A phase-meter used for the display of Decca position-line information within a pattern.
The readings of a decometer and the lane identification meter together determine the line of position on which the craft lies.
Reference: B.S. (modified)
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Centre of buoyancy
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM