HD: don't recall a mega powerful radar at Farnborough but there was one at Wisley; Cossor ASR1 or ASR3 (don't remember which) . If it was for TSR2, then it's logical as I believe it was planned to operate TSR2 test flights from Wisley. It was 23 cm and BEA apparently used to work Wisley for air tests as the coverage was far better than Farnborough or Bsoscombe.
Boscombe did have a similar radar in '72, so maybe this was the one which was at Wisley which I believe closed about this time. One of my colleagues on my cadet course (he did ADC endorsement at Boscombe) told me he'd gone to the CI in a Cherokee; on the way back he was able to be tracked on the radar from Boscombe from just north of 50N (ORTAC to you youngsters) at 2000ft, so it had phenomenal low cover!
Second thoughts, was it Decca; I seem to recall 'DASR-1' as a radar type, and Jack Wheeler(last SATCO Wisley) got a job with Decca/Plessey at Addlestone/Cowes when Wisley closed.