公开(公告)号：US3927255A

公开(公告)日：1975-12-16

申请号：US46589174

申请日：1974-05-01

Applicant: RCA CORP

Inventor： YORKANIS BERNARD JOSEPH

IPC: H04N5/18 ,  H04N5/44

CPC classification number: H04N5/185

Abstract: A clamping circuit is included in the video processing section of a television signal processor and is arranged to clamp the pedestal or black level of the video signal to a reference voltage manifesting the black tone output of the receiver. The clamping circuit includes capacitive means responsive to the video signal, a reference voltage source for generating the reference voltage, a current source for generating current for charging the capacitive means, and a unidirectional conducting device for coupling the reference voltage source and the current source to the capacitive means and poled to clamp the signal excursions of one relative polarity developed at the output of the capacitive means to the reference voltage. The reference voltage source is arranged to maintain the reference voltage substantially invariant in response to video signal variation. The current source is peak current limited to prevent the capacitive means from being charged in response to the peaks of noise pulses occurring in the video signal. In a preferred arrangement, means are also provided to prevent the capacitive means from being charged in response to the sync pulse superimposed on the pedestal level.

Abstract translation: 钳位电路包括在电视信号处理器的视频处理部分中，并且被配置为将视频信号的基座或黑色电平钳位到表示接收器的黑音输出的参考电压。 钳位电路包括响应于视频信号的电容装置，用于产生参考电压的参考电压源，用于产生用于对电容装置充电的电流的电流源，以及用于将参考电压源和电流源耦合到的单向导通装置 电容装置，并被极化以将在电容性装置的输出处产生的一个相对极性的信号偏移钳位到参考电压。 参考电压源被布置为响应于视频信号变化而保持参考电压基本上不变。 电流源是限制的峰值电流，以防止电容性装置响应于视频信号中出现的噪声脉冲的峰值而被充电。 在优选的布置中，还提供了用于防止电容装置响应叠加在基座电平上的同步脉冲而被充电的装置。

公开(公告)号：US3925790A

公开(公告)日：1975-12-09

申请号：US46399674

申请日：1974-04-25

Applicant: RCA CORP

Inventor： FISHBECK KENNETH HENRY

IPC: B41J2/145 ,  H04N1/032 ,  G01D15/18

CPC classification number: H04N1/032 ,  B41J2/145 ,  Y10S101/37

Abstract: A non-impact printing apparatus including a disc having marker units located at the periphery of the disc. The marker units are operated in response to a control signal to mark picture elements of an output copy guided past an arcuate portion of the periphery of the disc. The printing apparatus includes a data demultiplexer to selectively couple the control signals to the marker units according to a predetermined sequence wherein adjacent picture elements of the output copy are not printed by the same marking unit to thereby prevent the formation of linear patterns readily perceptable to the human eye.

Abstract translation: 一种非冲击式打印设备，包括具有位于盘周边的标记单元的盘。 标记单元响应于控制信号而被操作，以标记经过盘周边的弧形部分的输出副本的图像元素。 打印设备包括数据解复用器，用于根据预定顺序选择性地将控制信号耦合到标记单元，其中输出副本的相邻图像元素不被同一标记单元打印，从而防止形成容易被感知的线性图案 人类的眼睛。

公开(公告)号：US3925688A

公开(公告)日：1975-12-09

申请号：US54515875

申请日：1975-01-29

Applicant: RCA CORP

Inventor： KALFUS MARTIN AARON

IPC: H03K17/13 ,  H03K17/72

CPC classification number: H03K17/136

Abstract: An input signal having a period T is applied to a series connected load and triggerable bidirectional switch. A zero crossing detector provides a trigger pulse at each axis crossing of either the input signal or the voltage across the switch. A circuit, including a monostable multivibrator triggered at alternate axis crossings of the input signal and having an ONperiod between T/2 and T, applies the detector trigger pulses to the switch during the ON-period. Triggering of the multivibrator is controlled by a further circuit so that switching at the zero crossings of the input signal or the potential across the switch for an integral number of cycles is thereby provided during the period that the multivibrator is triggered.

Abstract translation: 具有周期T的输入信号被施加到串联连接的负载和可触发的双向开关。 过零检测器在切换开关的输入信号或电压的每个轴交叉处提供触发脉冲。 包括在输入信号的交替轴交叉处触发并具有T / 2和T之间的导通周期的单稳态多谐振荡器的电路在接通时段期间将检测器触发脉冲施加到开关。 多谐振荡器的触发由另一个电路控制，从而在多谐振荡器被触发的时间段期间提供在输入信号的零交叉处或开关两端的电位之间进行整数倍的切换。

公开(公告)号：US3925657A

公开(公告)日：1975-12-09

申请号：US48174674

申请日：1974-06-21

Applicant: RCA CORP

Inventor： LEVINE PETER ALAN

IPC: H01L27/148 ,  H04N5/372 ,  H01J39/12

CPC classification number: H04N5/372 ,  H01L27/14806 ,  H01L27/14831 ,  H04N5/32 ,  H04N5/357

Abstract: Bias or background charge (sometimes known as ''''fat zero'''' charge) is introduced into a charge coupled device (CCD) image sensing array by applying radiation to the substrate through the surface opposite the one receiving the image. For example, in the case of a front surface illuminated array, bias light is projected through the rear surface of the substrate to introduce the background charge.

