| 摘要 |
A mobile two-way communication antenna is mounted on a metal plate which is pivotally secured to a housing so as to pivot about a horizontal axis. An electric reversible motor drives an elongated screw which in turn moves a cam surface linearly. The cam surface coacts with the metal mounting plate for moving the plate and the antenna between a horizontal and a vertical position. Horizontally extending ground plane elements are provided in applications where the housing is nonconducting. These elements contact the metal mounting plate when the plate is in its full upright horizontal position.
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