Type 284 Gunnery Radar
Wavelength: 50 cm
Power Output: 25 kw
Frequency: ~600 MHz
Accuracy: No information
Range: 10 nm / 18.5 m
Comments: Main gunnery radar used aboard large warships. In the case of Hood, it would have been used primarily to direct the fire of her 15" main guns. Hood received her Type 284 during her 16 January - 15 March 1941 refit at Rosyth. Both antennas were mounted on the rotating director hood situated above the Spotting Top.
Type 279M Aerial Warning Radar
Wavelength: 7.5 metersPower Output: 60 kW (ranging mode); 70 kW (warning mode)
Frequency: 39-42 MHz
Accuracy: Hood reported accuracy to within 3°
Range: 100 nm / 185 m (high altitude target)
Comments: It has been suggested in some books that Hood was scheduled to receive a Type 279 radar, but the installation was never completed. This is not entirely true. While Hood did not receive the Type 279, she definitely received a modified variant known as the Type 279M. It was installed during her 16 January - 15 March 1941 refit at Rosyth.
The Types 279 and 279M were largely the same with the most noticeable difference being that the standard Type 279 required two antennas (one to transmit and one to receive), whereas the Type 279M required only one transceiving antenna. This was located high above her main mast. The source confirming the installation and testing of the Type 279M is Admiralty document ADM 220/76, "Reports of performance in H.M.S. Hood, H.M.S. Illustrious, H.M.S. King George V and smaller vessels of RDF279". This document is housed at The National Archives, Kew.
Type 282 and Type 285 Allocations
According to C.A.F.O. 509, issued in March 1941, in addition to her Type 279M and Type 284, Hood was slated to receive three Type 282 and three Type 285. At this point in time it is certain that her Type 282 directors were not fitted. It is unclear however, if the Type 282 sets were fitted. There are also no indications that any part of her Type 285 radar was installed.