GB352391A - Improvements in or relating to gramophones or similar sound-recording instruments - Google Patents

Abstract

352,391. Recording attachments for gramophones. KINGSTON, A. W., 9, Newman Street, Oxford Street, London. March 28, 1930, No. 9991. [Class 40 (ii).] A recording attachment for gramophones for recording local or broadcast sounds comprises a pivoted arm mounted to swing over the turntable and carrying a recording device and also a traversing device adapted to track a smooth spiral groove formed in the outer part of a disc applied to the turntable and supporting the record blank within the spiral groove, provision being made for supporting the traversing device out of action and adjusting a loading weight when the attachment is used for reproducing. As shown, an arm in two parts 12, 13 connected by joint 14 is mounted to swing on a vertical pivot on a bracket 15 and carries on its outer part 12 an electromagnetic recorder 16 adjustably held in a socket 18 and a weight 20. A spring blade 27 frictionally and adjustably pivoted to the weight 20 carries a pin 26 arranged to track a smooth spiral groove in a disc 23 resting over the turntable whereby the recorder 16 is traversed over the record blank 22 supported on a rubber mat 24 on the disc 23 whilst sound currents from a microphone or a wireless receiver are fed thereto. The spring blade 27 may be lifted and swung round on to a supporting pin 127 on the weight 20 when the apparatus is to be used for reproducing from a record, and the part 12 of the arm may be turned back on the joint 14 so that the socket 18 rests on a support 19 when the apparatus is not in use. The arm may be weighted by an adjustable weight on a horizontal bar with downturned end engaging a socket on the part 12 and arranged so that when the bar extends towards the support 15 the load is suitable for reproducing but is turned into the opposite direction to increase the loading effect for recording. For recording local sounds the recorder 16 is replaced by a recording sound-box with diaphragm and a soundreceiving horn is mounted on the other end of the socket 18. Specifications 785/02, [Class 40, Electric telegraphs &c.], 103,624, and 331,429, [both in Class 40 (ii), Phonographs &c.], are referred to.