the adjustment being varied periodically or continuously until it is halted automatically when the desired condition is attained

Full Title

Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic or electromagnetic waves, or particle emission, not having a directional significance, are being received > using radio waves > Systems for determining direction or deviation from predetermined direction > using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal > the adjustment being varied periodically or continuously until it is halted automatically when the desired condition is attained

Classification Context

Section:

PHYSICS

Class:

MEASURING; TESTING

Subclass:

RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES