Abstract: A digital storage system of the Winchester or hard disk drive type has the annular, hard aluminum disks mounted coaxially around the drive motor. A central fixed aluminum shaft has the motor stator coils centrally mounted on it, and an aluminum disk mounting sleeve is mounted to the shaft by bearings located above and below the motor stator. To accommodate the difference in thermal coefficients of expansion between the steel cylinder forming the outer periphery of the motor's rotor and the aluminum disk assembly, the outer steel cylinder of the motor rotor is bonded to the aluminum disk sleeve by means of an elastic adhesive, which permits relative expansion between the steel and aluminum parts occasioned by changes in temperature of the drive. The rotor, including its permanent magnets and outer steel cylinder, is mounted from the inner surface of the aluminum disk mounting sleeve, with the rotor in operating proximity to the stator.

Abstract: A digital storage system of the Winchester or hard disk drive type has the hard aluminum disks mounted around the drive motor. To accommodate the difference in thermal coefficients of expansion of the steel cylinder forming the outer periphery of the motor, and the aluminum disk assembly, an aluminum disk mounting sleeve is provided which extends for the full height of the disk assembly, and makes a thermal shrink fit around the steel motor cylinder, with the engagement between the two parts being limited to a section toward the center of the overlapping surfaces of the two parts. The aluminum storage disks and spacers between them have a slight clearance from, and are clamped between the top and bottom of the aluminum mounting sleeve.

Abstract: A phase locked loop having a second controllable oscillator connected to mix with the input signal to alter the frequency thereof toward phase lock and a pair of comparators with predetermined upper and lower limits therein connected to the control signal of the phase locked loop and controlling the controllable oscillator whenever the control signal is outside of the predetermined limits.

Abstract: An improved method of preparing hydrolyzed alkyl silicate binders useful in manufacturing protective coatings, i.e., zinc-rich coatings, is described wherein the hydrolysis is catalyzed in the presence of a strong acid form ion exchange resin instead of a conventional acid catalyst.

Abstract: The acquisition means includes a voltage controlled oscillator, comparison means for comparing an input signal to a signal from the voltage controlled oscillator, filtering means and a summing network connected in a phase-locked loop and providing an output signal at an output thereof at the input of said summing network, a signal multiplying network connected to receive the input signal and a signal from the VCO of the phase-locked loop and providing an output signal approximately 90 degrees out of phase with the output signal of the phase locked loop and two all pass networks connecting the output signals from the multiplying network and the phase locked loop to two inputs of a multiplier which has an output connected to the summing network, the all pass networks being designed to shift the phases of the signals so that they are in phase when applied to the multiplier.

Abstract: The disclosed signal generating apparatus and method is suitable for use in combination with a PM receiver to provide a standby signal for a signal processor. The standby signal system includes a clipper connected to the receiver IF; a coherent amplitude detector coupled between the clipper and a gain controlled amplifier; and a trigger circuit coupled between the coherent amplitude detector and the signal processor. The trigger circuit provides a standby signal in response to the level of the output signal of the coherent amplitude detector passing through a predetermined threshold level in response to the clipper limiting on a selected signal-to-noise ratio which occurs before the information signal becomes undesirably weak.

Abstract: A switching circuit of the type including a plurality of differential amplifiers on an IC chip and having a linear operating range about a bias point, having an operational amplifier connected as a comparator and coupled to an input thereof to receive a modulating signal, one input of the comparator being connected to the bias point so that the output thereof applied to the switching circuit varies about the bias point within the linear range of the switching circuit, and means coupling the signal to be modulated to a second input of the switching circuit so that the signal is bi-phase modulated by the modulating signal with substantial carrier suppression and significantly reduced harmonics.

Abstract: A demodulator for demodulating a phase modulated (PM) or frequency modulated (FM) signal into a baseband signal includes detector arrangement for converting said PM or FM signal into two outputs, means for summing the two outputs and means for modifying the summed outputs to generate the baseband signal of substantially the same amplitude across its frequency spectrum.