Apparatus and method for stereo television sound
US4646150A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1986 |
| Grant date | Feb 24, 1987 |
| Priority date | — |
| Expiry date | Jan 3, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/607
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method are provided for receiving and reproducing stereo television sound. A transmitted television signal is received that contains a first component comprising the sum of first and second stereophonically related audio signals and a second component comprising the difference between the first and second stereophonically related audio signals. The first and second components are converted to produce a first sound carrier centered at a first intermediate frequency and a second sound carrier centered at a second intermediate frequency. The first component is detected from the first sound carrier at the first intermediate frequency. The second component is detected from the second sound carrier at the second intermediate frequency. The detected first and second components are combined to produce a left channel audio output and a right channel audio output. By using a standard intercarrier detector for the first (L+R) component and an independent FM detector for the second (L-R) component, distortion caused by interfering harmonics of the television horizontal line frequency with vertical scan frequency sidebands falling within the (L-R) subchannel is prevented. A sec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.