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1.发明授权Television tuning system with provisions for receiving RF carrier at nonstandard frequency 失效电视调谐系统，用于以非标准频率接收RF载波
公开(公告)号：US4031549A
公开(公告)日：1977-06-21
申请号：US688521
申请日：1976-05-21
CPC分类号： H03J7/065 , H03J5/0272 , Y10S331/02
摘要： A tuning system for a television receiver includes a phase locked loop for tuning a local oscillator to the nominal local oscillator frequencies required to tune the receiver to RF carriers at standard broadcast frequencies allocated to the various channels a viewer may select. The tuning system also includes an automatic fine tuning (AFT) frequency discriminator for tuning the local oscillator to minimize any deviation between the frequency of an actual picture carrier and the nominal picture carrier frequency. If the receiver is coupled to a television distribution system which provides RF carriers having nonstandard frequencies arbitrarily near respective ones of the standard broadcast frequencies, when the phase locked loop has achieved lock at a nominal frequency, a mode control unit selectively couples the discriminator and a frequency drift control circuit to the local oscillator. If the frequency of the local oscillator drifts more than a predetermined offset from the frequency synthesized under phase locked loop control because no carrier has been detected by the discriminator, discriminator and drift control are terminated so that the receiver will not be tuned to an undesired carrier such as, for example, the lower adjacent channel sound carrier, and phase locked loop control is reinitiated to synthesize a local oscillator signal having a frequency different from the frequency of the originally synthesized local oscillator signal by a predetermined amount. After the phase locked loop is locked at the new frequency, discriminator control is again initiated.
摘要翻译： 用于电视接收机的调谐系统包括用于将本地振荡器调谐到分配给观众可以选择的各种频道的标准广播频率将接收机调谐到RF载波所需的标称本地振荡器频率的锁相环。 调谐系统还包括用于调谐本地振荡器的自动微调（AFT）鉴频器，以最小化实际图像载波的频率与标称图像载波频率之间的任何偏差。 如果接收机耦合到电视分配系统，该电视分配系统提供具有任意接近标准广播频率的相应标准广播频率的非标准频率的RF载波，则当锁相环已经达到标称频率的锁定时，模式控制单元选择性地将鉴别器和 频率漂移控制电路到本地振荡器。 如果本地振荡器的频率漂移超过在锁相环控制下合成的频率的预定偏移，因为鉴别器没有检测到载波，则终止鉴频器和漂移控制，使得接收机不会被调谐到不需要的载波 例如下相邻声道声音载波，并且重新启动锁相环控制，以将具有与原始合成的本地振荡器信号的频率不同的频率的本地振荡器信号合成预定量。 锁相环锁定在新频率之后，再次启动鉴频器控制。
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公开(公告)号：US4077008A
公开(公告)日：1978-02-28
申请号：US733673
申请日：1976-10-18
申请人： Robert Morgan Rast , Juri Tults
发明人： Robert Morgan Rast , Juri Tults
CPC分类号： H03J7/285 , H03J5/0272 , Y10S331/02
摘要： A tuning system for a television receiver includes a first phase locked loop configuration for controlling the frequency of the receiver's local oscillator signal in accordance with the number of the channel presently being tuned and a second phase locked loop configuration for controlling the frequency of the local oscillator signal to reduce any frequency deviation between the receiver's IF picture carrier and 45.75 MHz corresponding to a frequency offset between the associated RF carrier and the standard RF carrier frequency for the channel being presently tuned due to the frequency translation provided by a television distribution system. The tuning system includes control units for automatically changing the channel number and selectively enabling the operation of the first and second phase locked loop configuration in accordance with a tuning algorithm so that active channels may be automatically located and tuned while preventing the receiver from being erroneously tuned to undesirable signals.
