Abstract: An improved automatic scan tracking servo for use in a magnetic recording and reproducing apparatus is disclosed. The automatic scan tracking servo operates generally in the digital domain. The apparatus has a movable element which is transversely moved relative to the longitudinal direction of a recorded track so that the transducing head can be made to accurately follow the track during special motion reproducing modes. The RF video signal is sampled a predetermined number of times during each rotation of the scanning drum carrying the transducing head. The phase of the oscillatory motion or dither that is applied to the movable element carrying the head, the operation of a synchronous detector and the sampling are all totally synchronized to obtain an accurate error signal so that an accurate error correcting signal can be generated to have the transducing head accurately follow a track during such reproducing.

Abstract: A small, very low cost, wide margin core memory couples a return current drive scheme with a crossover-free sense winding extending parallel to the Y drive conductors to eliminate the assembly time and wasted substrate space associated with sense winding crossovers. The return currents generate small noise signals which cancel with partial select noise signals to provide noise signals comparable to a 3 wire, 3D bow tie sense winding.

Abstract: An encoder verifier checks the functioning of a Reed-Solomon encoder in which data and parity bytes are intended to be digitally encoded in data blocks to form for each data block a respective codeword in multi-bit bytes in the form of a Galois field polynomial that is divisible in the Galois field by a generator polynomial, such generator polynomial being the Galois field product of a plurality of factors. A Galois field polynomial divider divides respective codewords by one of the factors to produce a remainder signal systematically related to the remainder from such division. An indicator responsive to the remainder signal produces an indication of encoder malfunction when the remainder signal corresponds to a remainder other than zero.

Abstract: A highly efficient core memory drive system passes currents down a selected X and Y conductor and divides the currents for return through the unselected drive wires in the same X or Y dimension. The drive conductors are coupled to drive and sink switches at a drive end and the X conductors are connected together at an opposite common end and the Y conductors are connected together at an opposite common end. Resistors provide a current path between the drive end of each X conductor and an X resistor bus and between the drive end of each Y conductor and a Y resistor bus. A pair of switching transistors including a sink transistor and a drive transistor is connected to a drive end of each conductor to generate a drive current therein. The drive current divides equally among the unselected conductors at the common end to return through the unselected conductors and through the resistors to the resistor bus.

Abstract: A device in which at least two separate electrical connections are made between a first member and a second member. The first member has at least two surfaces with at least one conductive element on each surface. These conductive elements are insulated from one another. The second member is mounted in an aperture of the first member. Electrically conductive regions of the second member, insulated from one another, are connected to the conductive elements of the first member.