UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > General Vintage Technology Discussions

Notices

General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc.

Closed Thread
 
Thread Tools
Old 1st Aug 2011, 3:01 pm   #1
Junk Box Nick
Octode
 
Junk Box Nick's Avatar
 
Join Date: Jun 2011
Location: West Midlands, UK.
Posts: 1,571
Default TV Detector Vans

I vaguely remember seeing photographs of TV detector vans back in the day of 405 line telly and if I recall correctly they were Commer vans - the ones with sliding front doors - with a couple of long conical horn type constructions bolted onto the roof.

There's a lot of myth surrounding them. Did anyone ever see one or even work in one?
Junk Box Nick is offline  
Old 1st Aug 2011, 3:12 pm   #2
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
Default Re: TV Detector Vans

Never worked one but remember them.
Do they still have them today?
I was hounded recently by the licensing authorities, I think they need some decent address/merge software in their IT systems!

Cheers.
ms660 is offline  
Old 1st Aug 2011, 3:17 pm   #3
newlite4
Octode
 
newlite4's Avatar
 
Join Date: Nov 2003
Location: Bath, Somerset, UK.
Posts: 1,804
Default Re: TV Detector Vans

See here:

http://www.autoblog.com/2008/06/09/a...detector-vans/

Neil
__________________
preserving the recent past, for the distant future.
newlite4 is offline  
Old 1st Aug 2011, 3:18 pm   #4
XTC
Retired Dormant Member
 
Join Date: Oct 2004
Location: Bristol, UK.
Posts: 837
Default Re: TV Detector Vans

Only one, and it was in the early 80s when they were doing a licence purge in the area. it looked really ancient.

I read in a newspaper that these days they don't have them because the gear has grown smaller with the rest of electronics and the inspectors have hand held TV detectors.

They may have just about worked, but I'm sure most enforcement is down to paper work, psychology and people confessing. I'm not sure that they ever successfully prosecuted anyone on the basis of detector van evidence alone.

Pete.
XTC is offline  
Old 1st Aug 2011, 3:32 pm   #5
Sideband
Dekatron
 
Sideband's Avatar
 
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,548
Default Re: TV Detector Vans

Did they ever actually 'detect' anything? Was it all just a scare factor and in fact the vans contained nothing that actually did anything? I know it was possible to detect timebase noise but it's doubtfull if you could actually determine which channel someone was tuned to.


SB
__________________
There are lots of brilliant keyboard players and then there is Rick Wakeman.....
Sideband is offline  
Old 1st Aug 2011, 3:36 pm   #6
XTC
Retired Dormant Member
 
Join Date: Oct 2004
Location: Bristol, UK.
Posts: 837
Default Re: TV Detector Vans

Mainly kidology I'd have thought.

Pete.
XTC is offline  
Old 1st Aug 2011, 3:37 pm   #7
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: TV Detector Vans

The journal of "The Institute Of Post Office Electrical Engineers" (IPOEE) certainly featured articles describing the equipment in the vans and how it worked. A portable detector was used in blocks of flats. The Post Office Gazette also ran adverts for staff to do a stint manning the vans. Applicants had to have a driving licence, be able to demonstrate the equipment to the media and be prepared to give evidence in court. The vans were regularly parked in local Telephone Engineering Centres (TECs) during the day and ventured out in the evenings at peak viewing times.

It could have been an elaborate hoax, but I doubt it.
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is offline  
Old 1st Aug 2011, 3:41 pm   #8
Skywave
Rest in Peace
 
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
Default Re: TV Detector Vans

Quote, Sideband: "I know it was possible to detect timebase noise but it's doubtfull if you could actually determine which channel someone was tuned to".

I'm not so sure about that, SB.

The local osc. will almost certainly radiate some of its signal from the aerial - albeit at a significantly reduced level, but enough for a sensitive receiver to find it and then do the necessary D.F.
In a parallel vein, at about the period in question, when I used my Eddystone 888A receiver on 10 metres with a 110' 'longwire', it used to completely block out TV reception downstairs - much to the annoyance of my parents - and the TV received field strength was substantial - you could see the TV TX mast on the nearby hill from the lounge window!

Morever, the technique of 'electronics evesdropping' (and its prevention) has been used for many years by various Government Security Agencies: look up 'Tempest' on the 'Net: same principles are involved.

Al.

