Hi Stephen,
Sorry I got the wrong idea about your interference, Interesting you mention Process Automation, was this factory type use
where on screen diagrams of plant equipment, are controlled remotely using Avantec PC Cards and wire similar to CAT6 etc?

I am not totally against smart meters themselves, but the way people are being lied to, to have them fitted
Some web comments, say they do not read accurately, It would be interesting to Add a normal old rotating disc meter
after the smart meter, and do some measurements, to see if this claim is right, or just urban myth
But to do a proper test, would need doing with a reactive load, that was not a good power factor

Any weak Medium wave signals can be brought up in level, with device called a frame or loop antenna
this is a simple passive device, that you place near to a portable AM radio, making a huge improvement in signal level

The simplest of these, can be bought from Ebay or Ali express or amazon etc, for under £20 if you shop around
Type say, Tecsun AN200 into ebay, but don't pay £30-£45 for one, The AN200 is about 9 inch. diameter coil, which is quite small

but, If you are good at basic DIY woodwork, a larger one can be easily built, for even better results
My original one, is around a metre square, in my roof/ loft space, away from mains wiring etc...amazing results

Usual cause of AM interference, that I have heard, is ADSL from LandLine phone overhead pole wiring
Not Likely to improve in the future, as it will take years to fit everyone, fibre to the home, instead of copper wire

As pointed out in posts below, it's the cheap imported things, using switch mode psu's, that cause interference
Some, have been found, to have the original design filter parts, left out inside, replaced with wire links (to save £)
so if you can keep the antenna/ radio, away from any mains wiring, that may contain switch mode hash, it will help


Rod Watts