Use of Powerline units instead of proper wifi or cables.

[SimonH2]

I am told ( by a retired but reliable source ) that the house / building from which the interference is radiating can be located without much difficulty.

Yes, basic radio direction finding. All it needs is a handheld receiver and directional aerial. Go for a walkabout, wave the aerial about till you find the general direction, move a bit in that direction, and keep repeating till you are close. Should easily get to a point where you can walk around a single house and show that the noise comes from that house.
Could be a bit more involved if there are several houses with the same problem in close proximity, but the same process applies.

Simon H is correct about how these devices fall into a gap in the regulations.

I was pretty sure I'd read that OfCon (deliberate mis-spelling ) had, for a long time, used the line that "it's not a radio transmitting station, so nothing to do with us" to get people to leave it alone.
https://www.ban-plt.org.uk/legislation.php has information on the two sets of legislation that apply.

On the subject of interference, a friend from many years ago told me a funny story. My friend was a radio amateur, but lived in the middle of a terrace. One of the neighbours had an interference problem (probably a TV with a crap RF input section) and would come round banging on the door. My friend patiently explained that he could get a form from the Post Office and the GPO (as it was back then) would investigate. But the neighbour just kept coming back and getting more and more aggressive. So my friend got a form and filled it in on the neighbour's behalf ...
You may be ahead of me at this point ...
After which, the neighbour got somewhat more aggressive because ... he got done for not having a TV licence For a finale, my friend says he got chatting to the lady in the local Post Office about a week later - and was informed that she'd sold at least half a dozen TV licences for the one street in that week

 

[ericmark]

In the Falklands the contractors shop were selling off radios rejected in the UK because they would receive any strong radio signal be it taxi, police, etc. But since few strong radio signals on the Mount Pleasant complex, they could sell them in the main without a problem.

My next door neighbour had one and was complaining my voice was coming out through his radio, I knew what was wrong, however very little I could do.

So I showed him my licence and pointed out how it said it could not be used for a broadcast receiver, I said I would call the authorities and have them check out my equipment, but just wanted to be sure he had a licence first. He decided I was likely more interesting that the one channel broadcast radio so just carry on.

It was a con on my part, as I knew the broadcast licence had been abolished, but it worked.

Also at a friends house doing experiments with slow scan TV, knock on door, are you using a TV, answer yes, have you got a TV licence, answer no, well sorry but you've been caught, but I don't need a TV licence for slow scan TV, I only need a licence for broadcast TV and this is not broadcast, here is my radio licence. Which resulted in a talk about how slow scan TV worked and it was realised their equipment at that time could not work out what type of TV I was using, latter their equipment improved and they could tell you what channel you were watching.

But TV licence laws have changed, when I wanted to use a TV set to use my computer, I enquired how I could modify TV so it was not breaking the law. At that time I was told you can't, you need a licence to have a TV even if not using it, so you have a TV so you need a licence. Some poor old lady got done for having a colour TV and black and white licence, because the VCR receives colour even if connected to black and white TV.

Today the law has changed, so you can have a colour receiver (digi box) and black and white TV and black and white licence.

Well I say law, it is more like how the law is interpreted, and this is point. The law has really always made generating interference illegal, but up to now the authorities have turned a blind eye.

 

[SimonH2]

But TV licence laws have changed, when I wanted to use a TV set to use my computer, I enquired how I could modify TV so it was not breaking the law. At that time I was told you can't, you need a licence to have a TV even if not using it, so you have a TV so you need a licence.

Are you sure ? I was under the impression that you needed a licence to USE a receiver with broadcast signals - so with no aerial connected then you were OK. I've heard a few anecdotes where "the man" has knocked on the door, and they've been invited in to see the TV showing pre-recorded videos or a computer but with no aerial connected - then left "disappointed" to have lost out on nicking someone.

 

[flameport]

I was under the impression that you needed a licence to USE a receiver with broadcast signals

It's now use any device to watch or record live TV on any channel, regardless of what that device is and how it receives the live TV - so things such as streaming live TV over wi-fi to a tablet would require a TV licence. Licence also needed to watch BBC iplayer, but not other streaming services.
Actually owning a television or anything else is irrelevant.

Given that TV licensing persons can only enter your property if you allow them to (and who would agree to that?) actually identifying whether people are watching live TV with no licence will be next to impossible.

There are other unenforceable and entirely useless rules such as if the device is battery powered, your home TV licence covers the use. Plug that device into the mains to charge and you need a TV licence at the location it is being used.

 

[ban-all-sheds]

The law has really always made generating interference illegal, but up to now the authorities have turned a blind eye.

My parents' house was less than a mile from a factory with an RF glue drying machine. When they switched that on our (and I expect thousands of other people's) VHF TV reception was wrecked. Went on for years.

 

[motorbiking]

I have a VHF radio (handheld) and some power line adapters, I held the radio right next to the adapter and didn't here a sausage. I have no way of testing if it would interfere when transmitting as my license doesn't permit use on land, but I wonder how much of a problem this is with most radios having high power mode.

 

[bernardgreen]

I held the radio right next to the adapter and didn't here a sausage.

