HF 200 British Height Finding Radar

A Decca HF 200 height finder at RAF Boulmer with the RX12874 Passive Detection aerial and the redundant Type 80 modulator building in the background on the extreme left. The height finding an element of the Linesman system, the HF 200 succeeded the American AN/FPS-6 height finder radars used in the Rotor system. The HF 200's (along with the AN/FPS-6) were also known as "Nodding Horrors" and they spewed hydraulic oil everywhere. HF 200 Mk3's were located at the three main linesman sites at R.A.F. Boulmer, R.A.F. Staxton Wold, and R.A.F. Neatishead. An Mk4 was commissioned at R.A.F Saxa Vord in the Shetland Islands in 1979 and there was an Mk2 at R.A.F. Troodos, Cyprus. Dave Quantrill tells me that the Troodos Mk2 featured a valve console among other things and that it was a horrible thing! Note the barbed wire in the picture; for many years Linesman sites were protected only by a wire mesh perimeter fence but in the mid '70's the Ministry of Defence must have bought a job lot of barbed wire cheap from someone because they put it up everywhere! Interestingly enough no one seems to have considered what could be done about airstrikes, mortars, and rocket-propelled grenades - the site was totally undefended from aerial attack, and the perimeter fences were not patrolled! Once upon a time all of the antennas at R.A.F. Boulmer were painted in a pale blue shade, quite pretty really, and it has been suggested that this was to satisfy the whims of the then Duke of Northumberland who happened to own the land on which the site of the operation stood, or so the story went. Eventually, though someone thought they really should be camouflaged so they were painted in a shade that in Scotland might be called "Sharnie Green"!