GB1281170A - Automatic visual indicator and transposing device for organ, electronic organ and pianoforte - Google Patents

Abstract

1281170 Note indicators KEY DEVELOPMENTS Ltd 22 Oct 1969 [17 April 1969] 19610/69 Heading G5X An indicator comprises a translucent panel on which the lines of the staff are marked and behind which indicator lamps are positioned (Fig. 2, not shown). The associated circuit, so far as concerns only the notes C to E, is as shown. A switch 59 energizes one of the bus-bars 51-57, each corresponding to a selected key, and causes key signature lamps such as 66, 67 to display sharps or flats in the required positions on the staff. Operation of notes of a keyboard closes switches 42-46 and, in the ease of the notes C, D, E for example, causes lamps 48-50 to indicate notes in the corresponding position in the lines and spaces of the staff, at least when the key of C is selected on the switch 59. If a key, say D or A, is selected which includes say C sharp in the signature the lamp 50 will be lit to indicate the note C by closing the switch 45 of the note C sharp. If the switch 46 of the note C is closed the lamp 50 will be lit and also a lamp 64 indicating an accidental natural. Other lamps 60-63 indicate accidental sharps, flats and naturals as appropriate to particular notes in particular selected keys. A switch 82 causes a relay 81 to be energized so that, when a key is selected having a signature of flats, the enharmonic note D sharp/E flat is displayed as E flat i.e. closure of the switch 43 lights the lamp 48 and the lamp 60 also if E flat does not appear in the key signature. In the keys having sharp signatures the relay 81 is normally de-energized and the same note is then displayed as D sharp, unless a switch 77 is closed when the key of C or G has been selected. The note is then displayed as E flat. The switch 77 enables the automatic selection of E flat or D sharp to be over-ridden in the case of a minor key, such as E minor, which has the same signature as a major key such as G major. The keyboard for operating the device may be the keyboard of an electrophonic instrument and either the visual indication or the sound output may be switched off.