The radiation from the mains cable may be almost zero next to the adaptor and be at maximum a few feet further away along the cable. ( standing wave nodes along the mains cable )

 

[motorbiking]

got more interference off my MacBook usb-c power cable and display. Nothing anywhere in the house - does it impact a particular channel/frequency? I'm using a standard horizon HX870, which is a pretty reasonable handheld.

 

[ericmark]

I remember the time when people could communicate from UK to USA using one watt of power, QRP was the aim of many a ham, using spark transmitters has been outlawed for years, there has been a real push to keep airwaves clean.

The woodpecker it seems was not the Russians trying to jam air waves, it was in fact a form or RADAR which it would hope followed the curvature of the earth.

There have been over time many things which have caused interference, and as their use peaks so they are in some way changed, the traffic warning system was at one time a problem, we also had CB users who decided to use same frequency as model aircraft with the clear dangers involved. Government had to give model aircraft users a different frequency.

So much today is wireless, and I have seen first hand the problems, where the room thermostat signal was blocked and the room went up to 28°C the occupant with alzheimers was in real danger of dehydration as a result.

I still use wireless links for central heating, however the new devices fail safe. But jamming radio frequencies can be life threatening, had my mother died as a result of the over temperature however the failure of the thermostat would not have appeared on the death certificate. So there are no statistics to show how peoples lives have been put in danger due to jamming of radio frequencies.

 

[bernardgreen]

does it impact a particular channel/frequency?

I haven't any detailed knowledge of ther frequency ( or frequencies ) used for the carrier(s) but have seen analyser displays with multiple peaks across a wide spectrum

we also had CB users who decided to use same frequency as model aircraft with the clear dangers involved. Government had to give model aircraft users a different frequency.

The biggest problem with CB was imported and illegal AM CB requipment ( AM Amplitude Modulated ) The UK sensibly decided that CB should be FM ( Frequency Modulated ).

AM CB knocked out hospital radio paging systems and these had to migrate to a new frequency that was within the tuning range of the receivers to avoid the need to buy several thousand new pagers. It didn't help that some CB idiots had high power "after burners" putting hundreds of watts into gain aerials. Several aerial feeders got spiked as a quick fix while the Home Office arranged for a warrant to be issued.

 

[motorbiking]

Its not power that limits range with VHF its height.

 

[winston1]

I have a VHF radio (handheld) and some power line adapters, I held the radio right next to the adapter and didn't here a sausage. I have no way of testing if it would interfere when transmitting as my license doesn't permit use on land, but I wonder how much of a problem this is with most radios having high power mode.

The older PLTs interfered between 2 and 30MHz, not VHF.

 

[SUNRAY]

The older PLTs interfered between 2 and 30MHz, not VHF.

You sure?

As a radio person - ham, PMSE, PMR, broadcast I have helped out with locating sources of interference quite a few times and seeing the noise floor right across dc to 1GHz drop by 40dB or more when the cat5 cable is removed from a PLT device is a sight to behold. Some of the older units often radiated a stronger signal than a 5W hand held radio, the newer types are definitely better.
Working in the above environments and simultaneously with BT meant I built up a fantastic relationship with the local RIS and more than a handful of times assisted their investigations (official overtime), there was nothing more satisfying after months worth of complaints, arguements etc. with a neighbouring Taxi/Ham/CB operator than unplugging a PLT device in a complainants property and seeing the interference disappear on their TV screen.
We had one where the complaints had gone on for a couple of years and a number of RIS visits where they were accusing the neighbour of deliberately not transmitting while we were attending, the fact that the complainants sun bed was not in use while we were there went unnoticed for a long time.

 

[winston1]

You sure?

As a radio person - ham, PMSE, PMR, broadcast I have helped out with locating sources of interference quite a few times and seeing the noise floor right across dc to 1GHz drop by 40dB or more when the cat5 cable is removed from a PLT device is a sight to behold. Some of the older units often radiated a stronger signal than a 5W hand held radio, the newer types are definitely better.
Working in the above environments and simultaneously with BT meant I built up a fantastic relationship with the local RIS and more than a handful of times assisted their investigations (official overtime), there was nothing more satisfying after months worth of complaints, arguements etc. with a neighbouring Taxi/Ham/CB operator than unplugging a PLT device in a complainants property and seeing the interference disappear on their TV screen.
We had one where the complaints had gone on for a couple of years and a number of RIS visits where they were accusing the neighbour of deliberately not transmitting while we were attending, the fact that the complainants sun bed was not in use while we were there went unnoticed for a long time.

Interesting. I understood the early PLTs operated up to 30MHz and the latest high speed ones extend this to 300MHz. Seems I was wrong.

All this does beg the question though why they have not been banned?

 

[SUNRAY]

Interesting. I understood the early PLTs operated up to 30MHz and the latest high speed ones extend this to 300MHz. Seems I was wrong.

All this does beg the question though why they have not been banned?

The big problem is data is digital and ideally square waves, and a square wave is made up of an infinite number of sinewaves including harmonics.
The later versions run at a lower level, or so I believe. There doesn't seem to be any standard as different manufacturers units are not compatible.

As to why they haven't been banned, the 'legitimate' manufacturers have so far been able to proove in the test lab they do not interfere according to the prescribed methods of testing.
Equally why have flat screen TV's been allowed to proliferate with all the hash they radiate?