Abstract: Solely lightwaves required to be wavelength converted are filtered out from the input broadband WDM lightwaves and are wavelength converted by use of FWM. Not only the broadband simultaneous wavelength conversion that is studied by many researchers, but also more flexible, sub-band wavelength conversion is realized. Frequency interval of the input WDM lightwaves is broadened or reduced in comparison of the frequency interval of the WDM lightwaves inputted to the wavelength converter. The frequency interval variation techniques using the wavelength converter, it can be realized to transfer from a transmission lines less influenced by inter-channel crosstalk due to FWM to the different transmission lines strongly influenced by inter-channel crosstalk due to FWM, and vice versa.

Abstract: A surface mount self-induction component comprises a drum core having a winding core around which a winding is to be wound, and a pair of flanges which are opposedly placed at ends of the winding core, respectively, a plate core which elongates above the pair of flanges, and electrodes which are respectively formed on side faces of the opposed flanges, the side faces being parallel with an axial direction of the winding core, a diameter of the winding being collapsed by pressurizing or heating, thereby connecting terminals of the winding to said electrodes.

Abstract: A BALUN transformer core material contains a Z-type hexagonal system ferrite having an in-plane anisotropy and a high magnetic permeability and such a high resonance frequency as to be in excess of a Snake's limiting line, and therefore, in the BALUN transformer core material, the frequency properties of the magnetic permeability are extremely good. A BALUN transformer core obtained by pressing and sintering this BALUN transformer core material has a high initial magnetic permeability and specific resistance. Moreover, a BALUN transformer obtained by applying a winding to the BALUN transformer core is provided with superior properties which are not poorer as compared with a BALUN transformer constituted of a conventional spinel ferrite, and it is a BALUN transformer having high properties which can be used in a high-frequency band of 300 MHz or more.

Abstract: There is disclosed a BALUN transformer core material which has no magnetic permeability, contains a non-magnetic material and is not influenced by the frequency property of the magnetic permeability even in a high-frequency band. A BALUN transformer core which is obtained by pressing and sintering the BALUN transformer core material has no magnetic permeability and has a high specific resistance. A BALUN transformer which is obtained by applying a winding to the BALUN transformer core is a high-property BALUN transformer which can be operated in a high-frequency band of 600 MHz or more.

Abstract: A BALUN transformer core material contains a Z-type hexagonal system ferrite having an in-plane anisotropy and a high magnetic permeability and such a high resonance frequency as to be in excess of a Snake's limiting line, and therefore, in the BALUN transformer core material, the frequency properties of the magnetic permeability are extremely good. A BALUN transformer core obtained by pressing and sintering this BALUN transformer core material has a high initial magnetic permeability and specific resistance. Moreover, a BALUN transformer obtained by applying a winding to the BALUN transformer core is provided with superior properties which are not poorer as compared with a BALUN transformer constituted of a conventional spinel ferrite, and it is a BALUN transformer having high properties which can be used in a high-frequency band of 300 MHz or more.

Abstract: A wirewound balun transformer for planar packaging comprising a flanged core which has end flanges at both ends, at least one center flange, and two or more winding recesses, a flat core held in parallel with the flanged core, and windings coiled around the winding recesses, characterized in that one side face of the center flange is not flush with but is formed behind the plane that connects one side faces on the same side of the end flanges, each of the end flanges of the flanged core has an opposing pair of electrodes formed on both side faces, and the center flange has a single electrode formed on the opposite side face.

Abstract: A coil component comprises a pot core having through holes formed in the bottom, a coil so shaped as to fit in the pot core, and a cover core joined to the rim of the pot core. The coil has terminals inserted in the through holes to such an extent that their lower ends do not protrude beyond the bottom. The bottom has membrane external electrodes formed on its outersurface and connected with the terminals.

Abstract: A covered arc welding electrode includes a steel core wire and a flux which is applied to the outside periphery of said steel core wire. The welding electrode can form a superior crack-resisting weld zone even if fluctuating stresses are continually applied to a base metal while the base metal is welded. The flux includes 40 to 60% metal carbonate, 10 to 25% metal fluoride and 4 to 25 metal oxide by weight. The flux comprises 24 to 32% of the total weight of said electrode. The composition of the welding electrode includes 0.005 to 0.05% carbon, 0.1 to 1.1% silicon, 1.5 to 2.5% manganese, not more than 0.007% sulfur and not more than 0.25% nickel by weight and the manganese/sulfur ratio is more than or equal to 350 to 1. In addition, the welding electrode can include 0.01 to 0.10% rare earth metal by weight. In which case, the Mn content may be 1.0 to 2.5% by weight and the manganese/sulfur ratio may be more than or equal to 270 to 1.