Abstract: A recorded medium moving at some operational velocity is rapidly stepped to advance or retard the position thereof by a preselected time segment relative to a reference clock and the stepping cycle is completed simultaneously with the recorded medium being returned to its operational velocity.
Abstract: A sync generator system for PAL-B television features an offset subcarrier generator that provides an offset subcarrier signal that has phase steps of ninety degree magnitude and occur twice per field. This makes smoothing of a PLL error voltage relatively easy.
Abstract: In a VTR of the type having information recorded in adjacent tracks disposed angularly across the direction of tape travel, a search mode playback arrangement is incorporated having a pair of transducer gaps which are alternately enabled to continuously pickup coherent information while the playback arrangement scans across adjacent tracks during a search mode.
Type:
Grant
Filed:
November 25, 1980
Date of Patent:
June 14, 1983
Assignee:
RCA Corporation
Inventors:
Lee V. Hedlund, Donald G. Herzog, Franz L. Putzrath
Abstract: A color encoding filter for use with a discrete photosensor pickup device has vertical stripes. The stripes occur in repeating cycles of color order, with the ratio of the width of a cycle to the width of a photosensor being a non-integer. This results in wider bandwidth in a luminance signal.The resulting pickup device output signal comprises a double sideband suppressed carrier signal having subcarriers conveying the chroma information. Both subcarriers can be demodulated, however demodulating only the upper sideband reduces biasing.
Abstract: A television synchronization generator has a clock generator driving a ROM. The ROM has stored in it the required sync signals. In order to conserve the ROM size, the ROM is addressed by a counter except during portions of the sync signals when the amplitude remains a constant. During these portions the counter continues to count.
Abstract: Under certain conditions a video disc player can be responsive to externally applied interference signals to provide a defect in the display of the information recovered from the disc. Apparatus is provided to reduce the influence of the extraneous signal to the playback display. The apparatus includes an automatic gain controlled amplifier and a level detector which provides two output signals. One of the output signals is used to control the amplifier gain. When the other output signal reaches a certain level it is used to develop a signal which initiates corrective action in the player.
Abstract: Electrical contact with the target electrode of the tube in a tube/coil assembly is made by disposing a wire tangentially to a radial periphery about the longitudinal axis of the tube to create an interference fit between the wire and the electrode.
Abstract: A suppression circuit processes the video signal from an anti-comet tail (ACT) image pickup tube and develops a control signal indicative of illumination highlights exceeding a predetermined level. The control signal is coupled through ACT pulsing circuits to the control elements of the ACT image pickup tube to automatically enable the beam control element pulsing so as to increase the beam current only in the presence of an illumination highlight to force the recharging of the target to cathode potential in the area of the highlight.
Abstract: Method and apparatus for replacing defective video information in a video signal line comprises sampling the video signal. Video information from the preceding in-phase pixel and the subsequent in-phase pixel are averaged to form a replacement pixel. Weighting coefficients are generated based upon the amplitude difference between the next adjacent and semi-adjacent pixels having the same subcarrier phase. These weighting coefficients are used to determine the amount of information contribution of the previous and subsequent pixels to arrive at the closest video approximation of the defective pixel. Three times color subcarrier frequency sampling is preferred.
Abstract: A TDM scheme has a Y signal that is sampled at 14.32 MHz and every other sample is discarded. The discarded samples are 180.degree. out-of-phase from line-to-line. I and Q signals are sampled at one half this frequency and every other sample is discarded also 180.degree. out-of-phase from line-to-line on a given line. The discarded samples of Q and I are 180.degree. out-of-phase with respect to each other. This allows insertion of the retained I and Q samples into the retained Y samples to allow multiplexing.
Type:
Grant
Filed:
January 26, 1981
Date of Patent:
March 15, 1983
Assignee:
RCA Corporation
Inventors:
Robert A. Dischert, James J. Williams, Jr., Glenn A. Reitmeier
Abstract: An improved transmission arrangement for a color television signal includes a time-division multiplexing apparatus for alternately presenting for transmission through a single channel baseband signals defining the chrominance information of the television signal. In order to provide improved resolution, a store is coupled to the signal source for storing at a writing rate a first of the baseband components during the time at which it is generated. A read generator is coupled to the store for reading the stored baseband component at a higher data rate than that at which it was generated. The baseband component is transmitted through the single channel at the higher data rate.
