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Patent Agency Ranking1.发明授权Television automatic gain control circuitry providing for compatible control of vhf tuner and uhf tuner 失效电视自动增益控制电路提供兼容甚高频调谐器和UHF调谐器的控制
公开(公告)号：US3823379A
公开(公告)日：1974-07-09
申请号：US36264473
申请日：1973-05-21
Applicant: RCA CORP
Inventor： GEORGE J
CPC classification number: H03G3/3068
Abstract: A television automatic gain control circuit which transforms the low input impedance of the gain control terminal of a stage such as a grounded base bipolar transistor RF amplifier of a UHF tuner or a PIN diode attenuator utilized for tuner gain reduction to an impedance comparable to that of the impedance of the gain control terminal of an MOS/FET transistor used as an RF amplifier of a VHF tuner. Additionally, the control circuit provides for clamping of the AGC voltage at a selected level to provide AGC delay different from VHF AGC delay. Also, a predetermined voltage offset is provided to translate the AGC voltage applied to the RF amplifier of the VHF tuner before being applied to the gain controlled stage of the UHF tuner.
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2.发明授权
公开(公告)号：US3766313A
公开(公告)日：1973-10-16
申请号：US3766313D
申请日：1972-08-07
Applicant: RCA CORP
CPC classification number: G06F15/02
Abstract: A desk top calculator or other generator of digitized video signals is coupled to the antenna terminals of a conventional television receiver. A circuit within the generator translates the digitized video signals into a modulated TV R-F picture carrier. The circuit includes a radio-frequency source, and a network of diode switchable attenuators. The latter are operated in response to control signals for switching the radio-frequency signal between three discrete levels. Two of the levels are for the display of black and white, respectively, and the third level is a ''''blacker than black'''' synchronization level.
Abstract translation: 数字化视频信号的桌面计算器或其它发生器耦合到常规电视接收机的天线端子。 发生器内的电路将数字化的视频信号转换成调制的TV R-F图像载体。 该电路包括射频源和二极管可切换衰减器的网络。 后者响应用于在三个离散电平之间切换射频信号的控制信号来操作。 其中两个级别分别用于显示黑白，第三级是“黑色比黑色”同步级别。
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公开(公告)号：BR7410731D0
公开(公告)日：1975-09-02
申请号：BR1073174
申请日：1974-12-23
Applicant: RCA CORP
Inventor： GEORGE J
Abstract: Synchronous video detection in a television receiver provides increased detection linearity and better signal-to-noise ratio for weak signals than does envelope video detection. Impulse noise, which produces generally unobtrusive black-going noise components in a picture reproduced in response to a video signal recovered by envelope detection from a negatively modulated carrier also produces obtrusive white-going noise components in a picture reproduced in a response to a video signal recovered by synchronous detection. Common signal processing means, responsive to the envelope of the video signal modulated intermediate frequency carrier, inverts the white-going noise impulses to produce black-going components so that substantially all noise impulses appear black-going in the recovered signal.
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公开(公告)号：SE366440B
公开(公告)日：1974-04-22
申请号：SE358071
申请日：1971-03-19
Applicant: RCA CORP
Inventor： GEORGE J , HILLIKER S
Abstract: An ultra high frequency (UHF) tuner includes a plurality of tunable transmission lines formed on a dielectric plate. At least two of the transmission lines are tunable over different bands of frequencies and each includes first and second conductive sections, coupled by voltage responsive capacitance devices, disposed on one surface of the dielectric plate, and a conductive ground plane disposed on the other surface overlying the first and second sections. One end of the first section of each of the transmission lines is connected to the ground plane and is shaped to provide tracking as the transmission lines are tuned across their respective frequency bands. An adjustable inductor serially connected with the variable capacitance devices also provides a tracking adjustment between the circuits.
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公开(公告)号：CA932821A
公开(公告)日：1973-08-28
申请号：CA106570
申请日：1971-03-01
Applicant: RCA CORP
Inventor： GEORGE J , HILLIKER S
IPC: H03B5/18
Abstract: An ultra high frequency (UHF) tuner includes a plurality of tunable transmission lines formed on a dielectric plate. At least two of the transmission lines are tunable over different bands of frequencies and each includes first and second conductive sections, coupled by voltage responsive capacitance devices, disposed on one surface of the dielectric plate, and a conductive ground plane disposed on the other surface overlying the first and second sections. One end of the first section of each of the transmission lines is connected to the ground plane and is shaped to provide tracking as the transmission lines are tuned across their respective frequency bands. An adjustable inductor serially connected with the variable capacitance devices also provides a tracking adjustment between the circuits.
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