Patent GB-1139992-A (GB)
Title: Phonograph record selection control system
IPC: G11B17/22
Filed: 1966-09-20
Abstract: 1,139,992. Magnetic core store apparatus. SEEBURG CORP. 20 Sept., 1966 [8 April, 1966], No. 42040/66. Heading H3B. The selection of gramophone records for reproduction is controlled for either programmed sequential play or individual selection play. As described, the system includes magnetic core matrices to control the selection. A first magnetic core matrix has row and column conductors A to K and 1 to 0, one core being associated with each side of a record and being selected by coincident energization of a row and a column conductor. A pulse source is connected by way of a first selection switch 29 to a row conductor, the other ends of the row conductors being connected in common by way of a second selection switch 31 to a row line. As a selector member 107 subsequently passes each record a pulse is supplied from a read pulse source to a corresponding core. When the selector reaches a selected record the read pulse switches the corresponding core back to a reference state and the resulting output pulse causes the selector to stop, select the record and cause it to be played. A second core arrangement, also having one core for each selection, has conductors A<SP>1</SP> to K<SP>1</SP> associated with groups of cores. The groups are combined in larger groups, e.g. A<SP>1</SP> to C<SP>1</SP>, D<SP>1</SP> to G<SP>1</SP> and H<SP>1</SP> to K<SP>1</SP>, as shown, by means of selection switches 99,101 The larger groups each define a separate programme. By means of a push-button selection arrangement including switches 47, 49, 63, 65, 79, 81 each of these programmes can be selected individually. The cores of the selected programme are thereupon switched by means of pulses from source 43. The selector 107 will then select the records of the selected programme sequentially, using a similar read out arrangement to the individual selection matrix. A further push-button switch is provided for operating a programme timing arrangement so that a programme is selected automatically. Read-out circuitry (Fig. 2). Read-out pulses are supplied from line 115 to either the individual selection matrix 4 or the programme selection arrangement 5 by way of relay 119. The system normally proceeds through a programme until an individual selection is made. This causes relay 119 to change over so that an individual selection always takes priority over a preselected programme. After playing the individual selection the machine returns to the programme mode and takes up the previous programme where it left off. If a second programme is selected before a previous programme is finished the uncompleted programme is completed after the second programme is finished. The switch arrangement 148 prevents the unplayed part of the first programme being erased during playing of the second programme. The selector 107 is associated with two cam switches 177, 179 which run on two cam tracks each of which has regions corresponding to each of the selection groups A<SP>1</SP> to K<SP>1</SP>. Cam plates are placed on one track in the positions corresponding to the selection groups forming the second programme and on the other track in the positions corresponding to the selection groups forming the third programme. Cam switches 177, 179 take up the positions shown on the right in Fig. 2, when neither cam switch is on a cam plate, the positions in the centre when 179 is on a cam plate 199 in the first track and the positions shown on the left when 177 is on a cam plate 197 in the second track. If the first programme has been selected read out pulses are produced from source 109 until group D<SP>1</SP> is reach. In this position switch 179 is changed over by cam plate 199 and point 151 is earthed, disabling the pulse source and preventing group D<SP>1</SP> from being selected. Similar conditions exist for positions E<SP>1</SP> to G<SP>1</SP>. In position H<SP>1</SP> switch 179 is restored but switch 181 is switched over so that point 151 is still earthed. If programme 2 is selected only groups D<SP>1</SP> to G<SP>1</SP> are read out, and for programme 3 groups H<SP>1</SP> to K<SP>1</SP> are selected. Additional cam plates may be added to either track to suppress one group of records from a programme, e.g. group B<SP>1</SP> is omitted from programme 1 if a cam plate is placed in position B<SP>1</SP> in either track.