Abstract: An improved magnetic head structure which places a laminate at the gaps of the head, said laminate deposited on each substrate facing the gap, and comprising alternating layers of first and second magnetic materials, said first material having a higher coercivity than said second material.

Abstract: Velocity errors in a video signal are sampled at scan line rate and are averaged over a selected plurality of frames to enhance the repetitive velocity errors while cancelling the random velocity errors. The resulting separated repetitive velocity errors then are subtracted from the initial combined velocity errors to provide separated random velocity errors. A repetitive error interlace technique is used to generate an improved repetitive error frequency control signal, while a second order correction technique provides a corresponding random error frequency control signal. The two frequency control signals are combined and the combined signal is used to provide compensation for the initial velocity errors.

Abstract: A deskew processor includes first and second memory units each having independent data write control circuits and data read control circuits. The write control loads successive data into respective memory units as it is received, and the read control reads the data out of the memory units into a data selector circuit as determined by a data selector control circuit. The latter determines the presence of any data overlap and delays read out of data via the data selector circuit until the previous data is completely read, thereby deskewing the successive data.

Abstract: A method and apparatus for producing a video composite blanking signal which provides for selectively unblanking lines of video information which would normally be blanked according to a predetermined television standard. Each line in a frame of video data is assigned a line type based on its location in the sequence of lines of video information. Those lines that are in the vertical blanking period are assigned a different line type than those which are not. In response to unblanking selection data, line types of lines which are normally blanked are selectively modified to the line types of those lines which are not normally modified. The vertical interval blanking signal is produced only for those line types for line in the vertical blanking period.

Abstract: A VTR controller provides an internal counter which counts a frame reference to provide a number representing the position of the reference in the video color sequence. This numbr must be synchronized to the color sequence of the station reference in order to be useful. To synchronize the internal counter in an automated system, the controller places the VTR into color framed playback mode and, after a sufficient period of time, the position of the current time code value in the color sequence is computed. The position is the value that the internal counter should have at that instant in time. The value is loaded into the counter and its output is the color frame sequence number. In a manual embodiment, an operator makes a test edit with the VTR color framer off, to determine if the value in the internal counter is correct and, if not, corrects the value. Prior to the actual edit process, another computation is performed to determine the start of the time lines which control the edit process.

Abstract: In a tape drive system, a dynamic brake control circuit provides dynamic braking for slowing and stopping an associated tape reel and motor system in the event of a power failure. Upon sensing a power failure, the electrical energy stored in a capacitor supplies electrical energy to enable the control circuit, which in turn supplies a controlled conductive path for the flow of a dynamic braking current due to the back electromotive force signal generated by the motor, to effect the controlled dynamic braking of the drive motor to a stop.

Abstract: An apparatus and method for generating waveform signals for the production of a variety of borders for video wipes by varied processing of the output of a ramp generator.

Abstract: A digital time base corrector for correcting time base errors of the digital samples of a video signal for all the various speed modes of a reproducing apparatus. The time base corrector is configured having a small capacity memory and a large capacity memory wherein the small capacity memory is divided into a first section and a second section. The first section of the small capacity memory retimes data samples for subcarrier phase errors without losing or repeating data, while the second section of the small capacity memory retimes data for horizontal frequency error without losing or repeating data in all reproducing modes except shuttle. Further, the second section of the small capacity memory in reverse and forward shuttle retimes the data for horizontal frequency and phase errors while equalizing the data rate through the time base corrector by selectively discarding or repeating horizontal lines based on line type.

Abstract: A video recording system employs an editing device to communicate schedules of instructions to a videotape recorder control system which, in turn, communicates selected ones of the instructions from the schedules to a time-base corrector so that the time-base corrector automatically controls and adjusts video signal parameters at the output of the videotape recorder in accordance with an appropriate one of the schedules. Operation of the system includes the steps of storing schedules of instructions in the editing device, communicating the schedules of instructions to a videotape recorder control system connected to a time-base corrector, storing time lines of the instructions in the videotape recorder control system, and operating the time-base corrector to manipulate video signal information at the output of a recorder mechanism according to the time line schedules.

