Abstract: A transistor amplifier in which collector to emitter voltages and currents are kept constant, particularly in the power output stages of the amplifying devices for minimizing distortion due to changes in the transistor beta, the essential form of distortion in amplifiers. High fidelity low power output current from a cascoded transistor amplifier is fed through a load to a second, high power, amplifier having constant current and less than unity gain, with an output summed with the output of the first amplifier such that the output of the first low power amplifier is the signal bearing portion and the output of the second amplifier serves as a current bootstrap, increasing the effective impedance of the load as seen by the first amplifier.

Abstract: A surface profile measuring instrument, which has a stylus supported on a counterbalanced scanner arm, in turn supported in a gimbal mounting having two axes, one of which is adjustable by a servo. A connected electronics package provides axis compensation for levelling through the servo, as well as zero adjustment of a display device and discrimination against small, unwanted slops. Stylus motion is translated into an analog signal by a linear position differential transformer. To achieve slope discrimination, the analog signal is differentiated and compared in a comparator to a reference for rejection of signals corresponding to small slopes. The signal is then integrated and displayed, with reference to a selected zero of a display device.

Abstract: An improved handle assembly for selectively carrying or releasing the contents of a disk cartridge or the like. The handle is a U-shaped member with a housing pivotally mounted between the open ends of the U-shaped member and which may rotate therebetween. The housing contains movable dogs for latching the housing to the arms of the U-shaped handle so that an assembly which is connected to the housing will move when the handle is released if the housing is latched to the arms by movement of the dogs.

Abstract: A ramp wherein a rigid framework supports a first pair of parallel ramp members of equal length to be mounted from the rear of a truck bed downwardly at an angle, clearing the ground. A second pair of ramp members is hinged to the first pair of ramp members and is folded over first pair when the ramp structure is not in use but is brought into substantially parallel alignment therewith when said ramp is used for loading purposes.

Abstract: A carrier bag for infants wherein a two-layer inner bag is provided with a lower support layer section and an upper pillow layer section. The inner bag is removably disposed within an outer bag having a quilt attached thereto so that an infant may be placed on top of the outer bag and covered with the quilt.

Abstract: A method and apparatus is disclosed whereby a solenoid coaxially surrounding an elongated electrically conducting material generates a radio frequency magnetic field of such a frequency that the material within excludes or displaces magnetic lines of force therefrom. One or more search coils are mounted coaxially within the solenoid, but outside of the material. By comparing the signal induced in the search coils when the material is present with the signal induced in the search coils when the material is absent, the outer cross sectional area of the material may be measured by measuring magnetic field exclusion or displacement, from the search coil andfrom this data, weight per unit length of solid material may be inferred. Furthermore, a pattern of deformations on the material may also be inferred, when the material is moving at known speed, from any high frequency modulation of the signal picked up by the search coil.

Abstract: A multi-element ophthalmic lens construction is disclosed wherein a plurality of two element lens pairs are bonded together to form an ophthalmic lens. Each pair forming a combination has internally mating, Fresnel reduced, corrector shapes. However, each element of the pair has a different index of refraction whereby each lens pair achieves a desired power.

Abstract: A method is disclosed whereby the molecules of a chemical substance to be measured, referred to as target molecules, are combined with fluorescent molecules having a relatively long fluorescent decay lifetime. These tagged target molecules are excited with an intense pulse of ultraviolet or visible radiation, and a detection system is gated on only after background fluorescence has substantially decayed, but while the fluorescent tag attached to the target molecules is still actively decaying. The amount of fluorescent tag emission which is measured is indicative of the target molecule content of the sample. An apparatus for improved fluorescent spectrofluorometry includes a pulsed excitation source and a gating means connected to a detection system for gating the detection system on after tagged target molecules have been excited and competing background fluorescence has substantially decayed, but before tagged target molecules have substantially decayed.

Abstract: A gauge for determining the mass per unit area, or alternatively the thickness of sheet material by measuring the attenuation, as well as backscatter, of an X-ray beam or the like, while continuously taking into account deviations and changes in localized material composition, insofar as these have an effect on the transmission coefficient of the beam. Electrical signals representing these deviations are combined with calibration data for given material nominal properties, i.e., nominal composition. The resultant and output signal represents the mass per unit area or thickness.

Abstract: A cable testing apparatus for multi-conductor cables including a test fixture for mechanically securing the cable to be tested. A plurality of tracks within the test fixture accommodates connectors of selected width. A control box which has a test lamp for each conductor energizes both the lamps and the conductors through a jumper cable for providing a continuity check through the tested conductors.

Abstract: A base plate mountable in a dental articulator, having a groove forming a closed curve therein. The groove defines a base plate of a smaller size, such that the larger base plate, containing the groove, may be fractured along the groove and a smaller base plate may be used in lieu of the larger one.

Abstract: A model for demonstrating a variety of crystal structures wherein vertical rods represent ionic or atomic coordinate axes and spheres movably mounted on the vertical rods represent ions or atoms is disclosed. A template covering some of the holes in a base defines a selected base hole pattern for establishing atomic coordinates. Spheres are of a selected size such that certain adjacent spheres are tangent to each other.

Abstract: A method of simultaneously preparing and plating two parts attached together in an assembly, which parts are of different materials, such as steel and aluminum, and are incompatible with one another in the plating preparation process. The method includes the steps, in the following order, of (a) degreasing such an assembly with trichloroethylene vapors for a period of 3 to 5 minutes, (b) clean with a heated alkaline cleaner for a period of 15 seconds, then rinse with water, (c) clean with muriatic acid for a period of 5 seconds, then rinse with water, (d) repeat steps (b) and (c) once again, (e) dip assembly in zincate solution for a period of 2 minutes, then rinse with water, and (f) plate the exposed surfaces of the assembly. The method also includes the steps of first cleaning the parts separately, attaching the parts together, and machining the assembly before initiating the above steps. An article constructed in accordance with the above is also disclosed.

Abstract: A plurality of Schmidt optical systems is clustered together by truncating mutually adjacent edges of mirrors and correcting lenses which comprise individual Schmidt systems. By clustering individual systems together, keystone distortion is minimized.

Abstract: A transistor audio amplifier of the Class AB complementary symmetry type is biased with a new bias circuit to keep both transistors on during all normal signal conditions. The bias circuit includes a pair of series connected V.sub.BE Multipliers with an interconnection between the two multipliers receiving signal feedback from the amplifier output such that the Multipliers can bias both complementary transistors on for all normal signal operating conditions.

Abstract: A two branch circuit for converting dual complementary signals characterizing emitter coupled logic to a single signal characterizing transitor-transistor logic. A two branch circuit supplies translation between ECL input signals, referenced to a voltage supply and TTL output signals, referenced to ground, using a current summing node receiving current from both branches and connected to a TTL output driver. A first circuit branch includes a feedback loop which generates a reference current summed with the current in the second branch.

Abstract: An apparatus for straightening ductile wire leads, as in an integrated circuit container of the T.O. type. The apparatus includes a seat for holding the base of a T.O. device, with leads projecting away from the base. A number of hooks are thrust inwardly by a motive means toward the leads, engaging the leads, and pulling them to a radially outward position. With the leads held in this position, the base of the T.O. device is lifted by another motive means thereby causing the leads to be pulled through respective hooks. The ductile leads are straightened as they are pulled through the hooks.