Abstract: A channel identifying rolling bar code, transmitted with a television broadcast signal, is displayed at a selected location on the receiving television screen. An apparatus is secured to the television set to view the rolling bar code to identify the channel being transmitted and process that information as necessary to detect the periods of time that different channels are received by the particular set. That information is stored in an internal memory for eventual use by a central processor.

Abstract: A cable meter for monitoring the channel selected by a converter of a television system which receives signals by means of cable. The cable is connected to the cable meter and the output of the cable meter is applied to the converter. The output of the converter is connected back to the cable meter which, in turn, provides an output to the television. During normal operation, signals received by the cable meter from the cable pass directly to the converter, and a selected channel from the converter passes through the cable meter to the television. To monitor the channel selected, an oscillator generates a substitution signal which is substituted for the television signal applied to the converter. The cable meter then monitors whether the substitution signal passes through the converter, during which period, the cable meter prohibits this substitution signal from reaching the television. By varying the frequency of the substitution signal, a search is performed for the selected channel.

Abstract: A demand driven access mechanism comprises logic apparatus at each station capable of seizing use of the shared communication channel for enabling access by a selected single station. The logic apparatus receives status signals from all stations so that if one station seeks access to the channel it will be enabled. If two or more stations simultaneously seek access to the channel, the logic apparatus establishes a priority order between them, thereby enabling access to only one station at a time. The stations time-share the channel so that relatively slow stations may make more effective use of the relatively fast communication channel.

Abstract: A one piece carrier for flatpack chips capable of accommodating chips of varying size. The carrier includes a pair of cantilever arms each having a tapered head for holding chips of varying thicknesses. The arms extend into the carrier's central aperture, one from the top and one from the bottom side of the aperture. Longitudinally offset stops are mounted on the arms to both laterally and longitudinally stabilize a small chip whose length is insufficient to reach the conventional stops mounted on the top and bottom sides of the central aperture. A recess is provided in the lateral sides of the central aperture to accommodate motion of the cantilever arms so that chips of varying widths may be held between the heads of the arms up to the width of the central aperture. A step of lower elevation is formed in the body of the carrier between the lead support channels adjacent the lateral sides of the central aperture to accommodate the formed leads of a chip.

Abstract: In a first searching mode of the control program for the microprocessor, the microprocessor starts with a selected clock input and associated delay circuit and sets the delay circuit to an initial clocking point which is intermediate to the minimum and maximum delay points. The microprocessor then, at each pass of the control program, successively increments the delay period interposed by the delay circuit to cause the clock pulse to arrive later and later in time at the clock input until the associated circuit fails, to indicate the late clocking failure limit. In the second searching mode of the microprocessor control program, the microprocessor starts at the late clocking failure limit and at each subsequent pass of the program successively decrements the delay period interposed by the delay circuit to cause the clock signal to arrive earlier and earlier in time until the semiconductor device fails again, to indicate the early clocking failure limit.

Abstract: In an electron beam lithography apparatus a capacitance height gauge is used to determine the distance between a reticule and electron optics. In order to calibrate the capacitance gauge an optical interferometer, including a mirror are mounted on the same axis as the capacitance gauge. The mirror is moved a predetermined distance so that the movement distance measured by the capacitance gauge and the interferometer can be compared.

Abstract: A method of calibrating a capacitance height gage for an electron beam lithography machine. The electron beam apparatus having the capacitance height gage to be calibrated is first mounted in a calibration fixture wherein the distance between the gage and a calibration reticle is adjusted using a laser interferometer. The electron beam is directed to a center high backscatter point, and then deflected to a predetermined high backscatter point. The capacitance gage readings and deflection voltages are measured to define a calibration plane. The electron beam apparatus is then repositioned to the lithography station having a reticle positioned below the electron beam. The distance to the reticle is measured with the capacitance gage, and the deflection of the electron beam during lithography operations is adjusted according to the variation of the reticle plane from the calibration plane.

Abstract: In a bubble memory package, a contoured, shaped magnet and filler plate combination is provided to shape the magnetic field in a uniform fashion to prevent the loss of magnetic flux density which normally tends to occur in the center of the magnet area of a planar, uniformly thick magnet.

Abstract: A computer cooling system has a mixing valve which supplies coolant to the computer and receives hot return coolant from the computer and also chilled return coolant from a chiller intermediate the computer and the mixing valve. The mixing valve mixes the hot return coolant with the chilled return coolant to adjust the cooling system temperature. Control circuitry senses, or estimates, the dew point temperature of the computer room environment, compares it with the cooling system temperature, and adjusts the mixing valve to maintain the cooling system temperature a few degrees above the dew point temperature. A condensation sensor comprised of a light emitting diode (LED), reflective tape applied about a cooling system supply conduit, and a phototransistor is disclosed. Light from the LED is fully reflected by the reflective tape to the phototransistor in dry conditions, but only partially reflected when condensation forms on the tape.

Abstract: A hardware network or system is disclosed for testing LSI and VLSI logic device design and system design by simulation utilizing individual gate functions. The simulator system uses switching logic, random access memory, and a state table device to simulate particular test routines to test device design with functions which may appear in random or semi-random sequence.

