Abstract: A high-pressure discharge lamp having a hydrogen getter in a metal envelope of which only a part consists of a hydrogen-permeable metal. The getter is arranged in the lamp in such manner that the hydrogen-permeable part of the envelope faces the discharge.

Abstract: The circuit includes sources of periodic, low duty cycle, load terminal energizing and control terminal driving pulse waveforms. During each cycle, the waveforms occur only during successive test intervals occupying only a small portion of each cycle. During each test interval a load terminal energizing pulse is generated to energize a transistor or FET device of a different conductivity type and a control terminal drive voltage is penetrated which initially is of a polarity which would render a transistor or FET device of the associated conductivity type non-conductive, and then switches to a voltage of opposite polarity to render such device fully conductive. There is provided means for selectively varying the control terminal driving current which flows in an operating device from a relatively high to a relatively low level. Signals are derived showing the transition in the conductive states of the devices under test during the polarity transition of the control terminal drive voltage waveform.

Abstract: In rotary anodes which are journalled on two sides a problem occurs, notably as regards the bearing which is arranged on the side of the anode disc which is remote from the rotor. The problem involves excessive discharge of heat via the shaft and the bearing. A possibility of reducing the quantity of heat applied to the bearing consists in the increasing of the length of the anode shaft to increase the heat resistance. However, the length of the X-ray tube is then also increased. The invention provides a combination of smaller length, substantially free choice of the material of the anode shaft and hence overcritical speeds for the tube during operation by forming the anode shaft as a hollow rotor shaft coupled to the anode disc and a further shaft journalled at both ends to the respective bearings and connected to the hollow shaft.

Abstract: A readout device connected to a parent metering system contains a digital display for circumventing the non-linearity of analog meter movement in the parent system. The readout device displays both numerical and dimensional information in a clear, legible form with both probe and range scale factors accounted for in the display itself. A "probe" switch on the front panel of the module encodes the logarithm of the scale factor associated with the probe in use to a two's complement binary number, and the full scale range information from the "range" switch is encoded in the same manner. This information, along with function information from the "function" switch, is processed by a scale computation circuit which positions the decimal point and causes the units of measurement to be indicated accordingly.

Abstract: A current detecting apparatus wherein when a wire is energized, a reed switch comes into operation in response to the magnetic lines of force generated concentrically around the wire to detect the presence of a current flow in the wire. The current detecting apparatus may be easily attached on and removed from a wire.

Abstract: A probe station having a cryogenic container preferably situated in a vacuum chamber. Semiconductor devices to be tested are attached to the container of cryogenic liquid. Electrical contact to the devices is made using contact wires which are moved by manipulators lying outside the vacuum chamber. Integrity of the vacuum at the manipulators is assured by using bellows to allow for the movement of the contact wires. Visual placement of the contact wires on the devices to be tested is accomplished with the aid of a microscope external to the vacuum. One end of the vacuum chamber is made of clear plastic to be used as the microscope viewing window. A spring is used external to the vacuum space to counteract the effects of atmospheric pressure on the movable bellows. The semiconductor devices are then tested by the connection of the appropriate test equipment to the electrical contact wires.

Abstract: Compact oscilloscope in which the display, an array of light emitting diodes, is integral with the probe. The array continuously is scanned column by column at a controllable rate and concurrently voltages are applied to rows selected in accordance with the amplitude of the test waveform. Light is emitted from those diodes of the array receiving coincident row and column excitation to thereby display the test waveform.

Abstract: The present invention provides method and apparatus for testing a network, such as a printed circuit board, to check whether it conforms to its design as to having a plurality of network nodes and a predetermined node-connection pattern defining a division of the network nodes into a plurality of groups. In a conforming network, each network node is connected in common to all other network nodes in its group, and is isolated from the network nodes in each other group. In accordance with the invention, one of the network nodes is selected to serve initially as a present FROM node. There is thereafter selected repeatedly, from the network nodes that have not previously served as a present FROM node, a network node to serve temporarily as a present FROM node.

Abstract: A digital voltmeter for measuring an input voltage which can lie in any one of M successive ranges comprises an input scaling device which scales the input voltage to produce a voltage lying in a single predetermined range, and which also produces a range signal indicative of the range in which the input voltage lies. An analogue-to-digital conversion circuit then converts the scaled voltage to a corresponding digital signal which has up to N significant decade figures of resolution, where N<M. The voltmeter has a display unit with M decades, each of which represents a fixed order of magnitude of the input voltage, and control means responsive to the range signal to direct the digital signal to the group of N adjacent decades of the display means appropriate to the magnitude of the input voltage.

