Abstract: The invention relates to a card-type attenuator having a flat insertion loss from DC to 2 GHz or higher. A rectangular card has two ground conductors extending along its longitudinal side edges and an inner conductor extending along a first face of the card midway between said ground conductors. The outer conductor comprises two main parts: First, a metal trough into which the card is placed with the two ground conductors, and secondly, an inverted U-shaped metallic spring which has its free ends pressing against the ground conductors respectively to hold them firmly in the trough. The inner conductor is accurately positioned a distance from the bottom of the trough which is small compared to the distance that the U-shaped spring is above the inner conductor. Hence, most of the electromagnetic field exists between the inner conductor and the bottom of the trough. Accordingly, the exact size and shape of the U-shaped spring is not critical.

Abstract: A microacoustic signal processing device for propagation of shear bulk waves in a substrate. A preferred embodiment of the device includes a substrate having opposed, polished principal and second surfaces. An input interdigital transducer supported on the principal surface includes a plurality of aluminum electrodes photoetched on the principal surface; a ZnO layer overlying the electrodes; and a conductive aluminum film overlying the ZnO layer. Shear bulk waves propagated by the input transducer are available for processing at various locations on the principal and second surfaces of the substrate.

Abstract: A low profile camouflaged antenna for military vehicles and the like. The tenna comprises an elongated, typically rectangular, sheet of metal curved to conform to the curvature of the vehicle. Insulated spacers, for example of plastic or fiberglass, maintain a fixed spacing between the metal plate and the vehicle, thus forming two elongated slots which, when suitably energized, act as a dual-slot antenna.

Abstract: A variable equalizer wherein a series circuit which consists of a voltage source and an impedance circuit having an impedance Z.sub.x is connected in parallel with a circuit for changing an input voltage into a current, and an impedance circuit having an impedance Z.sub.y is also connected in parallel with this current source. The voltage value of the voltage source is made one which is obtained by multiplying the current by a value proportional to 1/Z.sub.y, and the impedance circuit having the impedance Z.sub.y is endowed with a frequency characteristic.

Abstract: Insular waveguide band reject ring resonator filter and band pass ring resonator filter built for use in the frequency range from about 1 GHz to about 1,000 GHz, which filters may be used either with a single pole or multiple poles.

Abstract: High frequency electrical cable is provided in accordance with the teachings of the instant invention wherein a plurality of conductors for transmitting information are contained in a common sheathing. Each of the plurality of conductors takes the form of a central core of insulating material upon which a layer of conductive material is rigidly disposed. The thickness of the layer of conductive material is such that current penetration is substantially independent of frequency within a given frequency range. Therefore, within this frequency range the attenuation characteristics of the resulting cable are substantially independent of frequency.

Abstract: A base station radio antenna comprising a bracket having a first section for attachment to a support structure and a second section for receiving antenna whips, an antenna whip extending upwardly from a central opening in the second section of the bracket, and a plurality of antenna whips inclined relative to the upwardly extending antenna whip and extending generally downwardly from openings in the second section spaced radially from, and equi-angularly around, the central opening.

Abstract: Digital transversal filter for realizing a lowpass filter with a cut-off frequency f.sub.g and an impulse response h.sub.1 (i), a lowpass filter having a cut-off frequency 2f.sub.g which has a transfer characteristic which is in phase with the first-mentioned lowpass filter, as well as a lowpass filter with a quadrature transfer characteristic of the in-phase filter.

Abstract: A boresighting antenna for receiving signals within a given frequency band is covered by a radome having a wall including dielectric material. Boresight error compensation is provided by one or more pairs of perforated metal plates. Each plate has a dielectric material thereon. The plates of each pair are positioned symmetrically in relation to the longitudinal axis of the radome forward of the antenna in the radome in the direction from which the signals are received, and are tilted forward toward the radome axis from the interior wall of the radome at such an angle as to provide a phase lag in frequency components of the received signal at the high end of the given frequency band and a phase lead in frequency components of the received signal at the low end of the given frequency band.

