Abstract: The diversity antenna circuit comprises a first antenna for receiving a vertical plane of polarization of an electric wave, a second antenna for receiving a horizontal plane of polarization thereof, a receiving means for detecting the electric field strength of a received signal, a first matching means for matching the first antenna to the receiving means, a second matching means for matching the second antenna to the receiving means, a first transfer means, a second transfer means, a first switching means, a second switching means, and a switching control means for connecting one of the first and second antennas to the receiving means and separating another one from the receiving means according to ON/OFF control of the first and second switching means based on received electric field strength.

Abstract: A cordless telephone set having a base unit and handset units and enabling communications using a channel selected from a plurality of channels. The cordless telephone set comprises apparatus for storing a specified number of channels selected by the telephone apparatus and storing historical channel use data. Whether or not a channel is unused is determined and channels used with high frequency with the data stored in the first storage are changed to those used with low frequency according to the historical use data. Channels that are stored are progressively specified prior to a start of call and a specified channel is selected, if it is determined that the channel is an unused one.

Abstract: A cordless telephone set having a base unit and handset units and enabling communications using a channel selected from a plurality of channels. The cordless telephone set comprises apparatus for storing a specified number of channels selected by the telephone apparatus and storing historical channel use data. Whether or not a channel is unused is determined and channels used with high frequency with the data stored in the first storage are changed to those used with low frequency according to the historical use data. Channels that are stored are progressively specified prior to a start of call and a specified channel is selected, if it is determined that the channel is an unused one.

Abstract: A cordless telephone consisting of base and handset units is disclosed wherein a control circuit incorporated in the base unit comprises first and second D/A converters, first and second A/D converters, and first and second sync. signal generation circuits. The first and second D/A converters respectively convert digital signals from the handset unit and a PBX. The first and second A/D converters convert the analog signals provided from the first and second D/A converters to transmit them to the PBX and handset unit, respectively. The first sync. signal generation circuit regenerates a first clock signal synchronously with a sync. signal provided from the PBX to render the first A/D and second D/A converters to operate in synchronism with the sync. signal from the PBX. The second sync. signal generation circuit generates a second clock signal which is independent of the sync. signal from the PBX to render the first D/A and second A/D converters to operate in synchronism with the second clock signal.

Abstract: A parent telephone set comprises a transformer, a sidetone level reducing circuit, and a first secret talk processing circuit for executing digital secret talk processing, a counterpart slave telephone set comprises a second secret talk processing circuit for executing digital secret talk processing, a delaying circuit for delaying an aural signal from the slave telephone set microphone by a specified delay time, and a level reducing circuit for reducing the level of output from the second secret talk processing circuit according to the output from the delaying circuit. The specified delay time in the delaying circuit is set according to the time required for digital secret talk processing in the first secret talk processing circuit as well as in the second secret talk processing circuit.

Abstract: A cordless telephone consisting of base and handset units is disclosed wherein a control circuit incorporated in the base unit comprises first and second D/A converters, first and second A/D converters, and first and second sync. signal generation circuits. The first and second D/A converters respectively convert digital signals from the handset unit and a PBX. The first and second A/D converters convert the analog signals provided from the first and second D/A converters to transmit them to the PBX and handset unit, respectively. The first sync. signal generation circuit regenerates a first clock signal synchronously with a sync. signal provided from the PBX to render the first A/D and second D/A converters to operate in synchronism with the sync. signal from the PBX. The second sync. signal generation circuit generates a second clock signal which is independent of the sync. signal from the PBX to render the first D/A and second A/D converters to operate in synchronism with the second clock signal.

