Abstract: A network for connection between an AC power line and a DC power supply to isolate harmonic currents generated by the DC power supply from the AC power supply, the network employing three similar portions each connected between a repective conductor of the (three phase) AC power line and a respective conductor of the DC power supply. Each of the portions includes the series combination of three "reflectors" each having the parallel resonant combination of an inductor and a capacitor. Further, three series resonant inductor-capacitor combinations are employed each connected between a unique pair of the DC power supply conductors.

Abstract: An antenna is employed to receive a (1540 f0) L1 GPS-satellite signal. In addition, a filter, an (RF) amplifier, a harmonic mixer, and a (sole) local oscillator are employed, the combination configured to mix the seventh harmonic of a 192 f0 local oscillator generated signal with the receive satellite signal to down-convert the frequency of the received GPS-satellite signal to a 196 f0 IF frequency. Further, another filter, an (IP) amplifier, and a mixer are employed, the combination configured to mix the fundamental of the 192 f0 local oscillator generated signal with the 196 f0 GPS-satellite signal to down-convert the frequency of the satellite signal to four f0. Finally, yet another filter and an amplifier are employed, the combination configured to filter and amplify the four f0 GPS-satellite signal.

Abstract: A font cartridge has a memory which stores font information for a number of different fonts. The number of different fonts or the total memory size may exceed the maximum memory size or number of fonts which may be accessed by a printer at any one time. A switching function, a switch configuration logic, and a controller, allow a user to access different combinations of font data to the printer such that the total number of font data and memory size available to the printer does not exceed its limit at any one time.

Abstract: A high voltage probe comprises a standard high frequency coaxial cable terminated in its characteristic impedance through most of the high frequency range, and a circuit of resistors and capacitors that provide a fixed division ratio regardless of the input frequency.

Abstract: A MIC package housing that reduces or completely eliminates alumina substrate cracking due to thermal expansion rate differences between the housing and the alumina by using a low-expansion iron-nickel alloy, such as commercially available Carpenter 49, made to ASTM Specification A-753-78 (Alloy 2) and MIL-N-14411B (MR) (Composition 3 and 4). Such a housing places compressive stresses on glass-to-metal seals used in hermetic feedthroughs and the glass is fused and the stresses relieved by a special process of annealing. Manufacturing yields are improved and very large alumina substrates can be used and are attached by hard soldering.

Abstract: For coupling one, or more, gaseous discharge lamps to a high-frequency AC power-source a ballasting (current-limiting) network employs a first capacitor, a second capacitor, and a transformer having a primary winding coupled to the high-frequency AC power-source by the first capacitor and a secondary winding coupled to the gaseous discharge lamp by the second capacitor.

Abstract: An electroluminescent semiconductor device in which the drain of a MOSFET acts as the driver for a manganese doped zinc sulfide electroluminescent layer. The zinc sulfide layer is coated with a layer of metal which prevents the emission of light from the electroluminescent layer except through an aperture extending through the metal layer. Alternatively, the aperture is omitted and laser emission is induced from a semi-reflective end plate positioned on a side of the electroluminescent layer.

Abstract: A serial protocol register and an initialization counter are configured to initialize (program) a RAM array. The register is configured to receive, in serial format, an initial address to be loaded into the counter. Also, the register is configured to receive, in serial format, a series of machine states (data words), each to be stored in the RAM array. In addition, the register is configured to clock the counter following each received machine state. The counter is configured to develop a series of addresses, each for accessing the RAM array to store in the array a corresponding one of the machine states.

Abstract: A method for using an underground mine communication system to effect minewide communication and an intrinsically safe current limiter circuit for insuring that electrical equipment in the system will not cause incendiary conditions. The underground mine communication system comprises a plurality of repeaters and medium frequency radios, including mobile, portable and personal-carried radios, coupled to electrical conductors and natural waveguides existing in the earth by tuned loop antennas. Messages transmitted by the radios are carried to the repeaters by the conductors or coal seam waves. The repeaters amplify, replicate and retransmit the message at two different frequencies for transmission of the message to a surface base station and to other radios in the system. A paging system, which has a separate set of repeaters, is also coupled to the network of electrical conductors and natural waveguides by tuned loop antennas. The paging system alerts miners to contact the surface base station.

Abstract: A disk drive has a side-zero and a side-one analog and digital circuits. The disk drive may write both sides of the disk at the same time and then verify both sides at the same time. A microcontroller is connected to the side-zero and side-one digital circuits. The microcontroller receives the sensor index pulse from the index sensor and then sends a microcontroller index pulse to the side-zero and side-one digital circuits a predetermined period of time after receiving the sensor index pulse. The predetermined period of time is such that after the head is stepped to the next track and achieves a stable position, writing will begin.

