Monday, August 8, 2016

Harmonics

In the days when the BBC used to tell us what it was up to, the engineers of BBC Research & Development were pretty clear they had developed shirt-pocket devices capable of identifying licence fee avoiders. This is a section from their Annual Report in 2001.

PROTECTING THE BBC’S INCOME
Licence fee evasion in Britain continues to fall due to improvements in detection methods, combined with media publicity to ensure that evaders recognise the risk of being caught. Evaders are tracked down with the help of handheld detectors and a fleet of detector vans, using a national database of licence holders.

We are just completing a project to develop and document to production standard a new generation of van-based detection equipment. We have investigated a wide range of methods and chosen for development those which proved quickest and most accurate, with a view to minimising the time spent by a detector van at each target site. The new equipment is controlled by a computer, which presents a very user-friendly interface to the operator. The detection results and all relevant data are recorded automatically. We have added a satellitebased live map navigation system which helps minimise the time spent travelling between sites, as well as an automated database showing receivable transmitters at the van’s location. The equipment can show which transmitter is being received, and which channel is being viewed. The van will be in frequent contact with TV Licensing Unit’s database to check whether the viewer has a current licence. All of the equipment is contained within the van without exterior aerials. This offers the choice of covert operation, or alternately of high-profile operation simply by emblazoning the van with an appropriate logo.

We are working with BBC Technology to produce a fleet of vans with the new equipment; meanwhile, the development and testing of a further detection method nears completion. Portable detection equipment includes a handheld magnetic detector designed for use where van access is impracticable, and a shirt-pocket equivalent for covert operation.

"Detection display screen.
The graph shows TV line frequency
 and its first two harmonics."



1 comment:

  1. "BBC Technology", now there's a trip down memory lane...

    https://en.wikipedia.org/w/index.php?title=BBC_Technology&redirect=no

    ReplyDelete

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