Patent · US Expired

Level display device for audio signal

US4577188A · kind A · utility

9Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1982
Grant dateMar 18, 1986
Priority date
Expiry dateAug 30, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R13/408
  • 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 pulse width converter provided in correspondence with respective bandpass filters, for converting the input signal into a signal in synchronism with a vertical synchronizing signal of a video signal and having a pulse width in accordance with the level of the vertical synchronizing signal, a level indication signal producing circuit connected with outputs of the pulse width converter in parallel, for serially producing the converted pulse signal in synchronism with a horizontal synchronizing signal by successively time-dividing the converted pulse signal during a horizontal 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 …

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