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[Pitchfork]

They work very well. However they are a problem due to RF interference. They radiate wideband interference using house wiring as an antenna... this effects some FM radios and all Short Wave/AM radio if you use it. Can also break through into audio kit if there is not sufficient mains filtering/decoupling.

A disaster for us Radio Amateurs and some Mil comms, many organisations worldwide have tried to control the spread of these things with no effect. Technically speaking these devices contribute hugely to the raising of the radio spectrum noise floor - one day we will regret this electron pollution.

Tech stuff here relating to home devices and those used for networking in urban areas: http://www.rsgb.org/emc/plt.php


 

Seconded. Except that, IME, they don't actually work very well anyway. Take the claimed throughput figures with a large pinch of salt.

You'd be much better off doing the job properly with wireless LAN or, better still, running a bit of cat 5 around the house. You'll save money, too.

Kevin

But my house is large with masonry walls (not plasterboard) so that the primary Wireless LAN does not reach the other end of the house strongly enough, which is why we send data through the mains to a second Wireless router for the other half of the house for the computers over there
You're correct, it does interfere with audio equipment (Guitar Amps & PA etc.) close by, but not elsewhere in the house

[Kevin Wood]

But my house is large with masonry walls (not plasterboard) so that the primary Wireless LAN does not reach the other end of the house strongly enough, which is why we send data through the mains to a second Wireless router for the other half of the house for the computers over there
You're correct, it does interfere with audio equipment (Guitar Amps & PA etc.) close by, but not elsewhere in the house

I take your point, but the fact remains that these devices have conducted emissions 30-40db above the EN 55022 limits to which they are declared (and required) to comply. (I have made the measurements.) They are a nuisance to anyone who uses short wave radio and, if it weren't for the fact that OFCOM are as much use as a chocolate fireguard they would be removed from the market.

I bought a pair very cheaply to use to demonstrate their effects at local radio clubs and, in trying them out at home, found them to be pretty flaky. I could hear the interference up to about a quarter of a mile away using a handheld antenna and a "toy" radio, however. To an efficient antenna  and sensitive receiver such as would be used by a radio amateur they are a menace over a much greater distance.

If they become widespread they may well end up being the final nail in the coffin for a hobby I have enjoyed since I had the sense to pick up the correct end of a soldering iron.

Kevin

[zirax]

Hmmm interesting about the background noise. What about a mega aerial for the wireless network... ala
http://cgi.ebay.co.uk/RP-SMA-2-4G-16-dbi-Wireless-Wifi-Antenna-Booster-Base-/320512806206?cmd=ViewItem&pt=UK_Computing_Networking_SM&hash=item4aa00d4d3e

That would get his house networked nicely. I presume these operate on a frequency outside radio gear? I do remember using a 10dB aerial that could connect to my mates house about a mile away at uni 

[Kevin Wood]

Hmmm interesting about the background noise. What about a mega aerial for the wireless network... ala
http://cgi.ebay.co.uk/RP-SMA-2-4G-16-dbi-Wireless-Wifi-Antenna-Booster-Base-/320512806206?cmd=ViewItem&pt=UK_Computing_Networking_SM&hash=item4aa00d4d3e

That would get his house networked nicely. I presume these operate on a frequency outside radio gear? I do remember using a 10dB aerial that could connect to my mates house about a mile away at uni 

Wireless LAN, along with video senders and a few other devices use a license exempt band at around 2.4 GHz so cause no interference to users outside that band, although they can interfere with each other.

Power line networking adaptors use a wide range of frequencies all over the short wave spectrum including broadcast bands, amateur and CB radio parts of the spectrum.

In theory that's not a problem because the signals are conducted on the mains wiring rather than radiated wirelessly. In practice, mains wiring was not designed to carry radio frequency signals and acts as quite an effective antenna, causing the signals to radiate from the house and cause problems to radio users.

The next "gigabit"* generation of these devices is even worse. The emissions extend to 300 MHz or higher so they interfere with DAB and FM radios amongst countless other things.

Kevin

*- Don't believe a word of that! Did I mention their data transfer rate figures make the average broadband providers' promises look pessimistic?

[Martin_1962]

Wire it up properly - be nice to the local amature radio fans.

[Nickbat]

Wire it up properly - be nice to the local amature radio fans.

Electro-mechanical radios, eh? Who'd have thought it possible?   

Seriously, though, I take your point. Indeed, having read all this, I'm worried that my Air Band radio will be affected, so it may have to be a hard wire. 

[KW]

so it may have to be a hard wire. 

You only have to run a single length of Cat6 (or Cat5e if you don't want to spend the little extra), and simply have a switch at the other end for any devices you want to connect.

[Pitchfork]

With 4 computers in 3 different rooms at either end of the house I don't want to run unsightly cables all over the place hence the mains borne transmission method. My netgear HDX101 only seems to interfere with audio very close by & we live in an isolated position on the very end of the overhead mains supply so probably do not interfere with any other properties

[KW]

With 4 computers in 3 different rooms at either end of the house I don't want to run unsightly cables all over the place hence the mains borne transmission method. My netgear HDX101 only seems to interfere with audio very close by & we live in an isolated position on the very end of the overhead mains supply so probably do not interfere with any other properties

Assumption is the mother of all f**k up's 

I don't want to run unsightly cables all over the place

You only need to run one cable upstairs, and then branch off from that.
If you don't want to see any cabling, then run it underneath the floorboards.