SECAM Subcarrier generator
US4084177A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1977 |
| Grant date | Apr 11, 1978 |
| Priority date | — |
| Expiry date | Mar 23, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/45
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A reference signal generator is provided for generating the two subcarrier reference frequencies for the SECAM television system. A master oscillator generates the first subcarrier reference frequency which is coupled to a divider for obtaining the horizontal line rate. The horizontal line rate is multiplied and coupled to a mixer, where it is mixed with the first subcarrier to obtain sum and difference frequencies. A crystal filter coupled to the mixer extracts the second subcarrier, which is locked in frequency and phase relationship to the first subcarrier. The signal generator also contains provisions for synchronizing the subcarriers to an external horizontal system reference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.