Patent · US Expired

Player for digitally recorded music

US4351213A · kind A · utility

0Cited by
5References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 20, 1979
Grant dateSep 28, 1982
Priority date
Expiry dateAug 20, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S84/10
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

An apparatus (10) for transforming digital data stored in a memory (18) into sounds is disclosed. The apparatus includes an oscillator (12) which drives an address selector (14). The address selector drives the memory. A note generator (20) generates an analog electrical signal responsive to the memory, and a speaker with its associated amplifier stages (22) produces sounds corresponding to the analog electrical signal. A preferred arrangement of the note generator includes an inverting amplifier which can simply be a logic gate (44) and a plurality of resistors (50) selected by switches (56) in feedback relationship with the amplifier. A preferred arrangement includes a duty cycle selector (80) to produce harmonics of the fundamental frequency of the analog electrical signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.