Before revision: A 1983 Leyland Sherpa television detector van at the Postal Museum, London TV detector vans are vehicles which, according to the BBC, contain equipment that can detect the presence of television sets in use.
After revision: A 1983 Leyland Sherpa television detector van at the Postal Museum, London TV detector vans are vans which, according to the BBC, contain equipment that can detect the presence of television sets in use.