Quote Originally Posted by ronstew
I wrote
I am told that specially equipped trucks roam through British neighbourhoods looking for the electromagnetic emissions of unlicensed TVs.

Moose McLennan replied
I think that one falls under the category of 'urban legend'.

So I looked into it. The UK TV Licensing authority claims that they do use the vans. Link.

This wikipedia article states that evidence from the vans has never been presented in court.
Actually the link I posted to the BBC's article showed one of the vans and talked about how that is just what they are doing. Driving around looking for signals and knocking on doors to give citations.