Magnetic recording and reproducing device
US5414567A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 1990 |
| Grant date | May 9, 1995 |
| Priority date | — |
| Expiry date | Dec 11, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/802
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording method and apparatus which performs a quadrature phase shift keying operation on a digital information signal, superimposes a high frequency bias signal on the performed signal, records the resulting signal into a deep portion of a magnetic layer of a magnetic tape with a first rotational head, and records a video signal in a surface portion of the magnetic layer above a track formed by the former recording, with a second rotational head which is different in azimuth angle from the first rotational head, the frequency of the high frequency bias signal being set to a value which is about four times as high as the carrier frequency of the quadrature phase shift keyed digital information signal, thereby eliminating a 5th-order distortion component due to cross modulation of the high frequency bias signal and the carrier frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.