Abstract: A dropout compensator for time spread digital television signals uses either horizontal or vertical averaging to replace a dropped out sample. The choice of direction is made in accordance with whichever direction has the least amount of change around the missing sample or pixel. The circuitry can also be used for chroma invertion when stop or slow motion is to be transmitted or recorded.
Abstract: A dropout compensator includes an estimator for forming continuous estimates of the value of a video signal subject to dropouts. In order to determine the presence of a dropout, the estimated signal is compared with the actual signal to form a difference. When the difference exceeds a predetermined amount, the estimated value is substituted for the actual value.
Abstract: To continuously correct for tape stretching ("skew"), the phase of timed video information on the tape is compared with a reference at two different times, thereby forming two comparison signals. The two comparison signals are subtracted from each other to form an error signal, which is used to continuously correct the tape length variations.
Type:
Grant
Filed:
June 20, 1980
Date of Patent:
January 11, 1983
Assignee:
RCA Corporation
Inventors:
James W. Chamberlain, Arthur M. Goldschmidt
Abstract: A VCO control circuit features a first exclusive-OR gate to the inputs of which are applied signals derived from the VCO to provide an output signal that has a 90.degree. phase shift with respect to a reference signal. A second exclusive-OR gate serves as a phase detector for the output and reference signals and provides, after filtering, a frequency control voltage for the VCO. The control voltage has about the same amplitude regardless of the presence or absence of the reference signal.
Abstract: A speed control signal for a record segment is generated from starting speed and starting time information signals, an ending speed information signal, and a signal indicative of the duration of the segment. Provision is made for "pre-roll" (stopping the tape ahead of the exact cue point). Duration can be entered directly or computed from start and end times. The speed control signal is applied to a capstan servo, while a cue logic servo controls a reel servo.
Abstract: Apparatus for sharpening a diamond cutting stylus for use in recording video signal information in a metal master includes a source of high energy particles such as an ion milling machine. The high energy source provides a beam of high energy particles having a cross-sectional area perpendicular to the longitudinal axis of the beam that is large compared to a given area on a mounting face of the stylus which is to be bombarded by the beam during the sharpening operation. Further, the apparatus includes a masking block for masking a first portion of the cutting stylus. The masking block is positioned with respect to the high energy source to intercept the particles in the beam directed at the first portion of the cutting stylus. A second portion of the cutting stylus which includes the given area is exposed to the high energy particles such that the second portion of the cutting stylus is removed.
Abstract: An apparatus for providing component-to-composite and vice versa transcodings of a sampled video signal features generating steering bits that indicate which of combinations of surrounding samples of a composite signal has a component that provides the closest match to the corresponding component of an original component video signal. This allows successive transcodings with a minimum of crosstalk between components, e.g., luminance and chrominance.
Abstract: A high voltage generator of a television display is responsive to an alternating voltage, such as a retrace pulse voltage, for developing an ultor voltage at an ultor terminal. A protection circuit for the high voltage generator includes a comparator that develops a television display disabling signal when activated. A circuit that develops a sense voltage representative of the ultor voltage is coupled to an input terminal of the comparator so as to develop the disabling signal when the ultor voltage exceeds a predetermined level. To provide an overload disabling capability, an ultor beam current sensing circuit is coupled to the input terminal of an operational amplifier. The output terminal of the amplifier is coupled to a bias voltage source and to an input terminal of the comparator.
Abstract: In order to reduce the amount of hardware required in comparing 8-bit numbers representing digitized video signals, only the four LSB are compared, since if the numbers differ by more than the four LSB, no comparison is desired. This is done by detecting if any of the four MSB are logic "1", and if so, setting all of the four LSB to logic "1".
Type:
Grant
Filed:
August 26, 1980
Date of Patent:
July 20, 1982
Assignee:
RCA Corporation
Inventors:
James J. Williams, Jr., Robert A. Dischert