Last edited by Skywave; 1st Aug 2011 at 3:52 pm. Reason: Add quote & last para.
Skywave is offline  
Old 1st Aug 2011, 4:02 pm   #9
M0ALK Richard
Tetrode
 
Join Date: May 2008
Location: Huntingdon, UK.
Posts: 78
Default Re: TV Detector Vans

I was told that the detector van would turn up at an estate somewhere and invite all the kiddies inside and show them how it worked. The kiddies would go home and tell their parents and the next day there would be a queue outside the post office of people wanting to buy a TV licence.
M0ALK Richard is offline  
Old 1st Aug 2011, 4:13 pm   #10
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: TV Detector Vans

There was a long thread on here about TV detector vans a year or so ago. It was inconclusive, but which I mean people were not convinced for or against the idea that the vans actually worked as described. Not much point in repeating it.
G8HQP Dave is offline  
Old 1st Aug 2011, 4:18 pm   #11
mickjjo
Rest in Peace
 
mickjjo's Avatar
 
Join Date: Jul 2004
Location: Dartford, Kent, UK.
Posts: 1,661
Default Re: TV Detector Vans

See:-

http://www.britishtelephones.com/veh...htvans/023.htm

There was a discussion about this in this thread last year from post # 64 :-

https://www.vintage-radio.net/forum/...tor+van&page=2

Some were real but a lot were fakes.

Regards, Mick.
mickjjo is offline  
Old 1st Aug 2011, 4:38 pm   #12
julie_m
Dekatron
 
Join Date: May 2008
Location: Derby, UK.
Posts: 7,735
Default Re: TV Detector Vans

Of course, if you knew what IF the detector vans used (I'm presuming, not unreasonably, that they were superhets) you could, with a sensitive enough receiver, build a TV detector van detector; which would pick up the detector van's local oscillator and automatically switch off the TV as soon as a TV detector van was detected .....

Having a free choice of IF, you'd not be quite so vulnerable to a TV detector van detector detector!

Why wasn't a smartcard reader mandated for all digital receivers, whether combined or separate, from the outset? Then the BBC could have just issued viewing cards for their programmes, and had automatic licence fee enforcement with no need for heavy-handed tactics.
__________________
If I have seen further than others, it is because I was standing on a pile of failed experiments.
julie_m is offline  
Old 1st Aug 2011, 5:16 pm   #13
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
Default Re: TV Detector Vans

When colour arrived,it was the 4.43Mhz Oscillator that was detected and of course it cost much more for the licence.

David
HamishBoxer is offline  
Old 1st Aug 2011, 5:19 pm   #14
Skywave
Rest in Peace
 
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
Arrow Re: TV Detector Vans

Indeed, AJS: ECM (electronic counter-measures) & ECCM (electronic counter-counter measures) are at the core of your suggestions, re-your paras. 1 and 2. And in certain, well-guarded corridors of power, the associated technology & its implementations are kept well under wraps. I can say no more.

Al. / Skywave.
Skywave is offline  
Old 1st Aug 2011, 5:21 pm   #15
Skywave
Rest in Peace
 
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
Arrow Re: TV Detector Vans

Quote:
Originally Posted by HamishBoxer View Post
When colour arrived, it was the 4.43MHz oscillator that was detected.
In which case, detecting the local oscillator radiation - and thus deducing what channel the set was tuned to - would also have been possible.

Al.
Skywave is offline  
Old 1st Aug 2011, 5:39 pm   #16
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
Default Re: TV Detector Vans

Is anyone in possesion or restoring any of the tv detector stuff?
I guess TV detection will be a thing of the past soon.

Cheers
ms660 is offline  
Old 1st Aug 2011, 5:48 pm   #17
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 7,059
Default Re: TV Detector Vans

It would be great for a Forum member to find and restore an old detector van! Not much chance though, I bet...

Quote:
Originally Posted by Skywave View Post
In which case, detecting the local oscillator radiation - and thus deducing what channel the set was tuned to - would also have been possible.
How? I thought that by the time colour TV arrived, both the BBC and ITV timebases and colour subcarriers were so accurately generated that you couldn't distinguish between them
kalee20 is offline  
Old 1st Aug 2011, 5:54 pm   #18
Boom
Retired Dormant Member
 
Join Date: Jan 2007
Location: Westbury, Wiltshire, UK.
Posts: 2,451
Default Re: TV Detector Vans

Quote:
Originally Posted by Sideband View Post
I know it was possible to detect timebase noise but it's doubtfull if you could actually determine which channel someone was tuned to.
Wouldn't the identification offset used by stations show up on the line timebase? It is this which causes two seperate but locked pictures to be seen if received together (??)
Boom is offline  
Old 1st Aug 2011, 5:57 pm   #19
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
Default Re: TV Detector Vans

The 4.43 was picked up to determine that there was a set running and if the location didnt have a licence then i guess there was a loud knock on the door.

David
HamishBoxer is offline  
Old 1st Aug 2011, 6:06 pm   #20
mickjjo
Rest in Peace
 
mickjjo's Avatar
 
Join Date: Jul 2004
Location: Dartford, Kent, UK.
Posts: 1,661
Default Re: TV Detector Vans

Quote:
Originally Posted by kalee20 View Post
It would be great for a Forum member to find and restore an old detector van!
The only known Commer TV detector van to survive has been restored:-

http://www.***********/photos/29485695@N02/5666139441/

Took about 6 years:-

http://66.129.69.181/forum/topic.asp...8&whichpage=20

Regards, Mick.
mickjjo is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 1:38 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.