Abstract: An antenna device for a radio transmission-reception apparatus is disclosed which comprises an antenna element which is to be electrically and mechanically connected to a printed-circuit board fixed in a housing of the radio transmission-reception apparatus, an inverted U-shaped hollow reinforcement spacer, an antenna cover and a retaining portion formed on the housing. The reinforcement spacer has a hole formed in the top portion thereof a diameter of which is substantially equal to that of the antenna element to slide therethrough, a slit formed continuously from the hole to a base end thereof through which said antenna element can be entered in the reinforcement spacer, and a flange formed around the outer circumference of the base end. The antenna cover is constituted to accommodate therein the antenna element with the reinforcement spacer, and has a flange formed around the circumference of a base end thereof.

Abstract: A cordless telephone apparatus detects the received field strength in a receive channel, as viewed from the base unit side, and if the field strength is below a prescribed level outputs an out-of-range signal on a receive channel, as viewed from the base unit side. The remote unit is provided with a volatile memory area for storing channel connection state data indicating whether or not two-way radio communication was established between the remote unit and the base unit. A backup power source enables the contents of the volatile memory area to be maintained even if there is an interruption in the supply of power from the battery in the remote unit. A call resumption control circuit to resume transmission of call information from the remote unit when internal power in the remote unit is supplied from the battery.

Abstract: For removing the variation of resonant frequency of the 1/4 .lambda.g coaxial resonator, which is caused by the external connection as a result of conventional capacitive coupling, a 1/4 .lambda.g line having both ends opened is coupled to the 1/4 .lambda.g resonant line having one end shorted through distributed inductive coupling, so as to provide a basic structure of the dielectric resonator of the invention, which can be arranged in usual various types of circuits such as filters, multiplexers and the like with excellent and stable performances.

Abstract: A dielectric waveguide-type filter is fabricated by vapor depositing or coating all but one of the four sides extending in the axial direction of a six-sided dielectric block that is long in its axial direction lying perpendicular to its width and height with a conductive material and either leaving the fourth side surface open or forming it with a conductive pattern depending on whether the filter characteristics to be obtained are high-pass characteristics, band-pass characteristics or band-rejection characteristics, the conductive pattern, if formed, being formed in a configuration and distribution depending on the filter characteristics to be obtained. A pair of electrode patterns for electrical connection with an exterior circuit are provided by patterning of conductive material on the opposite axial end surfaces of the dielectric block or on the open surface at positions near the opposite axial end surfaces.

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 workpiece bite device having a pinch member provided at a side for biting a workpiece in a pair of flat cutters which are disposed with those working blades facing each other for rolling the workpiece. The pinch member is fitted to a cutter body such that a starting portion of the pinch member is positioned at a side for charging the workpiece rather than a starting portion of the working blades of the cutter body, a terminal portion is positioned at a side of the working blade starting portion of the cutter body, and a top of the pinch member protrudes higher than a top of the working blade starting portion.

Abstract: A rolling flat cutter having finishing blades corresponding to corrugation of a product to be obtained by working a tubular or cylindrical workpiece, and a method of rolling by the flat cutter. When the workpiece is worked, a pair of flat cutters are disposed such that the finishing blades face each other, and the cutters are moved rectilinearly in opposite directions perpendicular to a direction in which the finishing blades extend so that the corrugation is formed on a periphery of the workpiece from an end to the other in an axial direction thereof. As to the rolling flat cutter, a flat cutter is used which comprises a rectangular cutter body, a triangular blade base formed as a higher step on one side of a plane of the cutter body along a straight line parallel with a diagonal of the plane, and the finishing blades are formed on the blade base.

Abstract: A method of rolling with flat cutters having finishing blades for rolling a periphery of a pipe. In working, the pipe is rotatably supported at both ends by a pair of centers, a pair of flat cutters which have a plurality of corrugated finishing blades formed on a substantially triangular blade base are disposed such that the finishing blades face each other and the directions of the finishing blades are parallel to an axis of the pipe, and the flat cutters are moved rectilinearly in opposite directions to each other from an initial working position to a terminal working position such that one end of each finishing blade presses the pipe. Thus, the periphery of the pipe is progressively worked axially from one end of the pipe.