(under subclass 772) Subject matter wherein the wave guide has a mass extending across the wave guide adjacent the end coupling the wave guide to free space, the mass being of material which freely passes electromagnetic wave energy.
(1) Note. The purpose of this mass is usually protection against weather, sealing the interior of the guide, or matching the guide to free space.
SEE OR SEARCH THIS CLASS, SUBCLASS:
789, for antennas within an apertured wall, which may have a closure.
872+, for antennas with housings or protective coverings.
