Channel selection for a television receiver having low-gain high frequency RF-IF section
US4162452A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 5, 1977 |
| Grant date | Jul 24, 1979 |
| Priority date | — |
| Expiry date | Jul 5, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B5/362
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A channel selector for a television receiver having a low gain, high-frequency radio frequency-intermediate frequency section as combined with a relatively high-gain, lower intermediate frequency in the intermediate frequency section to reduce noise, such as intermodulation distortion and cross-modulation distortion. The channel selector comprises a frequency spectrum filter in the RF section, a mixer which preferably includes a metal semiconductor field effect transistor, i.e. MESFET, and a channel selecting filter. The frequency spectrum filter is coupled to the antenna of the television receiver and filters a frequency spectrum of radio frequency signals as received from the antenna, such as a plurality of television channels. The mixer has an input coupled to the frequency spectrum filter and frequency shifts selected channels of the frequency spectrum to a predetermined relatively high intermediate frequency. The RF section has a low gain RF amplifier connected between the frequency spectrum filter and the mixer or may have no RF amplifier at all. The channel selecting filter has an input coupled to the mixer and filters the selected channel at the predetermined intermediate f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.