been banned, but ofcom are past that point now, there is so mucb widespread use of the devices they wont be banned unless its determined at some point in the future they cause a health hazard.

[sevenlayermuddle]

I agree they should have been banned, but ofcom are past that point now, there is so mucb widespread use of the devices they wont be banned unless its determined at some point in the future they cause a health hazard.

Or maybe spin a yarn that they contribute to global warming?

Actually that may not be so far fetched.   I don't know how much power they consume.  It'll be tiny I'm sure,  but since they will often be on 24/7, the energy saved by banning them might be comparable to other items banned in the name of climate change.

[JGO]

Why mess about  ?   A fibre-optic data link is proof against most things short of an atomic bomb. I worked on one about 1960 and the 100kW transmitter from which the data was coming didn't bother it at all.

[sevenlayermuddle]

Why mess about  ?   A fibre-optic data link is proof against most things short of an atomic bomb. I worked on one about 1960 and the 100kW transmitter from which the data was coming didn't bother it at all.

I'm impressed.   

I started Uni in early 70s and when we first toured the engineering labs there were various fibre optic projects going on.  First time I'd seen that technology in the flesh, all seemed very cutting-edge and futuristic, though istr the various projects were more about analogue transmission of voice/video, vs data?

We're verging off-topic mind, hope we don't get scolded.

[c6em]

Why mess about  ?   A fibre-optic data link is proof against most things short of an atomic bomb. I worked on one about 1960 and the 100kW transmitter from which the data was coming didn't bother it at all.

Not so fast...
The fusion joins in fibre optic are very susceptible to freezing conditions being the location where the fibre is exposed from its sheath.
Water gets into the joining enclosure, freezes and then crushes the fibre which totally messes up its transmission properties.  Known problem in countries which get seriously cold.

[JGO]

The fusion joins in fibre optic are very susceptible to freezing conditions being the location where the fibre is exposed from its sheath.
Water gets into the joining enclosure, freezes and then crushes the fibre which totally messes up its transmission properties. 

OK but Powerline Adaptor wiring used in place of an Ethernet link would be indoors ? well mine would !! .