Here are links to a fascinating technical article on Television Detector Vans in the UK, used to track down clandestine TV viewers who neglect to pay their television licenses there. At 12 pounds GBP a month, that works out to around R3000 ZAR per annum...
The article appears in the Southgate Amateur Radio Club in the UK:
The original article in Hackaday.com is here:
Grateful thanks to Lem ZS1LEM for the info!