Abstract: A composite bead element comprises a chip-like magnetic body in a shape of a nearly rectangular parellelepiped in which a recess is provided, at least one feed-through holes formed in said body and an electronic component inserted in said recess. Bead inductors are formed by conductors provided in said feed-through holes, and said electronic component and said conductors are connected by predetermined conductors on a surface of said body.

Abstract: A chip-like inductance element including a magnetic sleeve having a feed-through hole between end surfaces thereof and electrode layers fromed on the end surfaces, and a drum-like magnetic bobbin fitted in the hole such that a gap is formed between the bobbin and sleeve and including end flanges and a central cylindrical region for a coil winding therearound, comprises solder layers for connecting terminals of the coil winding to the electrode layers, and insulating layers covering the solder layers and the end surfaces of the drum-like magnetic bobbin and being filled in the gap.

Abstract: An impedance element having a longitudinal current path surrounded by ferromagnetic material is implemented by the combination of a single rectangular ferrite chip, some through holes provided through said chip, through hole conductors plated on surface of said through holes, a pair of terminal conductors plated at ends of said chip, a surface conductive pattern deposited on front and back surfaces of said ferrite chip so that said through hole conductors are connected in series to one another between said terminal conductors, and insulation layers covering said surface conductors and said through hole conductors on both front and back surfaces of said ferrite chip. The present impedance element is small in size with relatively large impedance, and is applicable for instance to a high frequency noise filter.

Abstract: A cathodic protection electrode is mounted in an iron bushing by way of a ring of alumina or forsterite, the bushing being mounted in a glass-lined metallic vessel, such as a water heater. The electrode comprises a solid solution of MFe.sub.2 O.sub.4 (wherein M is at least one metal selected from the group consisting of Mn, Ni, Co, Mg, Cu and Zn) of 0.15 to 87.1 mol%, and Fe.sub.3 O.sub.4 of 99.85 to 12.9 mol%.