Abstract: A method for remotely monitoring conditions such as carbon monoxide or methane gas concentration, longwall roof support pressure, machine parameters or uncut coal, trona or potash layer thickness in a natural resource mining system such as a longwall or continuous mine system. The method utilizes a plurality of sensors connected to low magnetic moment transmitters, e.g. 0.1 ATM.sup.2, or high magnetic moment transmitters, e.g. 2.5 ATM.sup.2, that transmit collected data during multiple short burst transmission periods. Prior to transmission, the data is converted to a digital word format. An algorithm in the transmitter microcomputer ensures that random time intervals exist between data transmission bursts thus preventing a data transmission clash at the central receiver. A microcomputer algorithm in the central receiver protects against data contention caused by simultaneous transmission from several sensors.

Abstract: Medical needle apparatus for transferring fluid includes syringe assemblies for fluid injection and phlebotomy systems for collecting blood samples. A case with an elongated cavity therein has an open end and a relatively closed end from which a hollow needle projects. An operating member fits through the open end of the case into the cavity and controls both fluid transfer and self-destruction of the apparatus after fluid transfer to prevent reuse. Plastic deformable means responsive to pressure on the operating member in a direction toward the needle renders the apparatus non-reusable after fluid transfer either by actuating needle retraction or by increasing the lateral dimension of the operating member to prevent withdrawal. The apparatus is operable with a single hand to transfer fluid and actuate deformable means without re-positioning the hand on the apparatus.

Abstract: For electrostatic-discharge-protection, a first transistor is configured with the transistor channel connected between circuit ground and an associated (input or output) pad. In addition, transistors(s) are included configured to "float" the gate and/or the well of the first transistor when no power supply potential (Vcc) is present and to couple to circuit ground (or the power supply potential) the gate and/or the well of the first transistor when the normal power supply potential (Vcc) is present.

Abstract: A cap mountable on top of a post connects to, holds and supports, a pair of wires. The cap guards sharp edges at the post top to prevent accidental contact with people or livestock. The cap is readily visible as a marker, a reflector or a color coded sign. A portion of the cap fits closely to the upper post while a crown portion projects thereabove and a bill portion projects outwardly therefrom. The crown and bill portions each define a cavity longitudinally aligned for holding a wire adjacent the post. A narrow throat having a least dimension slightly larger than the diameter of the wire to be held extends laterally from the cavity to a flared mouth that further extends and opens in an upwardly direction. A wire can be moved laterally from a position adjacent the flared mouth, through the narrow throat, to a position within the cavity and can be removed therefrom in a reverse manner.

Abstract: A FIFO buffer in accordance with the present invention employs a 1K by eighteen FIFO (A.fwdarw.B) buffer portion to store eighteen-bit words; an eighteen-bit-to-nine-bit multiplexer portion to convert (fold) stored eighteen-bit words into two, nine-bit words; a nine-bit-to-sixteen-bit multiplexer portion to convert (assemble) pairs of nine-bit words into one, eighteen-bit word; a 1K by eighteen FIFO (B.fwdarw.A) buffer portion to store (eighteen-bit) words; eighteen, tri-state, buffers to permit direct communication; a parity generator portion; a parity checking portion; the combination of an A-port access control portion and a programmable flag logic portion to permit connection to a sixteen-bit or a thirty-two-bit microprocessor; and the combination of a B-port access control portion and a hand shake interface control portion to permit connection to an eight-bit microprocessor, a non-direct memory access DMA type peripheral device, or a DMA-type peripheral device.

Abstract: An articulator comprising two U-shaped wire frames joined by hinges and springs. The frames are snapped onto plastic clips cemented to dental casts. The clips allow the casts to be removed and reintroduced in repeatable positions. A slip-joint provides for left and right height adjustment between the dental casts to be adjusted or separated completely.

Abstract: A cylindrical housing has a plurality of seriate slots. A helical cutter is rotatably mounted within the housing. A drive wire passes through the housing and connects with the cutter to provide rotational movement to the cutter. Plaque is caught between the slots and the blades of the rotating cutter, cut away from the arterial wall, ground up and flushed out through a catheter.

Abstract: For use as a substitute for liquid nitrogen cooled energy dispersive x-ray detection in spectrometry, the present invention comprises a cooper cold-finger having a lithium-drifted silicon detector and FET at one end, and a five-stage Peltier cooling stack thermally connected to the fifth stage through copper braid at the other end, an aluminum heat shield surrounding the cold-finger and thermally connected to the fourth stage of the Peltier cooling stack with a copper braid, a plurality of nylon spiders that support the cold finger within the heat shield and isolate them thermally, a stainless steel cap, a plurality of nylon spiders that support the heat shield within the cap and thermally isolates them, a heat sink in thermal communication with the hot end of the cooling stack, a remote water cooling system piped to the heat sink and mechanically isolated from vibrating the silicon detector, an ion pump to create a high-quality vacuum around the silicon detector, a motor drive to adjust the reach of the sili

Abstract: A method of determining the thickness of a layer of material, such as soil, wood, ice or coal, that utilizes a microstrip antenna as a thickness measuring sensor. The sensor is positioned over the layer and a value for a parameter of the antenna such as conductance or resonant frequency is measured. The value is compared to a calibration table of values and the thickness of the layer is determined by interpolation. Alternatively, the value is compared to a control value to initiate a decision process. The decision could be that a layer of ice is building up on a wing of an aircraft or that an explosive device is buried under a layer of soil.