Yield limit

A value determined by the manufacturer to be the failure strength limit of a coupling component that will cause detrimental damage. If this limit is exceeded, the coupling should be replaced.

Y Cut Crystal

A piezoelectric plate cut from a quartz crystal in such a way that the plane of the plate is perpendicular to the Y-axis of the crystal. See CRYSTAL AXES and Y-AXIS,

Yagi Antenna

Also called Yagi-Uda array or beam. An antenna consisting of two or more parallel, straight elements, including at least one parasitic element and at least one driven element. The elements all lie in the same plane. Each driven element is connected to the feed line, half-wave resonant, and center-fed. A two-element array can be formed by adding a director or a reflector alongside a single driven element. An array with one director and one reflector, along with the driven element, increases the gain and directivity compared with a two-element system. The gain and directivity increase further as elements are added. This is usually done by placing additional directors in front of a three-element array. Compare QUAD ANTENNA.

Yield Strength

The lowest stress for plastic deformation of a material, below which the material is elastic and above which it is viscous.