1288/91 - Item 7: Apparatus, known as ‘chromatic tuners’, with the following characteristics: several tuning-methods and two transposition-functions adapted to a range of musical instruments; microphone, quartz oscillator, pointer- type frequency meter and light-emitting diodes whether or not with a loudspeaker; seven-octave tuning range (from 32,7 to 395,1 Hz). - The Trade Hub