发明授权
- 专利标题: Double trapping of adjacent channel sound
- 专利标题(中): 双重捕获相邻通道声音
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申请号: US32025申请日: 1979-04-20
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公开(公告)号: US4263619A公开(公告)日: 1981-04-21
- 发明人: Gerald E. Theriault
- 申请人: Gerald E. Theriault
- 申请人地址: NY New York
- 专利权人: RCA Corporation
- 当前专利权人: RCA Corporation
- 当前专利权人地址: NY New York
- 主分类号: H03J3/08
- IPC分类号: H03J3/08 ; H04N5/44 ; H04N5/60
摘要:
A network is provided for attenuating the adjacent channel sound carrier signal in a television receiver. First and second trap circuits are serially coupled intermediate the R.F. mixer and the first I.F. amplifier. One of the trap circuits is tuned to a frequency in the vicinity of and above the nominal frequency of the adjacent channel sound carrier, and the other is tuned to a frequency in the vicinity of and below that of the adjacent channel sound carrier. The two trap circuits are mutually coupled to a degree necessary to produce a composite response curve exhibiting a substantially constant level of maximum attenuation in the vicinity of the nominal frequency location of the adjacent channel sound carrier. The trap circuits provide attenuation in excess of that required to eliminate adjacent channel sound carrier interference over a bandwidth sufficient to encompass expected carrier deviation due to frequency modulation, carrier mislocation, and trap mistuning.
公开/授权文献
- US6057561A Optical semiconductor element 公开/授权日:2000-05-02
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