Data slicer circuit for separating and recovering digital teletext signals
US4656513A · kind A · utility
7Cited by
1References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1984 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Nov 30, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/0882
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A data slicer circuit for separating and recovering digital teletext signals from a demodulated composite color signal derives the slicing level by using a framing code detector and a gating pulse having an active phase during horizontal and color sync pulses. By an adder or a multiplier, a start value is formed at the beginning of each picture line. A square wave reference signal is formed which is subtracted from the start value containing composite color signal. From the difference signal, a digital automatic control system forms the slicing level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.