I haven't heard much about television detector vans lately but we used to be told that they could detect a television even if it was switched off and they could even tell which room it was in.
How do such detectors work?
[I know nothing about electronics but my guess is that televisions contain circuits that resonate at characteristic frequencies*. When those circuits have electro magnetic radiation of those frequencies directed at them, they resonate and re-emit those frequencies and such emissions can be detected. Something like that.
I'm using the phrase "characteristic frequencies" loosely.]
They don't apply so much anymore, mainly because of technological changes.
CRT displays, have a number of deflection coils that direct the electron beams to where it's supposed to go. The coils that do this were driven by the analogue video stream, and the signal is easily discernible by relevant radio receivers and directional antennas.
LCD displays don't use such driving technology, so can't be sensed with any real accuracy. Same goes for PC tuner cards that translated the TV display to a different resolution even though you may have a CRT monitor attached to the computer.
However, doing that (TV vans) proved expensive.
The more reliable method, was to look up the database of who's already paid up, assume that *everyone* has a TV, and just doorknock asking why they haven't paid up yet.
The usual suggested course of action is to avoid them (so they need to come back at a later time, hopefully getting tired of the exercise), or leave them at the front door (there is no legal requirement to bring them in) and simply state you do not watch the BBC (which are the only channels legislated by these fees).
Of course, if you don't have a TV, you could invite them in and show them (they'll take note and not bother you again). Or if feasible, hide the TV, but might prove difficult if you have a
240" monster hanging off the wall. PC attached tuner cards are more difficult to prove, they're not immediately visible, and the guys in suits are not rocket scientists, and if it doesn't look like a TV it probably ain't a TV.
If you really *don't* watch the BBC, good luck to you, you're going to have a fun time trying to prove it.
dunno. it's pretty hard to detect a TV that's turned off.
Old style CRT tvs emit emit electromagnetic waves magnetic waves from that magnets that control the vertical and horizontal scanning of the electron beam.
To detect LCD tvs they probably use a directonal microhone and listen for the audio track of the TV shows.
** Only details I ever read involved picking up spurious local oscillator ( ie VHF ) radiation from the TV set emitted via the owner's antenna using a directional loop on top of a van.
Don't think it has been done much since the 1960s.
Actually, a few years ago a local radio ham got prosecuted for not having a TV license. He ended up in court and proved his case. I don't remember the details but it ended up in the local papers and eventually made national news. I do recall that the whole episode made the TV enforcement people look quite silly.
Here in Australia, I never watch the ABC. (Similar to the UK BBC, it's public funded, except we pay for it via taxes, not separate fees like in the UK).
Truth be said, I *can't* watch it due to circumstances of positioning and terrible antennas. That said, I watch very little commercial TV either for that matter.
Anyway, we also had separate fee payments like the UK before some politician before my time thought it would be a good idea to bundle it up and do away with visible fees. Quite sensible actually, amazing that a politician had come up with the idea...
I don't have the patience to explain myself to them like that. I'd be more likely to tell them to get f%#ked if they came round every so often. Much like the Mormons and the Jehovas. I don't pay attention to
*their* particular brand of program material either.
This isn't true; watching ***any*** TV broadcast requires a TV licence in the UK. Incidentally, one genuine exemption, foreign-language satellite programming uplinked outside the UK was abolished in 2004.
No "program" was abolished, an exemption was. (Is English not your first language?) Until 2004, UK residents were exempt from the need for a licence provided they only watched channels, from a non-EU country, via satellite, provided that the channels was uplinked to the satellite from outside the UK.
Yes, in fact it is. It's obviously not be yours, however. Hint: the independent clause doesn't modify the subordinate clause. In this case "abolished" doesn't modify "exemption", rather "programming".
Then why didn't you say that (and I thought I used too many commas).
Ah, I stand corrected. I've just checked (which oddly enough is what I should have done in the first place) and yes, there are two licence fees, one for colour, one for black and white.
There are exceptions, such as if you're over 75, or if you're blind. I don't get the bit that old foegies get TV for free, but if you're blind, you still have to pay. Half price, but still have to pay.
What's REALLY odd, if you're blind there are still TWO licensing models, one for colour and one black and white.
Ah, money gouging with bureaucracy at it's best.
I'm pretty sure at least a couple had replied no, turned off TVs cannot be detected.
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