Video tape recording/reproducing apparatus having an auto tracking function
US4489352A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1982 |
| Grant date | Dec 18, 1984 |
| Priority date | — |
| Expiry date | Apr 13, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/592
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal recording/reproducing apparatus includes a first set of rotary heads mounted on a rotary disk and a second set of rotary heads mounted on head actuators which are also mounted on the rotary disk. The apparatus has two reproduction modes. A magnetic tape in the first reproduction mode is driven at a speed equal to the speed used in a recording mode. The magnetic tape in the second reproduction mode is driven at a speed which is different from the speed used in the recording mode. The apparatus has a negative feedback loop which detects the reproduced signal level of the second set of rotary heads and drives the head actuators in order to increase the reproduced signal level of the second set of rotary heads. In the first reproduction mode, the negative feedback loop is intermittently closed. At the period of time when the negative feedback loop is open, the negative feedback loop holds the value of its output signal to that of the last time period when the negative feedback loop was closed, and, in addition, the head actuator is not driven when the feedback loop is open. At a transitional period when the apparatus switches from the first reproduction mode to the secon…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.