Speed and phase control system
US4086520A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1976 |
| Grant date | Apr 25, 1978 |
| Priority date | — |
| Expiry date | Feb 19, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/183
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In an apparatus having at least one rotary head for reproducing video signals recorded in successive parallel tracks extending obliquely across a tape which is advanced longitudinally and also has control signals recorded therein in predetermined positional relationship to the respective record tracks to be reproduced by a fixed transducer or head with a repetition rate that is dependent on the speed of advancement of the tape: a speed and phase control system for the rotary head or heads has a rotational speed detector for producing pulse signals representative of the rotational position of each rotary head and having a repetition rate that is a function of the rotational speed of the rotary head; a phase comparator for producing a phase responsive signal having a voltage level that is varied in response to changes in the relative timing of the reproduced control signals and the pulse signals; a digital device for producing a speed responsive signal having a voltage level that generally corresponds to the repetition rate of the pulse signals, but which is varied in response to changes in the repetition rate of the pulse signals only when such changes occur without corresponding ch…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.