Abstract: An ion generator 100 of the present invention includes a charging section 103, a transformer 104, an ion generating element 105, a switching element 108, and a drive section 107 for controlling the switching element 108 to be turned on or off. The switching element 108 is (i) turned on after completion of electric charge by the charging section 103 and (ii) turned off during a time period between T/4 and T/2, where T is a resonant cycle which is determined by inductance of a secondary coil 104b of the transformer 104 and capacitance of the ion generating element 105.

Abstract: A power supply apparatus includes a printed circuit board having the longitudinal direction and including first and second regions where AC and DC circuit components are mounted respectively. A first heat dissipation plate and a second heat dissipation plate provided to stand respectively in the first and second regions each include, as seen in a plan view, a linear first straight portion and two second straight portions extending respectively from the two ends of the first straight portion in opposite directions respectively and in the longitudinal direction. Respective first straight portions of the first and second heat dissipation plates are opposite to each other, and one of the second straight portions of the first heat dissipation plate and one of the second straight portions of the second heat dissipation plate are partially opposite to each other.

Abstract: A satellite antenna switching apparatus has LNB ports to which LNBs are connected, receiver ports to which receivers that exchange signals with the LNBs are connected, cascade ports to which another switching apparatus is cascade-connected, and impedance circuits that function as means for detecting the signals exchanged between the LNBs and receivers. The impedance circuits provide impedances according to the connection states of the cascade ports, and are electrically disconnected from the signal paths when another switching apparatus is cascade-connected to the cascade ports. With this configuration, the satellite antenna switching apparatus suffers from less attenuation of the exchanged signals even in a cascade connection of a plurality of stages of switching apparatuses.

Abstract: Coil(s) 11 and coil(s) 12 of LC resonant circuit(s) are oriented such that their centers are mutually perpendicular. For example, coil 11 might be mounted so as to stand upright on printed wiring board, and coil 12 might be mounted so as to lie flush against printed wiring board. Such configuration permitting lines of magnetic force from coil 11 and coil 12 to be oriented so as to be mutually perpendicular, lines of magnetic force from coil 11 and coil 12 do not merge, and coil 11 and coil 12 are not electromagnetically coupled. Accordingly, inductances of respective coils 11, 12 are unchanged; impedance frequency characteristics of respective LC resonant circuits are maintained at what they should be; and resonant impedance(s) is/are not lowered.

Abstract: A high impedance circuit of the present invention includes an LC parallel resonance circuit for raising circuit impedance, and a diode, which is connected in parallel to the LC parallel resonance circuit, causing a loop current to flow back via the diode and an inductor in the LC parallel resonance circuit so that a counter electromotive force, due to a surge voltage, which occurs across the inductor is cancelled. A low noise block downconverter which includes a high impedance circuit having a high impedance prevents peripheral circuits from being destroyed by a counter electromotive force, due to a surge voltage, which occurs across the inductor. For this, a diode is provided to cause a loop current to flow back via the diode and the inductor so that the counter electromotive force is cancelled.

Abstract: The present invention is a low noise blockdown converter (LNB) capable of ensuring sharing of specific information between or among a plurality of microcomputers. In the event that receiver 15 is connected to I/O port 14c assigned to slave microcomputer 13, slave microcomputer 13 may receive inquiry or inquiries from receiver 15 for information specific to LNB 11. Upon receiving such inquiry or inquiries, slave microcomputer 13 may, by way of bus 16, request that master microcomputer 12 provide specific information. Upon receiving such request or requests, master microcomputer 12 may, by way of bus 16, provide slave microcomputer 13 with specific information stored in advance at master microcomputer 12. Slave microcomputer 13 may send this specific information from I/O port 14c to receiver 15.

Abstract: The pin pitches on the respective edges of a plurality of selectively mounted semiconductor devices match one another, and the distances between the edges differ from one another. Shared lands are arranged so as to correspond to contact pins disposed on one edge of the respective semiconductor devices. Accordingly, selectively mounting a plurality of types of semiconductor devices onto a printed circuit board is achieved while saving space.

Abstract: Coil(s) 11 and coil(s) 12 of LC resonant circuit(s) are oriented such that their centers are mutually perpendicular. For example, coil 11 might be mounted so as to stand upright on printed wiring board, and coil 12 might be mounted so as to lie flush against printed wiring board. Such configuration permitting lines of magnetic force from coil 11 and coil 12 to be oriented so as to be mutually perpendicular, lines of magnetic force from coil 11 and coil 12 do not merge, and coil 11 and coil 12 are not electromagnetically coupled. Accordingly, inductances of respective coils 11, 12 are unchanged; impedance frequency characteristics of respective LC resonant circuits are maintained at what they should be; and resonant impedance(s) is/are not lowered.

Abstract: The pin pitches on the respective edges of a plurality of selectively mounted semiconductor devices match one another, and the distances between the edges differ from one another. Shared lands are arranged so as to correspond to contact pins disposed on one edge of the respective semiconductor devices. Accordingly, selectively mounting a plurality of types of semiconductor devices onto a printed circuit board is achieved while saving space.

Abstract: An LNB (low noise block down converter) that can have a plurality of receivers connected includes a conversion unit receiving a plurality of types of polarized wave signals transmitted from each of a plurality of satellites to convert the plurality of polarized wave signals into a plurality of intermediate frequency signals, an amplify switch connected to the conversion unit to receive the plurality of intermediate frequency signals as inputs, and having a plurality of outputs connected to a plurality of output ports, respectively, determining a status according to a select signal and providing an amplified intermediate frequency signal, and a first control unit receiving digital serial data to select a satellite from an external source via an output port and providing a select signal according to the digital serial data.

Abstract: A satellite antenna switching apparatus has LNB ports to which LNBs are connected, receiver ports to which receivers that exchange signals with the LNBs are connected, cascade ports to which another switching apparatus is cascade-connected, and impedance circuits that function as means for detecting the signals exchanged between the LNBs and receivers. The impedance circuits provide impedances according to the connection states of the cascade ports, and are electrically disconnected from the signal paths when another switching apparatus is cascade-connected to the cascade ports. With this configuration, the satellite antenna switching apparatus suffers from less attenuation of the exchanged signals even in a cascade connection of a plurality of stages of switching apparatuses.

Abstract: The present invention is a low noise blockdown converter (LNB) capable of ensuring sharing of specific information between or among a plurality of microcomputers. In the event that receiver 15 is connected to I/O port 14c assigned to slave microcomputer 13, slave microcomputer 13 may receive inquiry or inquiries from receiver 15 for information specific to LNB 11. Upon receiving such inquiry or inquiries, slave microcomputer 13 may, by way of bus 16, request that master microcomputer 12 provide specific information. Upon receiving such request or requests, master microcomputer 12 may, by way of bus 16, provide slave microcomputer 13 with specific information stored in advance at master microcomputer 12. Slave microcomputer 13 may send this specific information from I/O port 14c to receiver 15.

Abstract: A high impedance circuit of the present invention includes an LC parallel resonance circuit for raising circuit impedance, and a diode, which is connected in parallel to the LC parallel resonance circuit, causing a loop current to flow back via the diode and an inductor in the LC parallel resonance circuit so that a counter electromotive force, due to a surge voltage, which occurs across the inductor is cancelled. A low noise block downconverter which includes a high impedance circuit having a high impedance prevents peripheral circuits from being destroyed by a counter electromotive force, due to a surge voltage, which occurs across the inductor. For this, a diode is provided to cause a loop current to flow back via the diode and the inductor so that the counter electromotive force is cancelled.