In about 1969 I found a 20mm Oerlikon cannon still laying alonngside its mount at the Pevensey CH radar station. It was in a brick revetment, alongside its cone-shaped mount. Although minus its ‘inards’ it was substantially intact. We carted it back to 54 Sqn (Eastbourne) ATC although it was later taken away by the Police! I have a press cutting photo of it somewhere. Incredible that it was still there. The mount and revetment are still there.