公开(公告)号：US4402089A

公开(公告)日：1983-08-30

申请号：US302853

申请日：1981-09-16

申请人： Stanley P. Knight ,  John G. N. Henderson

发明人： Stanley P. Knight ,  John G. N. Henderson

IPC分类号： H04N5/44 ,  H03J3/28 ,  H03J5/02 ,  H03J5/24 ,  H04N5/50 ,  H04B1/26

CPC分类号： H03J3/28 ,  H03J5/0263

摘要： A television (TV) receiver tuning system for selecting one of a plurality of receivable TV channels comprises a frequency selective radio frequency device including trimming elements for receiving TV signals, a local oscillator controlled by a first control signal and a mixer in which the TV signals and the local oscillator signal are heterodyned to develop an intermediate frequency signal. A first control device develops the first control signal in response to the selection of a TV channel to control the local oscillator frequency so that the mixer shifts the selected TV channel signal to the IF frequency. A second control device including a PROM trims the frequency selectivity of the RF device using its trimming elements unaffected by selection of the TV channel whereby mechanical alignment of the TV tuning system can be avoided. In other aspects of the invention, the second control device develops signals for adjusting tunable circuits in the IF amplifier, for adjusting the tracking of the local oscillator frequency in relation to its control signal, and, in a double-conversion tuner, for adjusting the frequency of a second local oscillator.

摘要翻译： 用于选择多个可接收TV频道中的一个的电视（TV）接收机调谐系统包括：频率选择性射频设备，包括用于接收TV信号的修整元件，由第一控制信号控制的本地振荡器和其中TV信号 并且本地振荡器信号被外差以产生中频信号。 第一控制装置响应于选择TV信道来开发第一控制信号以控制本地振荡器频率，使得混频器将所选择的TV信道信号移位到IF频率。 包括PROM的第二控制装置使用其修整元件修改RF装置的频率选择性，而不受TV选择的影响，从而可以避免TV调谐系统的机械对准。 在本发明的其他方面，第二控制装置产生用于调整IF放大器中的可调谐电路的信号，用于相对于其控制信号调整本地振荡器频率的跟踪，并且在双转换调谐器中，用于调整 第二本地振荡器的频率。

公开(公告)号：US4405946A

公开(公告)日：1983-09-20

申请号：US348675

申请日：1982-02-16

申请人： Stanley P. Knight

发明人： Stanley P. Knight

IPC分类号： H04N5/445 ,  H04N5/775 ,  H04N21/41 ,  H04N21/488 ,  H04N5/50

CPC分类号： H04N21/488 ,  H04N21/4104 ,  H04N5/44513 ,  H04N5/775

摘要： In a signal converting apparatus such as one including demodulation and remodulation apparatus for converting RF cable carriers to RF carriers having frequencies corresponding to broadcast frequencies, a character generator is coupled to the tuning selector to generate characters representative of the channel number of the selected cable carrier. The character representative signals are combined with the demodulated base-band signals before remodulation. As a result, the television receiver coupled to the cable converter will produce an on-screen display of the channel number of the selected cable channel. Similar apparatus may be employed to identify a video cassette recorder or video disc player as the source of television signals on the screen of a television receiver.

摘要翻译： 在诸如包括用于将RF电缆载波转换成具有与广播频率相对应的频率的RF载波的解调和再调制装置的信号转换装置中，字符发生器耦合到调谐选择器以产生表示所选电缆载波的信道号的字符 。 字符代表信号与再调制之前的解调基带信号组合。 结果，耦合到电缆转换器的电视接收机将产生所选择的电缆信道的频道号的屏幕显示。 可以采用类似的装置来识别作为电视接收机的屏幕上的电视信号源的录像机或视频盘播放机。