摘要翻译： 用于电视接收机的调谐系统包括第一锁相环配置，用于根据目前调谐的信道的数目控制接收机的本地振荡器信号的频率，以及用于控制本地振荡器的频率的第二锁相环配置 信号，以减少由于由电视分配系统提供的频率转换而正在调谐的信道的接收机的IF图像载波与45.75MHz之间的频率偏移相对应的相关RF载波与标准RF载波频率之间的频率偏移。 调谐系统包括用于根据调谐算法自动改变通道号并选择性地启用第一和第二锁相环配置的操作的控制单元，使得可以自动定位和调谐有源通道，同时防止接收器被错误调谐 到不良信号。
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公开(公告)号：US4078212A
公开(公告)日：1978-03-07
申请号：US758294
申请日：1977-01-10
申请人： Robert Morgan Rast
发明人： Robert Morgan Rast
CPC分类号： H03J5/0272 , H03L7/199 , Y10S331/02
摘要： Television tuning apparatus includes a first phase locked loop configuration for tuning a local oscillator to a nominal frequency appropriate for converting a standard radio frequency carrier allocated to a selected channel to a predetermined intermediate frequency (e.g., 45.75 MHz) and a second phase locked loop configuration for tuning the local oscillator to minimize any deviation between the actual frequency of the I.F. picture carrier and its nominal frequency which may occur, for example, because the receiver is coupled to a distribution system utilizing frequency conversion apparatus which provides nonstandard radio frequency carriers arbitrarily near respective standard frequency carriers. The two phase locked loop configurations include common elements and control apparatus to selectively initiate the operation of one loop while inhibiting the operation of the other in accordance with a predetermined tuning algorithm.
摘要翻译： 电视调谐装置包括第一锁相环配置，用于将本地振荡器调谐到适于将分配给所选信道的标准射频载波转换为预定中频（例如，45.75MHz）的标称频率和第二锁相环配置 用于调谐本地振荡器以最小化IF的实际频率之间的任何偏差 图像载体及其标称频率，例如，因为接收机耦合到使用频率转换装置的分配系统，该装置在各自的标准频率载波附近任意地提供非标准射频载波。 两个锁相环配置包括公共元件和控制装置，用于选择性地启动一个环路的操作，同时根据预定的调谐算法阻止另一个的操作。
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公开(公告)号：US4009439A
公开(公告)日：1977-02-22
申请号：US662097
申请日：1976-02-27
申请人： Robert Morgan Rast
发明人： Robert Morgan Rast
CPC分类号： H03J5/0272
摘要： A phase locked loop type of television tuning apparatus includes an apparatus for dividing the frequency of a local oscillator signal by a number equal to the frequency of the local oscillator signal, in MHz, corresponding to the presently selected channel. The divider forms an output signal including first and second portions having durations respectively equal to first and second predetermined numbers of periods of the local oscillator signal. The first number is related to the number of the selected channel. The second number is related to the frequency band in which the selected channel resides. To determine the frequency band of the selected channels, band traversed signals are generated whenever the number of periods of the local oscillator signal generated since beginning of the first portion corresponds to the first channel in a band. When a new band traversed signal is generated, the previous band traversed signal is terminated. The band traversed signal remaining at the end of the first portion determines the band in which the selected channel resides.
摘要翻译： 锁相环类型的电视调谐装置包括用于将本地振荡器信号的频率除以等于本地振荡器信号的频率的数值（MHz）的装置，其对应于当前选择的信道。 分频器形成输出信号，该输出信号包括具有分别等于本地振荡器信号的第一和第二预定数量周期的持续时间的第一和第二部分。 第一个数字与所选频道的号码有关。 第二个数字与所选频道所在的频带有关。 为了确定所选择的信道的频带，每当从第一部分开始产生的本地振荡器信号的周期数对应于频带中的第一信道时，产生频带遍历信号。 当产生新的频带遍历信号时，先前的频带遍历信号被终止。 穿过第一部分结束处剩余的信号的频带确定所选频道驻留的频带。
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公开(公告)号：US4109283A
公开(公告)日：1978-08-22
申请号：US688588
申请日：1976-05-21
申请人： Robert Morgan Rast
发明人： Robert Morgan Rast
CPC分类号： H03J7/065 , H03J5/0272 , Y10S331/02
摘要： A tuning system for a television receiver includes a local oscillator which is controlled first by a phase lock loop arrangement and then by an AFT discriminator arrangement for tuning the receiver to non-standard as well as standard frequency carriers. The phase lock loop arrangement includes a programmable divider for dividing the local oscillator frequency by a programmable factor corresponding to the presently selected channel. When the local oscillator is being controlled by the AFT discriminator arrangement, the count accumulated by the programmable divider during a reference interval determines how far the local oscillator frequency has drifted from its nominal value. If a predetermined frequency offset has been exceeded, control is returned to phase lock loop control and the programmable factor is incrementally changed.
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