Abstract: A microwave directional coupler which has a second dielectric board which stands erect on the surface of the first dielectric board; coupling elements are arranged with their planes facing each other on both sides of the second dielectric board, forming a coupling line part; and both end parts of the coupling line part are formed on the first dielectric board so that they can be connected by lead lines.

Abstract: An antenna has a main vertical planar part which is connected at its one end to the ground, and a main horizontal planar part which are both arranged in an L-shape. It has a secondary vertical linear part which is arranged in parallel with the main vertical planar part and connected at its one end to the feeding point. It also has a conductive secondary horizontal linear part which is connected between the main horizontal planar part and the secondary vertical linear part and is arranged in parallel with the main horizontal planar part, while being separated from the main horizontal planar part by a definite distance. This makes it possible to incorporate the antenna in the circuit board of wireless communication equipment, and the antenna is particularly suitable for miniaturizing the equipment.

Abstract: A telephone handset mounting cradle includes a housing provided along its lower edge with opposed oppositely opening grooves. The bottom of the housing includes a relief. A bracket includes opposed, facing slides for engaging the grooves and a spring clip for engaging the relief to lock the cradle to the bracket. A screw pivotally couples the bracket to a first plate about a first axis. Additional screws pivotally couple the first plate to a second plate about a second axis perpendicular to the first. The second plate includes provisions for fixed mounting to a surface.

Abstract: A microwave filter having a filtering effect against specific frequencies is fabricated by erecting a second dielectric substrate on the upper surface of a first dielectric substrate, a resonating circuit is formed by locating strip lines facing towards each other on both surfaces of this second dielectric substrate, and the strip lines are connected to input and output lines on the first dielectric substrate.

Abstract: A combination charging unit and portable, hand-held transceiver which includes a latch mechanism operable to effect an electrical connection between the charging circuit in the charging unit and the rechargeable power supply in the transceiver automatically upon insertion of the transceiver into the charging unit. The latch mechanism causes insertion of plug connectors on the charging unit into mating connectors in the transceiver in a direction which is perpendicular to the axis of insertion of the transceiver into the charging unit. The latch mechanism prevents damage to the plug connectors by exerting a predetermined constant insertion force, independent of the force employed to seat the transceiver into the charging unit, in mating the plug connectors. The latch mechanism includes a release lever which provides a mechanical advantage to the operator during the initial portion of its release movement thus compensating for the gripping effect of the plugs with their mating connectors.

Abstract: A band determining method in which radar signals of first and second frequency bands are received in the upper- and lower-heterodyne reception modes, using a local oscillation signal modulated with a low frequency signal, thus causing the phase relationship between the detected signal and the modulating signal to indicate which band signals are received.

Abstract: A radar detector capable of discriminating a prescribed radar signal from other undesired radar or interference signals by mixing an incoming electromagnetic wave radar signal with a local signal whose frequency varies with time within a fixed range of frequency repeatedly at regular periods, thus providing a beat signal; temporarily stopping the frequency sweep in response to appearance of dc components alone in the beat signal when the incoming radar signal matches the local signal in frequency; and watching the length of time for which the incoming radar signal matches the local signal in frequency. The reception of the prescribed radar signal is indicated using a sound-generating unit such as a speaker or a light-emitting unit.

Abstract: An apparatus and method for recharging a rechargeable battery in a hand-held transceiver while maintaining communications capability through the transceiver. The battery charger is housed in a charging unit to which the transceiver can be removably attached. A dual-mode charging circuit generates a first voltage during transmit mode and a second, higher voltage during receive mode, and includes a DC-DC converter for generating the second voltage. The charger includes a push-to-talk (PTT) switch and mode control circuitry for simultaneously controlling the operating modes of the charger and transceiver, and additionally includes a separate microphone, speaker, and audio and RF amplifiers for providing greater RF power and audio power while the transceiver battery is being recharged.

Abstract: A radar detector is disclosed which comprises a radar wave signal receiver for producing a detection output when the incident radar signal is synchronized with a local oscillation frequency at a certain sweeping time, first and second pulse train signal generators for producing pulses with different cycles, and a cycle alteration circuit for altering the cycle of the second pulse train signal generator in accordance with a logic output corresponding to the detection output from said receiver, thereby synchronizing such cycle with the cycle of the first pulse train signal generator. The regular radar wave signal is discerned by the detection of coincidence between the output pulses from the first and second pulse train signal generators at certain time intervals. Consequently, the radar system is prevented from responding to interference noise or extraneous radar waves.

Abstract: A selective call signal detection circuit comprises a channel free/busy state detection circuit for scanning a plurality of communication channels to determine their respective free/busy states, a present-time channel free/busy state memory circuit for temporarily storing channel free/busy detection signals resulting from the aforementioned scanning of communication channels, a past-time channel free-busy state memory circuit for receiving into storage therein in the subsequent channel scanning cycle the channel free/busy detection signals of the previous scanning cycle formerly stored in the aforementioned present-time channel free/busy state memory circuit, and a comparison circuit for comparing the signals from the aforementioned present-time past-time channel free/busy state memory circuits thereby discriminating between a selective call signal addressed to a given receiving station and selective call signals addressed to other receiving stations.

Abstract: An automatically switching circuit for the receiving sensitivity in a cordless telephone comprises a base unit and a portable handset in wireless communication with the base unit, which is responsive to the flow of charging current from the base unit to the portable handset for reducing the gain of an antenna or amplifying stage to a desired low level, thereby preventing erroneous ringing due to surrounding noise signals or disturbances while the portable handset rests on the base unit.

Abstract: Improved ringer signal circuitry in a telephone handset modifies the leading edge of the ringer signal envelope causing ringer volume to gradually increase, over a period of time, to its maximum value.

Abstract: A switching element is inserted in a power supply line to a transmission circuit in the portable unit of a cordless telephone. The charge potential which is supplied from the base unit to the portable unit actuates the switching element to break the power supply line when the portable unit is replaced on the cradle of the base unit.