Rotary recording medium having track turns recorded with digital signal and track turns recorded with analog signal
US4660099A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 1984 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | May 11, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A rotary recording medium has information signals recorded on a spiral or concentric tracks formed thereon as variations in geometrical configuration. The tracks comprise a mixture of digital recorded tracks which are recorded with a first modulated signal and analog recorded tracks which are recorded with a second modulated signal. The first modulated signal is a digital signal which has been time-sequentially multiplexed in terms of blocks at a transmission frequency of 44.1 kHz or a frequency extremely close to 44.1 kHz and has then been subjected to a modulation, where each of the blocks are constituted by a synchronizing signal, error correcting codes, and an error detecting code, which are added to a plurality of channels of digital data which are digitally modulated information signals. The second modulated signal is an analog modulated analog information signal at least including a composite video signal. A number of blocks recorded in one track turn of the digital recorded tracks is approximately equal to a product of the transmission frequency and a duration of one revolution of the rotary recording medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.