Some additional information on Type 284:
The 50cm radars were first proposed in Dec 1939. An expermental set was installed on Nelson by summer 1940 but this was actually the proto 282 for pom pom direction. It used two small yagi aerials (nicknamed fishbones), one for send, and one for recieve. The beam width was 37*. After this, the equipment was converted to a proto 284 by intalling two 1/2 cylinder antennas to the main director. This antenna array recieved the nickname; "the pig trough aerial". The early version used two pig troughs, one for send and one for recieve. The range performance obtained with this set was never again matched by a production version 284. This lashed up set was removed from Nelson in Nov 1940, and Nelson was equiped with a regular production 284 during 1941.
KGV became the first warship to recieve the production Type 284 in Dec 1940. The early version type 284 did not use lobe switching and it's best bearing accuracy was 0.75* using max signal. Range resolution was 300 meters, and range accuracy was +/- 150 yards. Tests on with the KGV set revealed the following range performance:
Surfaced submarine: 6,000 yards.
Destroyer: 14,000 yards.
It was not tested vs a battleship until it was used vs the Bismarck, but the range listed is commonly 20,000 yards. KGV's 284 picked up Bismarck intermittantly at about 25,000 yards, but could not be used for spotting or consistant ranging until closer to 20,000 yards. The Suffolk's 284 was able to track Bismarck to a max of 26,000 yards. One of the interesting things about the 284 was that it had to be shut down every so often to rest the transmitting triodes. A noted point of anoyance was that there was a prolonged warmup period when re-starting the radar.
The improved 284 came available in early 1942. The new version was called Type 284I ashore, but a set modified to the new specs was called Type 284M. The new model was only first installed on new construction or on warships not already equiped with a "radio range finder". Those warships already equiped with the early model 284 had to make due until early 1943. The new model had a range resolution of 150 meters, but the Royal Navy wasn't satisfied with the range accuracy, because it deteroriated with increasing range, although it was intially better than the early model's, and far superior to the optics. The new version used lobe switching and a common mode antenna. Both the pig trough and an array of 6 yagi "fishbone" antennas could be used depending on the exact installation. The fishbones could produce a 1/2 power beam width of 4.5*. Specs for the pig trough antenna vary from source to source from 3* to 5*. Bearing accuracy using lobe switching could be as good as 0.08*, but inconsistancies in the director itself could diminish this attainment. The effective range, battleship to battleship, is listed as 29,000 yards. Historically, the Duke of York's 284M picked up the Scharnhorst intermittantly at about 35,000 yards, but the amplitude of the pip(s) was too small to fix the bearing until the range had closed to 26,000 yards.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.