Lichtenstein Radar - FuG 220 Lichtenstein SN-2

FuG 220 Lichtenstein SN-2

By late 1943, the Luftwaffe was starting to deploy the greatly improved FuG 220 Lichtenstein SN-2, operating on a longer-wavelength of 90 MHz (lower end of the US VHF FM broadcast band) frequency which was far less affected by electronic jamming, but this required the much larger Hirschgeweih (stag's antlers) antennas, with only eight dipole elements, looking like a much-enlarged version of what occupied the forward end of each one of the earlier quadruple Matratze masts. This aerial setup also produced tremendous drag and slowed the operating aircraft by up to 50 km/h (30 mph). The first SN-2 set had a problem with a huge minimum range of 500 meters, initially requiring the retention of a supplementary B/C or C-1 set with its full set of four Matratze masts, but the alarming drag that full sets of both types of antennas caused, from both radars being installed, later changed the requirement to only a "one-quarter" subset of the earlier Matratze array at the end of a single mast, centrally mounted on the nose of the aircraft when the BC or C-1 UHF radar remained installed. Improvements in spring 1944 led to newer SN-2 versions with lower minimum range, which allowed the older UHF radar system to be removed entirely. In July 1944, the newest version of the SN-2 radar fell into Allied hands when a fully equipped Ju 88 G-1, of 7 Staffel/NJG 2, flew the wrong way on a landing beacon and landed in England by accident, with the crew not realising the mistake until it was too late to destroy the radar or IFF gear. This led to successful jamming of several frequency bands of the FuG 220 (I to III, 72, 81 and 90 MHz) but several other bands were still operational. After the Allied jammings the FuG 220 antenna setup was optimized for the still operational bands, the 90-degree vertical dipole setup was changed to a 45-degree diagonal setup.