Radio direction-finder on board ship

Reviews the development of direction-finding. The establishment of radio beacons (1924 and onwards) using simple characteristic signals on 1000 m, a wave-length comparatively free from interference, rendered the reading of bearings independent of the skilled radio personnel of the ship. Concurrently, the direction-finder itself was simplified and more accuracy made available from it. The degree of accuracy under specified conditions is given. The errors are described under the following headings: (1) night effect error; (2) coast refraction error; (3) error due to reciprocal bearing; (4) quadrantal error; (5) convergency correction.