Abstract: A microwave multiplexer having a plurality of comb-line filters tuned to pass distinct but adjacent frequency bands connected in parallel to a common input through individual resonant circuits having a minimum impedance at a frequency in the pass band of the associated comb-line filter.

Abstract: A plate having a hexagonal opening for mating with a hexagonal coupling disposed at the base of an antenna is lockably secured to an element of the antenna mounting platform to preclude threaded disengagement of the antenna and its coupling from the platform.

Abstract: A switchable attenuator assembly includes a housing, a plurality of rocker arms mounted for pivotable movement within the housing, and a pair of shorting bars associated with each rocker arm. Each shorting bar of the pair of shorting bars associated with each rocker arm is coupled to a respective end of the rocker arm and is aligned with electrical connectors which extend from an attenuator circuit aligned with and adjacent to the housing. The rocker arms are selectively pivoted to cause the shorting bars coupled thereto to move into and out of engagement with their respective electrical connectors to provide attenuation of selected magnitudes to an external circuit.

Abstract: A switchable attenuator includes a split housing assembly formed of interlocking cover and support members. A plurality of rocker arms are mounted for pivotable movement between the cover and the support members and each rocker arm has lugs formed on opposite ends thereof which receive respective ones of a pair of shorting bars. Electrical circuit connectors, coupled to an attenuator circuit mounted adjacent to the support member, are aligned in pairs with each pair being positioned to receive a respective one of the pair of shorting bars associated with each rocker arm. The rocker arms are selectively pivoted to cause the shorting bars to move into and out of engagement with the electrical circuit connectors aligned therewith to selectively provide attenuation of different magnitudes to an external circuit.

Abstract: An attenuator, which can readily provide balanced as well as unbalanced attenuation in a plurality of external circuits, includes first and second circuit substrate devices and an actuating device associated with the circuit substrate devices. The first and second circuit substrate devices each provide variable magnitudes of attenuation to respective ones of the external circuits such as, for example, signal transmission lines. The actuating device couples the first in the alternative, and second circuit substrate devices simultaneously or the first and second circuit substrate devices separately to their respective external circuits so as to produce desired magnitudes of balanced or unbalanced attenuation in the external circuits.

Abstract: The radiation absorber system of a unidirectional spiral antenna is provided with a laterally transverse variable radiation absorption density characteristic to control the absolute gain with frequency pattern, i.e. absolute gain versus frequency characteristic, of the antenna.

Abstract: An antenna matching network for matching a citizens band radio transceiver to a standard automotive whip or windshield antenna utilizes a matching section for matching the nominal 50 ohm output of the citizens band transceiver to the generally lower impedance of the automotive antenna. A trap tuned to the citizens band prevents the output of the citizens band transmitter from damaging the automotive broadcast receiver when transmitting. The matching section is tunable over a sufficient range to match the citizens band transceiver to most automotive antennas, and a dual sensitivity indicator is utilized to aid the operator in tuning the matching network to provide optimum matching without the use of specialized equipment.

Abstract: An omnidirectional circularly-polarized antenna system includes a plurality of dipoles equally spaced in a horizontal circle about a metal support mast. The dipoles are tilted at an angle with respect to the plane of the horizontal circle to excite circularly-polarized waves. The dipoles are fed in phase rotation with adjacent dipoles 90.degree. out of phase.

Abstract: An offset FED magnetic microstrip dipole antenna consisting of a thin eleically conducting, element formed on one surface of a dielectric substrate, the ground plane being on the opposite surface with the radiating element shorted to the ground plane. The length of the element determines the resonant frequency. The feed point is located along one edge of the antenna length and the input impedance can be varied by moving the feed point along the edge of the antenna to obtain optimum match for the resonant mode without affecting the radiation pattern. The antenna bandwidth increases with the width of the element and spacing between the element and ground plane.