Abstract: An ion counter for measuring the density of atmospheric ions has two basic sections, the electrometer, which is of a conventional type, and the collector. An improved collector is provided having two collector plates in electrical contact, mounted either side of a polarizing plate to form a double channel cell having two air passages. The polarizing plate and the collector plates are tightly secured to insulators so as accurately to maintain the spacing between the plates.

Abstract: A method of testing semiconductor devices at low temperatures comprises the steps of first directing a relatively cold fluid upon the device for a time long enough to reduce the temperature thereof below the temperature at which it is to be tested, then internally heating the device to the test temperature and then performing a test at the testing temperature.

Abstract: A method for the nondestructive testing of voltage limiting blocks includes the steps of providing several discrete electrical contacts across the block, sequentially applying to each of the contacts a voltage to determine the corresponding current and utilizing the current and voltage values to determine constants related to the microstructure of that particular location. The constants can then be utilized to derive a contour map which will be indicative of a hot spot in such block as determined by a maxima of the contour map.

Abstract: Circuit board testing apparatus featuring an improved weighting assembly for holding a circuit board in contact with test pins.

Abstract: A test probe apparatus having a housing movable into engagement with a printed circuit device connected to a circuit board with a plurality of electrical contact members extending at various angles to the circuit board, and a plurality of contact probes mounted by said housing for engaging each of said contact members with a constant force insufficient to damage their connection to the circuit device, and a mounting device for holding the housing in engagement with the circuit device while attached to the printed circuit board.

Abstract: The position or presence of a metallic object is detected by an electronic circuit which senses a shift in phase between a first cyclic signal and a second cyclic signal which shifts in phase in response to movement of the object. An oscillator produces the first cyclic signal which is used as the reference signal and as the excitation for a parallel resonant circuit which produces the second signal. The phase of the second signal is shifted in response to movement of a metal plate or a shorted coil in an electromagnetic field produced by an inductor in the resonant circuit. The degree of the phase shifts may be used to detect the position of an object in the electromagnetic field or rate of the phase shifts may be used to detect the velocity of an object. An exclusive-or gate senses the changes or differences in phase between the two cyclic signals and produces an output signal representative of the changes or differences in phase.

Abstract: A spark plug for internal combustion engines having a center electrode, a ceramic insulator body and metal sleeve around the body. The sleeve defines an annular outside electrode around the center electrode with a concave depression in the insulator between the electrodes. The plug is operated at high current and voltage so that a high intensity spark will burn off any combustion residue on the relatively small insulator area between the electrodes. A process for removing combustion residues using this spark plug is also disclosed.

Abstract: An a.c. input signal is supplied to at least one input terminal to which at least one rectifier is connected for converting the a.c. input signal to a d.c. signal corresponding thereto. A plurality of transistors are connected between the at least one rectifier and a general purpose integrated circuit with a threshold value. Each of plural transistors is controlled in its on/off operation by the d.c. signal from the rectifier in order to control the output potential of the integrated circuit. A plurality of indicators are connected between a d.c. power source and outputs of the integrated circuit to be discretely and sequentially energized to indicate a peak level of the a.c. input signal.

Abstract: A high pressure sodium vapor discharge lamp comprises an alumina tube envelope containing therein sodium, inert starting gas, buffer gas source of mercury or cadmium and discharge electrodes sealed in the envelope, inner diameter d (in mm) of said tube envelope and an average potential gradient E in volt/cm having the relationE.gtoreq.37.7-2.05d,and further comprisesA radiation suppressing means for selectively absorbing red radiation of a wavelength longer than 620 nm said radiation suppression means being disposed on the wall of outer bulb enclosing the tube envelope;The lamp achieves higher color temperature and higher general color rendering index than the conventional one without increasing its tube voltage and is suitable for highly efficient indoor illumination.

Abstract: An X-ray generator comprising a shielded housing having insulatingly mounted therein an X-ray tube provided with a predetermined focal spot area on a sloped target surface which is radially aligned with an X-ray transmissive window in the housing, the window having a preferred configuration for reducing preferential absorption of X-rays in a divergent beam emanating from the focal spot area of the target.

Abstract: An X-ray generating tube is disclosed, which tube is especially suitable for use in a computerised tomographic apparatus in which a spread of x-radiation is required to shift rapidly relative to the body of a patient under examination. The tube contains a rotating anode which is either reciprocated to-and-fro along the axis of rotation thereof or contains a shaped profile which scans along said axis.