Patent · US Expired

Display device for displaying audio signal levels and characters

US4492917A · kind A · utility

8Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1982
Grant dateJan 8, 1985
Priority date
Expiry dateAug 30, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R13/22
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A level display device for audio signal comprises a plurality of bandpass filters having filtering bands of respectively different center frequencies, for band-dividing and filtering an input signal supplied thereto through an input terminal, a level indication signal producing circuit for converting the input signal into a signal in synchronism with a horizontal synchronizing signal of a video signal and having a pulse width in accordance with the level of the horizontal synchronizing signal, and serially obtaining the converted signal in sychronism with a vertical synchronizing signal of the video signal by successive time-division carried out during a vertical scanning period, a character indication signal producing circuit stored with information signals for displaying characters and the like, for serially obtaining a character indication signal in synchronism with a synchronizing signal of the video signal, and a video signal composing circuit driven by the video signal, for obtaining a video signal by composing an output of the level indication signal producing circuit and an output of the character indication signal producing circuit. The level display device composes and di…

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