> What do they contain? Do they do anything at all?
>
> I recieved a letter today telling me, incorrectly, that I haven't got a license. I can understand how they could check for a license, but how can they check for a TV?
>
> A (terrestrial) telly intercepts transmissions using an aerial. As far as I know, it does not broadcast anything. So how do those vans that stalk our streets work? Can an unlicensed TV actually be detected? Can a licensed one, for that matter?
>
> Tub"Big Brother is watching me, but he needs new glasses"ba

I've only ever seen TV detector vans in British 1960s-era "Punch" cartoons. In NZ the moronic annual broadcasting fee was recently scrapped (yay!), but all the years it was in force, I have no idea how they knew who to send a bill to. I had a feeling they might pin down TV owners by some sort of mailing list supplied by TV retailers. But we had a succession of hand-me-down TVs obtained for free, and once we got a bill for one of them. Later, after buying a new TV from a shop, this never resulted in a bill. Now I wonder if it was completely random, on the assumption that just about every home has at least one TV, and since almost nobody ever pays the broadcasting fee, it's a safe bet *someone* at that address will be racked with guilt on receiving the dread notice.