Abstract: Connector assemblies are provided for mounting leadless chip carriers to a printed wiring board (PWB). Each connector assembly includes an elongate rigid and electrically insulative body, and electrically conductive leads. The body has two rows of pockets, each containing a lead. Each lead has two widened contact sectors. The shape of the lead is such that with one end mounted in the PWB, the sectors are opposite one another and approximately the same distance from the PWB. Each connector assembly is mounted by soldering the body to the PWB and mounting one end of each lead to the PWB. Each pocket has a channel narrower than the sector and wider than the general lead width, to restrain its associated lead to flexing movement in one direction transverse to the body. The sectors are offset in this transverse direction from the lead end mounted to the PWB, but in different amounts, thus to enable a staggered positioning of adjacent leads.

Abstract: This amplifier circuit for a magnetic transducer such as a magnetic head includes a pair of transistors which function both as write current modulators and read signal preamplifiers. The transistors are suitable for in situ deposition on a magnetic transducer carrier adjacent the winding, which keeps the signal lines of the data read by the transducer very short until amplification.

Abstract: A solder/desolder tool has a heater block supporting a handle at its upper end and a heating plate at its lower end. The heating plate is thermally engaged by heating elements housed in the heater block. An array of pin relief apertures are formed in the heating plate. Retractable clamps are pivoted to the heater block for clamping a leadless chip against the heating plate. The leadless chip has an array of input/output sockets corresponding to the array of pin relief apertures. A method is disclosed for soldering the chip sockets to a corresponding array of pins supported by a PC board. According to the method, solder balls are loaded in the chip sockets, and the chip is then secured in the tool to reflow the solder balls to form solder plugs. The solder plugs are then set upon the upper ends of the pins and melted by the heating plate so that solder joints are formed between the pins and sockets. The chip is released from the tool to allow the solder joints to cool.

Abstract: The invention comprises a high vacuum compatible electron beam stage having an X/Y and theta coordinate positioning drive mechanism mounted from below the stage. The stage comprises four plates: A base plate, an X plate slidably mounted thereon and constrained to slide in an X direction, a Y plate slidably mounted on the X plate and constrained to slide in a Y direction, and a theta plate mounted on the Y plate and constrained to translate in the Z direction. Two rotary capstans, mounted on drive shafts, are coupled on each to the X and Y plates by a metallic band looped around the capstan and attached at opposite ends to the plate. Rotation of the capstan causes the respective plates to slide in their constrained direction. The theta plate drive shaft is limited to vertical motion. The Y and theta drive shafts couple to universal joints. All three drive shafts couple to bellows joints. This permits the drive shafts to deflect at small angles.

Abstract: A computer cooling system has a mixing valve which supplies coolant to the computer and receives hot return coolant from the computer and also chilled return coolant from a chiller intermediate the computer and the mixing valve. The mixing valve mixes the hot return coolant with the chilled return coolant to adjust the cooling system temperature. Control circuitry senses, or estimates, the dew point temperature of the computer room environment, compares it with the cooling system temperature, and adjusts the mixing valve to maintain the cooling system temperature a few degrees above the dew point temperature. A condensation sensor comprises of a light emitting diode (LED), reflective tape applied about a cooling system supply conduit, and a phototransistor is disclosed. Light from the LED is fully reflected by the reflective tape to the phototransistor in dry conditions, but only partially reflected when condensation forms on the tape.

Abstract: A logic system maintains current least recently used information among the elements of each group in a plurality of groups where each group includes two or more elements. A memory stores intermediate information regarding the relative precedence between each combination of elements in a given group. A logic network recomputes this value each time an element in a group is used and provides this new information to the memory and to a network which resolves the current least recently used status.

Abstract: A connector assembly comprises a male and a female connector, the male connector having releasable lock means on its shank. The lock means includes a plurality of radially extending tongues extending outwardly from such shank, the tongues being compressible to fit within the bore of the female connector during assembly and disassembly of the connectors. The female connector includes a recess or chamber in the bore for receiving the tongues to lock the connectors together, and a flange against which the tongues may react to enable compression of the tongues an disassembly of the connectors.

Abstract: A method for producing an NPN semiconductor device which has a titanium-tungsten barrier metal only in the N type contact windows is disclosed. A semiconductor wafer first undergoes the washed emitter process with the result that the N type collector and emitter contact windows are exposed to bare silicon and the P type contact windows are covered by a layer of silicon dioxide. A layer of titanium-tungsten alloy is deposited on the surface of the wafer. The titanium-tungsten layer is etched out of the P type contact regions using standard photolithographic techniques. The underlying layer of silicon dioxide in the P type contact regions is then also etched away. A layer of aluminum is then deposited across the surface of the wafer. The conductor interconnect photolithography is used to etch away all undesired aluminum. The remaining portions of the titanium-tungsten layer, not covered by aluminum signal lines, are then also etched away.

Abstract: A quartz lamp heater is disclosed for a combined microwave, infrared and convection cooking oven. The quartz infrared lamps have blinds which either direct the infrared rays toward the food for broiling, or towards a rotating heat exchanger/fan, which in turn transfers heat to the air and blows it out and down towards the food. A quarterwave choke is provided to prevent microwaves from exiting the cavity through the power leads to the quartz lamp heaters.

Abstract: A digital motor speed control for a disk drive which is speed regulated by servo data retrieved from the disk drive's servo disk.