Abstract: The present invention relates to a fastener means for securing a center conductor (23) in a cavity filter and for enabling the center conductor to be secured mechanically in a stable fashion and with good electric contact between itself and the bottom 22 of the cavity. The inventive fastener means comprises a center conductor and a fastener element (25, 26) provided integral therewith to form a single-piece structure, which structure may have the form of a screw with the center conductor (23) as the screw head at one end and screw threads (26) at the other end. The contact surface between the fastener means and the cavity bottom is surface-treated with a material of low resistivity, such as silver for example.

Abstract: The present invention relates to an arrangement in a cavity filter for tuning the frequency relationship of the filter or its coupling coefficient factor. The arrangement includes a self-locking screw that can be fitted in the filter cavity, for instance in the center conductor, in the filter lid, or in some suitable place in the filter chassis. Tuning is effected by adjusting the position of the screw in relation to the center conductor or lid of the cavity filter. The screw can be made of metallic segments embedded in plastic, or made completely of metal, and provided with a radially through-penetrating slot. At least one part of the screw has a cross-sectional area whose extension perpendicular to the through-penetrating slot is slightly greater than in a direction along said slot.

Abstract: The present invention relates to a cavity filter (20) that includes a plurality of centre conductors which are mounted on an elevation (22) that extends along several cavities. The elevation can be produced on the bottom surface (23) of the cavity body (21) to a high degree of flatness in one single working step, and a precise measurement and precise parallelity between said bottom surface and the side walls (25) of the cavities can be obtained.

Abstract: The present invention relates to a tuning device in radio filter equipment for mobile telephony in which one or more cavities in the equipment should be tuned to the right frequency. The invention also relates to a tuning plate including a number of such tuning devices. The tuning device preferably includes regular or square formed depressed parts in the tuning plate. The depressed part converges each to a square formed central plate which is provided with an elevation or bulb. By turning a tuning screw on the equipment a force is developed on the plate and the surrounding depressed parts. This implies that the tuning can be made automatically, more secure and with less risk for intermodulation.

Abstract: The invention relates to an electrical connector (15) comprising a cable connection part (15a) and a circuit-board connection part (15b), wherein the metallic casings (16, 17) of the connection parts are electromagnetically screening and earth potential connected and include means (such as 20) for providing the casings (16, 17) of respective connecting parts (15a, 15b) with a common earth potential (5') when the parts are in a mutually coacting state. The circuit board (4) includes edge-oriented, and resilient electrical contact means (30) connected to earth potential and coacting with the metallic casing of the circuit-board connecting part. A unit provided with electrical contact devices and positioned within the electrical contact means (30) is connected by its associated connecting device or devices with a circuit-board contact surface or surfaces through the medium of connecting wires or connecting pins.

Abstract: The invention relates to a coaxial cable plug-in assembly for coaxial cables and including an electrical connection assembly. The electrical connection assembly can be connected to ground potential. The plug-in assembly includes two complementary parts. At least one of the plug-in assembly parts embraces an electrically insulating base member which is intended to accommodate a connecting device and which includes at least one through-penetrating hole adapted for coaction with a first subpart of a sleeve-like connecting device, and with a second subpart adapted for coaction with a coaxial cable whose screening conductor is intended to embrace the second subpart of the connecting device. The electrical connection assembly includes a spring-like collar which extends completely or partially around the second subpart of the connecting device for electrical and mechanical coaction between the subpart and the collar, and further includes a supportive part which coacts with the collar.