公开(公告)号：US4330792A

公开(公告)日：1982-05-18

申请号：US210839

申请日：1980-11-26

申请人： Saiprasad V. Naimpally

发明人： Saiprasad V. Naimpally

IPC分类号： H01F38/42 ,  H04N5/44 ,  H04N5/59 ,  H04N9/64 ,  H04N9/72 ,  H04N9/535

CPC分类号： H04N5/59

摘要： A circuit is disclosed for automatically blanking the kinescope of a color television receiver during channel changing intervals. The receiver also includes an automatic kinescope beam current limiter, plural kinescope driver stages, and a source of reference bias voltage to which video signals amplified by the kinescope driver stages are normally referenced, coupled in common to the plural kinescope driver stages. During channel changing intervals, the blanking circuit modifies the reference voltage with a given blanking response time so that the driver stages and kinescope are blanked. The blanking circuit exhibits an unblanking response time, slower than the blanking response time, for permitting the reference bias voltage to gradually return to a normal level after the channel change interval ends, at which time the driver stages and kinescope are unblanked and operate normally.

摘要翻译： 公开了一种用于在频道改变间隔期间自动消隐彩色电视接收机的显像管的电路。 接收机还包括自动显象管光束电流限制器，多个显像管驱动器级以及通常被引用由显象管驱动器级放大的视频信号的参考偏置电压源，共同耦合到多个显像管驱动器级。 在通道更换间隔期间，消隐电路以给定的消隐响应时间修改参考电压，使得驱动级和显像管被消隐。 消隐电路具有比消隐响应时间慢的非空白响应时间，用于在信道改变间隔结束之后允许参考偏置电压逐渐恢复到正常电平，此时驱动器级和显像管未被平坦化并且正常工作。

公开(公告)号：US4288811A

公开(公告)日：1981-09-08

申请号：US135926

申请日：1980-03-31

申请人： Saiprasad V. Naimpally

发明人： Saiprasad V. Naimpally

IPC分类号： H04N9/78 ,  H04N9/535

CPC分类号： H04N9/78

摘要： A composite filter in a color television receiver includes a bridged-T network and a chrominance bandpass filter for mutually separating the luminance and chrominance components of a color television signal. In the bridged-T network, first and second signal paths are coupled between an input source of television signals and an output, the second path including a first reactance. A third signal path including a second reactance is coupled between an intermediate point in the second path and the input of the bandpass filter. The first and second reactances are tuned to the frequency of the color subcarrier signal of the chrominance component. A fourth, resistive signal path is coupled between the input of the bandpass filter and a reference potential. The four signal paths form a first filter for attenuating the chrominance component at the output of the bridged-T network to provide a separated luminance component at the output of the bridged-T network. The bridged-T filter and the bandpass filter cooperate to produce a double-tuned chrominance passband response for selectively passing signal frequencies of the chrominance component to yield a separated chrominance component at the output of the bandpass filter.

摘要翻译： 彩色电视接收机中的复合滤波器包括桥接T网络和色度带通滤波器，用于相互分离彩色电视信号的亮度和色度分量。 在桥接T网络中，第一和第二信号路径耦合在电视信号的输入源和输出之间，第二路径包括第一电抗。 包括第二电抗的第三信号路径被耦合在第二路径中的中间点和带通滤波器的输入端之间。 第一和第二电抗被调谐到色度分量的彩色副载波信号的频率。 第四个电阻信号路径耦合在带通滤波器的输入端和参考电位之间。 四个信号路径形成第一滤波器，用于衰减桥接T网络的输出处的色度分量，以在桥接T网络的输出处提供分离的亮度分量。 桥接T滤波器和带通滤波器协调产生双调谐色度通带响应，用于选择性地通过色度分量的信号频率，以在带通滤波器的输出处产生分离的色度分量。