Abstract: A system and method are described for aligning a set of tracks which have been recorded simultaneously on a magnetic medium by a multichannel transducer mounted in a rotating scanner, with transducing channels of a corresponding multichannel transducer for reproduction. A scan identifier signal is recorded simultaneously by a rotating multichannel transducer at a predetermined location along each track. Means are provided for reproducing and summing simultaneously accessed scan identifier signals during consecutive scans of the multichannel transducer over the medium. The relative position of the recorded medium to the rotating multichannel transducer is changed in a direction across the length of the tracks. That relative position in which the largest amplitude of the summed scan identifier signals is obtained corresponds to the desired alignment with the set of tracks.

Abstract: A system to improve image quality during shuttling of a video tape in a record and playback machine of the type in which each image field is recorded on one or more tracks on video tape. The system includes an offset signal source coupled to a displaceable mechanism during shuttling to provide relative displacement between a reproduce transducer and a video tape to cause the transducer to cross tracks of recorded information irregularly, thereby providing frequent updating of substantially all regions of an image field by information stored on the tape.

Abstract: An adaptive dropout compensator is fully digital and employs an adaptive logic circuit to detect dropout characteristics such as the extent thereof and the best available replacement data, and generates an adaptive logic decision for supplying the optimum replacement data. The circuit configuration lends itself to a switchable implementation for accommodating the various color television standards.

Abstract: A magnetic shield is provided for stray flux reduction from a transducer into a laterally disposed adjacent transducer. The shield substantially covers the transducing winding and extends in close proximity over a rear portion of the magnetic core. The shield does not extend over the transducing gap, to prevent magnetic coupling therewith. In the preferred embodiment a staggered two channel video type transducer has shields on opposite sides thereof in direct contact with the cores. The shields have recesses to accommodate the windings.

Abstract: Video channel combines are produced by digitally processing binary numbers representing values of video image information in multiple channels, for corresponding points in a display of the resulting composite video image. The binary numbers are combined in the course of processing in response to processed key signals which determine a preselected percentage of each binary number's value, to produce new binary numbers. After summation, the latter represent composite video image values to be displayed at the same temporal and spatial locations of the display of the composite video image. Total percentages resulting from the summation of all numbers for each composite video image value, including numbers corresponding to percentage of background video, is equal to 100%.

Abstract: Digital data is received on a plurality of input channels at unrelated, asynchronous input clock rates. The data is multiplexed and transmitted via one or more synchronous parallel channels, together with encoded information related to the original asynchronous input clock rate on each channel. The data received from the synchronous channels is demultiplexed and redistributed to proper output channels and clocked out therefrom at rates derived from the encoded and reconstituted asynchronous clock rate information from each channel.

Abstract: A method and apparatus for controlling the capstan servo of a magnetic video tape recording and reproducing machine is disclosed. The invention provides almost instantaneous color framing and synchronous control track lock when accelerating from a very slow tape velocity up to normal velocity. An embodiment of the apparatus also stops the tape at a predetermined position relative to control track transitions when stopping the machine from a noncontrol track lock operating mode, such as shuttle, variable velocity reproducing and jog.

Abstract: A bar code reader system includes a stream of pulses whose period is a function of the scan speed of the reader as it scans the bars and spaces of a bar code symbol. Transition pulses are supplied which identify the boundaries of the bars and spaces. The tach pulses which occur between transition pulses are counted, loaded into memory, and are read from memory via microprocessor means, whereby the widths of the bars and spaces are determined. The sequence of the bar and space data is decoded to yield the bar code encoded numbers.

Abstract: Apparatus for tensioning tape extending between two reels in a tape transport system having servos for controlling the velocity and position of the reels, includes position servo loop for maintaining the first reel in a fixed position. A velocity servo loop controls the other reel for taking up slack in the tape between the reels and applying a relative force on the tape once the slack has been taken up. The velocity servo is limited in the amount of current applied to the motor driving the take up reel by a signal provided by a tension servo connected to the position servo associated with the other reel. In particular, the tension servo responds to the amount of current applied by the position servo for applying a motor-current-limiting signal to the velocity servo system. When the position servo is applying minimal current to the fixed-position reel (when the tape is slack), a relatively large amount of current is allowed to go to the take up reel.

Abstract: A digitally controlled motor drive system using a pulse width modulated motor drive receives a desired motor velocity signal and an actual motor velocity signal and it provides a corresponding velocity error signal. The velocity error signal is adjusted in response to a change in the value of a power voltage supplied to the motor. The velocity error signal may be compensated for back electromotive force and/or for static friction in the motor, if desired. The system is simple, reliable and cost effective.