HR Scope

An indicator with a display somewhat similar to an "A" scope. Range is given as on an ordinary "A" scope, and height can be estimated. This is done by having the target appear as two signals by the use of two sets of antennas at different elevation angles, and by estimating the size-ratio of these two signals and referring to a table that converts size-ratio to height. An HR can also be used to estimate the size of the approaching formation of planes.