(19)

(11)

EP 0 593 635 A1

(12)

(43) Date of publication: 27.04.1994 Bulletin 1994/17 (21) Application number: 92915388.0 (22) Date of filing: 13.07.1992

(51) International Patent Classification (IPC):  H01P 1/ 208( . ) (86) International application number: PCT/GB1992/001275 (87) International publication number: WO 1993/001625 (21.01.1993 Gazette 1993/03)

(84) Designated Contracting States: DE FR GB (30) Priority: 11.07.1991 GB 19910149708 (71) Applicant: FILTRONIC COMPONENTS LIMITED Charlestown Shipley West Yorkshire, BD17 7SW (GB)	(72) Inventor: SLEIGH, Philip, David 8 Moor Park Close Addingham West Yorkshire LS29 OQE (GB) (74) Representative: Gibson, Stewart Harry  URQUHART-DYKES & LORD, Three Trinity Court, 21-27 Newport Road Cardiff CF2 1AA Cardiff CF2 1AA (GB)