(19)

(11)

EP 0 630 536 A1

(12)

(43) Date of publication: 28.12.1994 Bulletin 1994/52 (21) Application number: 94904248.0 (22) Date of filing: 13.01.1994

(51) International Patent Classification (IPC):  H03F 1/ 02( . ) H03G 3/ 20( . ) H03F 3/ 30( . ) H03G 3/ 30( . ) (86) International application number: PCT/GB1994/000064 (87) International publication number: WO 1994/016493 (21.07.1994 Gazette 1994/17)

(84) Designated Contracting States: DE FR GB IT NL (30) Priority: 14.01.1993 GB 19930000669 (71) Applicant: MARSHALL AMPLIFICATION PLC Milton Keynes MK1 1DQ (GB)	(72) Inventor: KEIR, Bruce Buckinghamshire MK17 0LU (GB) (74) Representative: Garratt, Peter Douglas, et al  Mathys & Squire 100 Grays Inn Road London WC1X 8AL London WC1X 8AL (GB)