Patent · US Expired

Apparatus for recording and/or reproducing video and audio signals

US4580174A · kind A · utility

21Cited by
1References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 18, 1983
Grant dateApr 1, 1986
Priority date
Expiry dateNov 18, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/8355
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video and audio signal recording apparatus includes a first frequency modulator in which a first audio signal to be recorded that may represent a stereophonic left channel modulates a first carrier to produce a first FM audio signal, and a first frequency convertor converts the carrier frequency of the first FM audio signal to a different carrier frequency higher than the first carrier frequency to form a second FM audio signal. A second frequency modulator modulates a second audio signal to be recorded that may represent a stereophonic right channel to produce a third FM audio signal, and a second frequency converter converts the third FM audio signal into a fourth FM audio signal having a carrier frequency that is higher than any of the other FM audio signals so modulated. The first and third FM audio signals are mixed to form a first mixed audio signal and the second and fourth FM audio signals are mixed to form a second mixed audio signal, which are both combined in a mixing circuit with a composite color video signal to form first and second mixed audio and video signals which are fed to first and second magnetic recording heads, respectively. Reproducing apparatus reproduce…

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