Abstract: A retractable motorized multi-band antenna is adapted to receive signals in the AM/FM bands and to receive and transmit signals in a significantly higher frequency band such as that used for cellular telephone. In order to transfer the coaxial input signal to an output coaxial connector, a slip ring connector is provided. The slip ring connector is impedance matched to the antenna to create low VSWR at RF frequencies.

Abstract: In a circulator/isolator device used in a cellular transmission network, a centering ring is used to position the garnets with respect to the center conductor, magnets and pole piece. The clamping action of the housing holds the unit together. Because the ring centers all components, additional fixtures are not needed and inaccurate "eyeballing" by the assembler is eliminated. The garnets are held in place during assembly by the centering ring thereby eliminating the need for adhesive or dielectric grease.

Abstract: A removable antenna mounting device is adapted to receive an antenna such as that used for a mobile cellular telephone. The antenna is mounted to an antenna mounting member which operationally engages a trunk lid clamp member secured to the trunk lid of the vehicle. In order to provide positive engagement between the antenna mounting member and the trunk lid clamp member, an eccentric cam connection is provided. The eccentric cam connection is designed to facilitate the removal of the antenna from the trunk lid for storage in the trunk.

Abstract: A duplexing filter filters high frequency electromagnetic signals operating in two different frequency bands and uses a common coupling line mounted within an overall housing. Both filters use resonators and may be configured as combine or interdigital type filters. The high frequency filter has at least some of its resonators mounted on a base plate which in turn is positioned at a location along the length of the common coupling line so as to couple the higher frequency filter at its approximate quarter-wave location.

Abstract: A multi-band antenna is adapted to receive signals in the AM/FM bands and to receive and transmit signals in a significantly higher frequency band such as that used for cellular telephone. An AM/FM band antenna is formed of a tubular rod, and a higher frequency band antenna is formed using a centerfed coaxial dipole mounted on top of and coaxially with the AM/FM antenna. The dipole is fed by a coaxial rod attached to a coaxial cable extending through the AM/FM antenna. A cylindrical choke is disposed about the coaxial rod and is spaced a predetermined distance from the dipole antenna to reduce coupling between the AM/FM antenna and the high-frequency antenna. The choke functions to position the input impedance of the high-frequency antenna at the base of the choke in a manner so that a short matching transformer may be used at the base of the choke for connection to the coaxial cable.

Abstract: A bandpass/lowpass filter comprises a bandpass filter with two or more resonators with the first and last resonators coupled to associated connectors. Corresponding lowpass filters are positioned within the first and last resonators, wherein each lowpass filter comprises a plurality of low impedance and high impedance elements. A disk emanates from each of these integrated lowpass filters so as to couple the filtered electromagnetic energy to the bandpass filter. The overall result is an integrated filter having a desired bandpass with significant suppression of spurious frequencies. The overall integrated filter is significantly smaller than conventional filters using external inline lowpass filters.

Abstract: An n-way signal splitter having isolated outputs with a printed circuit board geometry providing the necessary crossovers with impedance lines, running under and orthogonal to resistive components, fabricated in microstrip on one side of the board, with a ground plane completely covering the other side, requiring no feedthrough holes or jumper cables to provide the necessary crossovers, and input and output connectors being fastened directly to the printed circuit board.

Abstract: An antenna base having a metal foot and plastic bezel injection molded around the metal foot to engage the metal foot. Double sided adhesive tape connects the antenna base to a non-conductive surface of a motor vehicle. In most instances this is a motor vehicle windshield. Inside the motor vehicle a coupling box connects communications signals from a signal source through the windshield to the metal foot. The coupling box supports a printed circuit board having conductive patterns on both sides for sending and receiving these communications signals. The metal foot also includes structure that allows an elongated antenna to be adjustably supported by the base in a signal sending and receiving orientation.