Abstract: An electrical module (125) is for mounting upon a circuit board (104). During circuit assembly, the electrical module (125) is placed upon a breakaway portion (117) of the circuit board (104) and a bracket assembly (103) is mounted to the circuit board (104) so as to position the electrical module (125). At the conclusion of circuit assembly, final assembly is initiated and the breakaway portion (117) is removed and the circuit board (104) is mounted into a housing (105). Preferably, the electrical module (125) is in direct contact with the housing (105) so as to maximize heat transfer.

Abstract: An electrical module (125) is for mounting upon a circuit board (104). During circuit assembly, the electrical module (125) is placed upon a breakaway portion (117) of the circuit board (104) and a bracket assembly (103) is mounted to the circuit board (104) so as to position the electrical module (125). At the conclusion of circuit assembly, final assembly is initiated and the breakaway portion (117) is removed and the circuit board (104) is mounted into a housing (105). Preferably, the electrical module (125) is in direct contact with the housing (105) so as to maximize heat transfer.

Abstract: A single-block ceramic filter (102) is coupled to two antennas (142 and 144) for providing both antenna duplexing and antenna-switched diversity in a duplex radio transceiver (100). One antenna (142) is coupled by the filter (102) to a transmitter (132), and both antennas (142 and 144) are switchably coupled by the filter (102) to a receiver (130) by diversity control circuitry (101) in response to a diversity control signal (137). A microcomputer (134) in the transceiver (100) is coupled to the receiver (130) for monitoring the received signal strength (135). When the received signal strength (135) drops in level indicating that the signal being received on one of the antennas (142 or 144) has become degraded due to fading or other interference, the microcomputer (134) changes the binary state of the diversity control signal (137) for switching the receiver (130) to the other one of the antennas (142 or 144 ).

Abstract: A dielectric block filter assembly which is surface-mounted upon a circuit board. The circuit board includes an opening formed to extend therethrough, and parallel-extending projecting members, formed of a portion of the printed circuit board, which extend into the opening formed to extend through the circuit board. The dielectric block filter includes a bottom mounting surface having notches corresponding to the projecting members. Each notch includes a seating surface for seating against corresponding ones of the projecting members in mated engagement therewith.

Abstract: A ceramic block filter (100) includes coupling pins (101 and 102) disposed in holes (124 and 125) in corresponding electrodes (121 and 122) for interconnecting the filter to radio frequency devices, such as a radio transceiver. During manufacture of the filter (100), the coupling pins (101 and 102) are bonded to conductive material (131) of the holes (124 and 125) and corresponding electrodes (121 and 122) when the rest of the conductive material (160) is fired. To facilitate the electrical bond during the manufacturing process, the coupling pins (101 and 102) may be silver or silver plated and co-fired at the same time. Since the coupling pins (101 and 102) are fired at the same time as the rest of the conductive material, a reliable and inexpensive bond is achieved between the coupling pins (101 and 102) and the conductive material of the holes (124 and 125) and corresponding electrodes ( 121 and 122).

Abstract: A duplexer for a radio transceiver is disclosed in which two volumes of dielectric material each have at least two holes and each is covered with a conductive material except for one surface. An electrode on the one surface of each volume is coupled to one of the holes and is coupled to a substrate via a terminal passing through a mounting device. The substrate provides coupling between the terminals of the two volumes and a common antenna.

Abstract: A dielectric block filter which may be mounted on a printed circuit board or other substrate as a single component is disclosed. The dielectric filter utilizes metalized hole resonators having coupling characteristics determined by the metalization pattern on one surface of the dielectric block. Input and output coupling is accomplished via terminals asymmetrically arranged in a mounting bracket. Mounting tabs on the bracket opposite a recessed area holding the dielectric block secure the filter to the circuit board and provide ground connection for the filter.

Abstract: An interdigital microstrip transmission line filter (100) includes three electrically conductive strips (104, 106 and 108) each coupled to grounded portions (110 and 120) on one end and coupled to respective capacitive loading pads (112, 116 and 114) on the other end. Input and output pads (130 and 140) may be coupled to signals from other circuitry located off or on the same substrate (150). Grounded portion (110) extends between capacitive loading pads (112 and 114) for minimizing undesired coupling between non-adjacent strips (104 and 108). As a result, the unique microstrip filter (100) has a frequency response that is substantially devoid of passband transmission zeros.