HD - I think the radar you have in mind is the Cossor 901. It was in use at Boscombe Down when I was there in 1972 doing my approach radar cadet training, although it was u/s a lot of the time as I recall.
It was positioned on top of a tall concrete tower and in this clip, which seems to be part actual film and part computer game, it realistically appears 30 seconds in.
YouTube - BAC TSR2 RAF/MoD BOSCOMBE DOWN UK TEST FLIGHT XR219