Abstract translation: 将偏置或背景电荷（有时称为“脂肪零”电荷）引入到电荷耦合器件（CCD）图像感测阵列中，通过与接收图像的面相反的表面向衬底施加辐射。 例如，在前表面照射阵列的情况下，偏置光通过衬底的后表面投射以引入背景电荷。

公开(公告)号：US3925237A

公开(公告)日：1975-12-09

申请号：US48408574

申请日：1974-06-28

Applicant: RCA CORP

Inventor： ROSS DANIEL LOUIS ,  GAVRILOVIC DRAGAN MILAN

IPC: C09K19/00 ,  C09K19/32 ,  C09K3/34 ,  C07C121/50 ,  C07C121/60 ,  C07C121/66 ,  C07C121/74 ,  C07C121/75 ,  C07C121/76 ,  G02B5/23

CPC classification number: C07C255/00 ,  C09K19/322

Abstract: Nematic liquid crystal compounds of the

WHEREIN X can be R-, RO-,

and wherein R is an alkyl group of 1-10 carbon atoms have positive dielectric anisotropy and are useful in field effect electrooptic cells which comprise a thin liquid crystal layer between two closely spaced parallel electrodes.

公开(公告)号：US3924974A

公开(公告)日：1975-12-09

申请号：US45616274

申请日：1974-03-29

Applicant: RCA CORP

Inventor： FISCHBECK KENNETH HENRY ,  LEYTON ERIC MCPHAIL

IPC: B41J2/175 ,  B41J2/045 ,  B41J2/055 ,  F04B43/09 ,  G01D15/16 ,  H04N1/034 ,  F04B17/00 ,  B05B1/08 ,  B05B17/04 ,  G01D15/18

CPC classification number: B41J2/04 ,  F04B43/09

Abstract: A tube-like chamber for ejection of fluid is formed of magnetostrictive material. In a preferred form, the chamber contains a nozzle through which fluid contained in the chamber may be ejected as the volume of the chamber is decreased through magnetostrictive action. In cross-section, the chamber is preferably formed of two arcs of respective circles. The chamber is formed of a first type of magnetostrictive material such that the arcs contract circumferentially in response to a circumferential magnetic field induced in tube in the direction of the length of the arcs. A flat member is disposed along the axis of the chamber and spans between opposite portions of the wall of the chamber. In cross-section, the flat member forms a chord of the two arcs. The flat member is formed of a second magnetostrictive material such that the chord expands in the direction of span in response to a lateral magnetic field induced in the flat member in the direction of span of the flat member. The flat member is in contact with the arcs, and thereby, an efficient closed loop magnetic field path comprising the two arcs and the chord is formed. When a circumferential magnetic field is induced in the chamber and a lateral magnetic field is induced in the flat member, the arcs contract circumferentially and the chord expands in the direction of span thereby causing the shape of the cross-section of the tube to distort. As a result of this distortion, the volume of the chamber is substantially decreased and fluid is ejected from the nozzle.

公开(公告)号：US3924266A

公开(公告)日：1975-12-02

申请号：US50196374

申请日：1974-08-30

Applicant: RCA CORP

Inventor： HARWOOD LEOPOLD ALBERT

IPC: H04N9/77 ,  H04N9/02

CPC classification number: H04N9/77

Abstract: In a television signal processing system, including separate channels for processing luminance and chrominance signal portions of a composite video signal, apparatus is provided for automatically varying the bandwidth of the luminance channel in accordance with the amplitude of color information signals. In an illustrated arrangement, apparatus for controlling the bandwidth of the luminance channel is coupled to a color demodulator circuit which is included in the chrominance channel for generating, for example R-Y, G-Y and B-Y color difference signals. The bandwidth of the luminance channel is controlled to vary in inverse relationship to the amplitude of the demodulated color difference signal having the largest amplitude.

