Abstract: The present invention is a moisture-insensitive system adapted to couple radio frequency energy at a low impedance from a matched two conductor transmission line, through a vehicle windshield and to an antenna in a manner which minimizes stray radio frequency radiation within the passenger compartment of the vehicle. The system includes two pair of conducting plates, one pair mounted on each side of the windshield, each pair opposite the other pair. A coaxial feed line is coupled to the inside pair of plates and a matching circuit is connected across the outside pair of plates. A full-size, unloaded antenna element is connected to the output of the matching circuit. A decoupling device, such as a decoupling sleeve or a RF choke, can be used to minimize RF current flow on the shield conductor of the coaxial feed line. The coaxial cable is coupled directly through the windshield, without an intervening matching network, so that RF energy at a low impedance is coupled to the outside pair of plates.

Abstract: An antenna mount for a vehicle includes an insulated base with an internally threaded sleeve defining a central opening in the base. A blind-type clamping assembly threads into the sleeve for anchoring the base to a body panel of a vehicle. The clamping assembly includes a clamp member with a threaded stud and integral oblong clamping flange at the lower end of the stud. A stud nut threaded internally and externally threads onto the stud and into the sleeve for joining the clamping assembly to the base. The stud joins the flange at a position offset from the geometric center of the flange toward one of its ends to subdivide the flange into two flange portions of unequal length so as to facilitate entry of the flange through a smaller than usual installation hole in the vehicle body panel and subsequent clamping of the flange against the underside of the panel through progressive threading of the stud nut into the base.