System for recording and/or reproducing an audio signal which has been converted into a digital signal
US4246615A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1978 |
| Grant date | Jan 20, 1981 |
| Priority date | — |
| Expiry date | Dec 15, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1813
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A composite video signal recording and reproducing system also records and reproduces an audio signal after their conversion into a digital signal. The recording system converts an input analog audio signal into a digital signal and generates a synchronizing signal corresponding to a synchronizing signal of the composite video signal. There is a time-axis compression of the converted digital signal so that they do not exist in the period corresponding to the synchronizing signal. A level-setter sets the level of the digital signal which has been compressed at a value which is lower than the white peak level of the composite video signal. A mixer mixes the level set digital signal and the generated synchronizing signal, to obtain a composite digital signal. The composite digital signal is supplied to the recording and/or reproducing apparatus and recorded on a recording medium. The level-setter sets the amplitude of the digital signal at a magnitude such that the overshoots and undershoots occurring as a result of the passage of the digital signal through a pre-emphasis circuit of the recording and/or reproducing apparatus will not be clipped by a clipping circuit of the recording a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.