Abstract translation: 在包括用于处理复合视频信号的亮度和色度信号部分的单独信道的电视信号处理系统中，提供了根据彩色信息信号的幅度来自动改变亮度信道带宽的装置。

公开(公告)号：US3924192A

公开(公告)日：1975-12-02

申请号：US47608174

申请日：1974-06-03

Applicant: RCA CORP

Inventor： GEORGE JOHN BARRETT

IPC: H03J5/02 ,  H03J7/28 ,  H04B1/32

CPC classification number: H03J5/0245 ,  H03J7/28

Abstract: A television tuning system wherein voltage tunable tuners are supplied with a tuning voltage suitable for receiving a particular selected channel. The tuning voltage is produced by a sweep generator. A harmonic generator produces harmonically related reference signals at frequencies corresponding to television channel oscillator frequencies. A frequency discriminator produces an output representative of frequency differences between the oscillator signal and each of the harmonically related signals as said tuning is varied. A counter coupled to the discriminator produces an output count representative of the oscillator signal passing through a predetermined frequency relationship with respect to each of the harmonically related signals. A channel selector produces a stored count representative of a selected television channel. A comparator provides a hold signal to the sweep generator in response to a match between the output count and the stored count. A decoder identifies the presence of a first and a second particular output count. A band switch produces a signal to condition the voltage tunable tuners for reception of a first band of radio frequencies when the output count is less than or equal to a first particular count and to condition the voltage tunable tuners for reception of a second band of radio frequencies when the output count is greater than the first particular count. The band switch also conditions the voltage tunable tuners for reception of a third band of radio frequencies when the output count is greater than the second particular count. The sweep generator is reset, in response to a match between the output count and the first or second particular count, to a condition suitable for initiating variation of the tuning of the local oscillators through a fifth or sixth band of frequencies, respectively.

Abstract translation: 一种电视调谐系统，其中电压可调谐调谐器被提供有适于接收特定选定通道的调谐电压。 调谐电压由扫描发生器产生。 谐波发生器在对应于电视频道振荡器频率的频率处产生与谐波相关的参考信号。 当所述调谐变化时，鉴频器产生表示振荡器信号和每个谐波相关信号之间的频率差的输出。 耦合到鉴频器的计数器产生表示相对于每个谐波相关信号经过预定频率关系的振荡器信号的输出计数。 信道选择器产生代表所选电视频道的存储计数。 响应于输出计数和存储的计数之间的匹配，比较器向扫描发生器提供保持信号。 解码器识别第一和第二特定输出计数的存在。 当输出计数小于或等于第一特定计数时，频带开关产生信号以调节电压可调谐调谐器以接收第一波段频率，并且调节电压可调谐调谐器以接收第二频带无线电 当输出计数大于第一个特定计数时的频率。 当输出计数大于第二特定计数时，频带开关还调节用于接收第三频带频带的电压可调谐调谐器。 响应于输出计数和第一或第二特定计数之间的匹配，扫描发生器被复位到适于分别通过第五或第六频带启动本地振荡器的调谐变化的条件。

公开(公告)号：US3924159A

公开(公告)日：1975-12-02

申请号：US51222574

申请日：1974-10-04

Applicant: RCA CORP

Inventor： HOOVER MERLE VINCENT

IPC: H02H3/36 ,  H03F1/52 ,  H02H3/08 ,  H02H7/20

CPC classification number: H02H3/36 ,  H03F1/52

Abstract: An emulating amplifier stage, that can be lower in power capability but otherwise has the same electrical operating parameters as the amplifier output stage being protected, forms a bridge network with this output stage. A resistor is connected between two nodes of the bridge (between the output terminals of these stages). When a fault occurs, such as a short circuit across the load being driven by the amplifier, the bridge network becomes unbalanced and current flows through the resistor. In response thereto, the drive signal and bias voltage are removed from the input circuit of the output stage.

Abstract translation: 仿真放大器级可以在功率能力较低的情况下具有与放大器输出级保护相同的电气工作参数，与此输出级形成桥接网络。 电阻器连接在桥的两个节点之间（在这些级的输出端子之间）。 当故障发生时，例如负载由放大器驱动的短路，桥接网络变得不均衡，电流流过电阻器。 响应于此，从输出级的输入电路去除驱动信号和偏置电压。

公开(公告)号：US3923685A

公开(公告)日：1975-12-02

申请号：US40754673

申请日：1973-10-18

Applicant: RCA CORP

Inventor： OH CHAN SOO ,  PASIERB EDWARD F

IPC: C07C45/71 ,  C09K19/58 ,  C09K3/34

CPC classification number: C09K19/586 ,  C07C45/71 ,  C09K19/582 ,  C07C47/575

Abstract: Liquid crystal cells containing mixtures of cholesteric optically active p-alkoxybenzylidene-p''-aminobenzonitrile compounds with nematic liquid crystal compounds form cholesteric liquid crystals which change to the nematic state upon application of an electric field. Electro-optic devices including such liquid crystals have low voltage requirements and rapid response times.

Abstract translation: 含有胆固醇光学活性对 - 烷氧基亚苄基 - 对氨基苯甲腈化合物与向列型液晶化合物的混合物的液晶单元形成胆甾型液晶，其在施加电场时变为向列状态。 包括这种液晶的电光器件具有低电压要求和快速响应时间。