GB531808A - Improvements in or relating to supporting arms of pick-ups and sound recorders - Google Patents

Abstract

531,808. Gramophones. PHILIPS LAMPS, Ltd. Aug. 2, 1939, No. 22470. Convention date, Aug. 5, 1938. [Class 40 (ii)] The supporting arm of a pick-up or recorder is constituted by the electrical conductors, of which at least one is stiff and at least one other is frictionally coupled along its length to a stiff one to introduce the necessary damping. As shown in Fig. 1, a stiff conductor 19 of U-shaped cross-section is attached to the pick-up 10 and is pivotally mounted at 17, and a flexible insulated conductor 20 lies in the channel of the conductor 19. In a modification, an insulated conductor lies inside a stiff tubular conductor attached at one end to the pick-up and mounted at the other end on a ball joint. The outside of the stiff tubular conductor may be lacquered to increase damping. In another modification, an inner tubular conductor is separated from an outer stiff tubular conductor by a spirally wound insulating thread. In another form, Fig. 3, a pick-up of the kind described in Specification 510,297, [Group XXXIX], is attached to two stiff conductors 29, 32 into which are fitted flexible conductors 30, 33 forming flexible joints at 31, 34 with the support 35.