Masprodenkoh Kabushikikaisha

Maspro Denkoh Co., Ltd.

Masproh Denkoh Co., Ltd.

Toshihiro Sugiura

Hiroshi Matsubara

Shigemitsu Toriyama

Masahiro Otsu

Masanari Hiramatsu

Yoshiro Hoshino

Tsuneyuki Inayoshi

Kazuyoshi Nakayama

Eiji Shibata

Akira Hayakawa

Masamune Takeda

Takashi Tamezane

Wataru Kodama

Junichi Takahashi

Chikahiko Nakane

Yoshiji Hattori

Hironori Goto

Junichi Inaguma

An interference exclusion capability testing apparatus is provided for use in testing interference exclusion capability of a specimen by radiating an electromagnetic wave toward the specimen from a radiating antenna. The radiating antenna includes an electromagnetic horn, and a waveguide plate that guides an electromagnetic wave radiated from the electromagnetic horn to the specimen.

Interference exclusion capability testing apparatus

A connector for a coaxial cable has a connector body and a securing ring. The connector body includes a tubular insertion section that is insertable between an insulation member around a core conductor of the coaxial cable and a woven conductor around the insulation member, a flange section that is provided around the insertion section and with which both the woven conductor of the coaxial cable and a cover member around the woven conductor come into contact when the insertion section is inserted in the coaxial cable to position the insertion section, and an annular fitting section that is provided at the insertion section, on the opposite side of the coaxial cable, and into which an object to be connected is insertable. The securing ring is used to pressure-bond and fix the coaxial cable to the insertion section from the periphery of the coaxial cable after the insertion section of the connector body is inserted in the coaxial cable. The connector has a fixation section for fixing the connector body and the securing ring together.

Connector for coaxial cable

In an immunity test system of the present invention, a boundary point detection device changes a signal level of a transmission signal input to an antenna through a level adjusting device while monitoring an operation of an electronic equipment, and thereby detects a signal level of the transmission signal at a boundary point, at which the electronic equipment is changed from a normal operation state to an abnormal operation state, or vice versa, due to the test wave; and a test result storing device calculates an electric field strength of the test wave at the boundary point by using conversion data based on the signal level of the transmission signal at the boundary point detected by the boundary point detection device, and stores in a storage device a calculation result of the electric field strength as well as a test condition used for obtaining the electric field strength.

Immunity test system

A coaxial cable connector having a stopper in a main body for supporting the circumference of the coaxial cable and preventing the coaxial cable from falling out. The stopper is a ring-shaped fastening portion provided in the main body and whose central axis is the same as that of the main body, and a supporting portion which protrudes from the fastening portion in the direction of the central axis of the main body. A rotation-stopping means constituted by a strip-shaped projection is provided on at least an inner surface of the main body to engage the circumference of the coaxial cable. When an end of the coaxial cable is inserted into the main body from behind, the stopper prevents the fall-out of the coaxial cable because the supporting portion supports the circumference of the coaxial cable, and the strip-shaped projection prevents rotation of the coaxial cable.

Coaxial cable connector and electronic device case

In a CATV trunk amplifier, a downward signal input to an input terminal from the center equipment side is input to a downward amplifying circuit via a first filter and a second filter. The amplified downward signal is output to the terminal device side via the second filter, the first filter, and an output terminal. An upward L signal is input from the terminal device side via the output terminal to an upward L amplifying circuit via the first filter and a third filter. The amplified upward L signal is output to the center equipment side via the third filter, the first filter, and the input terminal. An upward H signal is input to an upward H amplifying circuit via a fourth filter. The amplified upward H signal is output to the center equipment side via the fourth filter and the input terminal.

CATV trunk amplifier, upward signal amplifier, and bi-directional CATV system

An external noise intrusion prevention device preventing intrusion of external noise into a central conductor of a trunk cable in an up signal frequency band is provided. A first filter circuitletting a signal in frequencies of 54 MHz or higher pass is provided between an input terminaland an output terminal. A front filter circuitand a rear filter circuit, which constitute a second filter circuit, are provided on both ends of the external noise intrusion prevention device, respectively. A noise elimination circuitformed by cascading two connection transformersandis also provided. The two connection transformersandare connected to each other while being arranged in a line symmetrical manner.

External noise intrusion prevention device, signal amplifier, protector and antenna plug

The invention provides a noise elimination device that can be installed easily on a coaxial cable and that can effectively eliminate noise from both the center conductor and the outer conductor. Coaxial connectorsandare provided on both ends of a tube-shaped housingmade of an insulator, and a coil made by winding a coaxial cable of thin diameter is around an open magnetic ferrite core is disposed inside the housingand connected to the connectorsandat the two ends. The earth-side connector thickness of the outer conductor of the coaxial cable and the connector as well as all earth-side conductors, such as shield membersconnecting the connectors with the outer conductors of the coaxial cable, is at least 0.1 mm.

Noise elimination device and method for installing the same

In a cable broadcasting system of the invention capable of setting output or stop of broadcasting-signals from tap output terminals of a tap device in response to a command signal transmitted by a center equipment, when demand for output setting for many tap devices occurs, output setting of the corresponding tap devices can be surely carried out without increasing the load on each power supply device for supplying the tap devices in each district with electricity. When demand for setting tap output of plural tap device occurs, a head-end controller reads output setting data for all the tap devices which are the objects of tap output setting and transmits command signals in order to tap devices at a rate of one tap device per each district covered by a power supply device. The interval of transmission of command signals to one district is controlled to be longer than or equal to the time &#x394;tn necessary for the tap device to which a command signal was previously transmitted to finish tap output setting operation.

Cable broadcasting system

A primary winding of a first insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an input terminal, and windings of a noise eliminating transformer are provided within balanced lines on the side of a secondary winding of the first insulating transformer. A primary winding of a second insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an output terminal, and balanced lines on the side of the secondary winding of the second insulating transformer is connected to the noise eliminating transformer. One end of each of the primary windings, which is grounded to the ground line, is connected to the middle print of the secondary winding of each insulating transformer. Noise components having the same phase inputted from both electrodes of the input terminal are cancelled at the primary winding of the first insulating transformer, and the remaining noise components are completely eliminated through the noise eliminating transformer and the secondary winding of the second insulating transformer.

Noise eliminating apparatus of high-frequency transmission system

A primary winding of a first insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an input terminal, and windings of a noise eliminating transformer are provided within balanced lines on the side of a secondary winding of the first insulating transformer. A primary winding of a second insulating transformer for balance-to-unbalance transformation is connected between the central electrode and the outer electrode of an output terminal, and balanced lines on the side of the secondary winding of the second insulating transformer is connected to the noise eliminating transformer. One end of each of the primary windings, which is grounded to the ground line, is connected to the middle point of the secondary winding of each insulating transformer. Noise components having the same phase inputted from both electrodes of the input terminal are cancelled at the primary winding of the first insulating transformer, and the remaining noise components are completely eliminated through the noise eliminating transformer and the secondary winding of the second insulating transformer.

Frequency converter for an antenna

An apparatus for receiving satellite broadcasts comprises a frequency converter for outdoor use to which a receiving antenna is to be connected and a station selector for indoor use to which a television receiver is to be connected, the converter and the selector being connected to each other by a transmission line. The selector supplies the converter with a station-selection signal corresponding to a channel as chosen by the user, through the transmission line. Upon reception of the selection signal, the converter picks up the channel signal corresponding to the selection signal from a number of different broadcast microwave signals intercepted by the antenna, and sends the selected signal to the selector through the line. The signal is then received by the television receiver.

Growing community of inventors

Nisshin, Japan

Toshihiro Sugiura