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John asked in Consumer ElectronicsTVs · 4 months ago

Did TV detector vans ever work?  And do they still use them?

I've heard conflicting statements on this. 

Do they now use handheld devices instead ?   Or with flat panel LCD / plasma TVs is detection and determination of what is being watched impossible ?


How many 'goons' do they employ to go door to door ?     I was told it's under 250 for the whole of the U.K

5 Answers

  • 3 months ago
    Favourite answer

    Most of it was bluff.

    The early ones with big elaborate antennae on the outside with “GPO TELEVISION. DETECTOR VAN” on the outside actually did work a bit. They had to operate in pairs to get a triangulated fix and were a straight lift of WW2 technologies to detect spy radio transmissions.

    They sensed the emissions given off the old CRT TVs and because they weren’t very accurate relied upon the fact that relatively few people had TVs and also the fact that people were much more submissive back then to uniformed officials wearing hats.

    After television ownership hugely increased and more tower blocks were built, the vans still used much the same old technology but detection was far more of a bluff: the crews had lists of households which DIDN’T own TV Licences which by then were an increasing minority and mostly just visited properties wearing plain clothes and used their eyes and ears as primary detectors. If they saw the flicker of a TV or heard one they’d knock and back then they also had a Statutory Right of Entry: in short, they didn’t need the householder’s permission to enter the home in order to gather evidence.

    As time went on, the detection gear improved but the main methods of detection remained the same: checking lists of households with either no licence, or checking for those holding just a (much cheaper) black and white licence. Checking caravan sites and college dormitories was also an easy target as their portable TVs were only legally covered by their licence at home if they were found running on battery power alone.

    When TVs moved away from being old boxy CRTs the old detection equipment no longer worked well:  the new LCD TVs gave off very low level emissions although with a slight adjustment the (now obsolete) plasma TVs were even more detectable.

    These days lists are still the main method of detection along with much smaller handheld scanners. The handheld scanners are pretty good because they only work at very short range and are very directional. So if the detector team is near your doors or windows they can easily pick up most display screens along with a detailed image of what you’re viewing. They can usually determine whether you’re receiving live broadcasts of any kind which is an offence without a TV licence; I stress “receiving” and not “viewing”: a PVR recording live broadcasts is just as subject to needing a TV licence as any other device capable of receiving live broadcasts.

    But more than ever, detection is simply a case of checking addresses holding no licence or just a black and white licence to receive colour broadcasts. The marked TV detector vans are now a thing of the past. Also the detection teams are staffed up more heavily during big TV events, such as Easter and Christmas, Wimbledon. Tennis fortnight during major finals, major TV snooker finals, Euro and World Cup football finals, and so on.

    Source(s): Worked part time on UK TV detection for over 30 years. Still do when required.
  • 3 months ago

    TV Detectors? I don't even know the story behind that. Why would they want to know if you had a TV. Are you talking about Communists?

  • 3 months ago

    Total scare tactic.

    Zero court cases have been one using evidence of detector vans.  

    They are still being used, but agents going to unlicensed address are more effective at getting fees. 

  • 4 months ago

    Modern technology can do all sorts of things you might not expect.     

    It is wise to operate as if everything you do will be known.  

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  • 4 months ago

    They used to work because old style CRT TV's generated various radio frequency signals by the scanning circuitry used to make the pictures on the screen.

    So various oscillators in the TVs made electrical noise which you could pick up yourself by putting a radio close by.

    So TV detector vans listened out for these signals, that's how they could tell you had a TV

    With flat screen TVs you still have internal high speed switching circuits but they don't generate the same level or type of signals that old style TVs did, there is electrical noise but quite low level and different - try holding a radio close to your flat screen.

    In the old TVs, they could tell what station you were watching based on the frequency of the internal tuner oscillators, so they could say you were watching BBC or ITV in the UK, since there were originally only two channels.

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