Abstract: There is provided a single-tank X-ray unit having a closed cooling circuit arranged in a housing for circulating a cooling agent to discharge the heat generated in the anode. The cooling circuit includes a feed duct and a return duct respectively wound helically around the high-voltage generator. A fan is so positioned in the housing as to pass cooling air over the cooling circuit, the housing having openings respectively for the intake of the cooling air and the discharge of the same.

Abstract: A silicon controlled rectifier (SCR) lamp supply trigger circuit, responsive to control circuitry, produces trigger currents for the SCR which transmits the required voltage to illumination lamps in a document image capturing system. The trigger circuit includes a single AC input supply voltage having a positive and negative portion and electronic components for accumulating the respective voltage portions and isolating them to avoid unwanted signal interference with the control circuitry regulating the lamp supply voltage. Devices discharge the voltage accumulating components in response to the control circuitry of the SCR lamp supply and feed the discharged voltage to an apparatus for conversion to a current for triggering the SCR. Residual voltages remaining on the voltage accumulating components are automatically discharged during that portion of the AC input supply voltage which is opposite to the polarity of the charges stored on the voltage accumulating components.

Abstract: An inverter for diagnostic X-ray equipment, comprising a thyristor bridge with an input diagonal connected in series with two commutating inductances across a DC power supply, is provided with a start-stop circuit which includes an ancillary thyristor connected in series with a diode and a current-limiting impedance across one of the bridge arms. On start-up, the ancillary thyristor is triggered simultaneously with the diagonally opposite bridge thyristor in order to connect the current-limiting impedance in series with the AC output diagonal of the bridge during the first half-period; for a quick cutoff, the ancillary thyristor and the associated bridge thyristor are turned on together whereby two previously charged quenching capacitors, one of them included in the start-stop circuit, are discharged through the commutating inductance in series with the associated bridge arm to terminate conduction in another bridge arm fed through the same commutating inductance.

Abstract: In the illustrated embodiment, a compression plate is support-mounted parallel to the breast support plate, and is adjustable relative to the breast support plate for the purpose of adjusting its spatial interval from the breast support plate. The compression plate has a cut-out section (12) of such a size that a larger portion of the breast is left exposed. At the margin of the cut-out section there is a marking (13, 14), reproducible on an X-ray film, for the purpose of locating a specific point in the cut-out section.

Abstract: A body is irradiated by a primary radiation beam; the scattered radiation produced thereby is incident on a detector device consisting of a plurality of detectors and is a measure for the density distribution of materials in the primary beam. However, this gives rise to multiple scattered radiation which disturbs the measurement. The present invention provides a device in which disturbance by multiple scattered radiation is greatly reduced, without any significant effect on the scattered radiation originating from the primary beam. A device in accordance with the invention is provided with flat laminations which are arranged between the primary beam and the detector device and which are aligned with the primary beam in a fan of flat planes.

Abstract: The invention provides a two-terminal flasher device, particularly for flashing automobile lamps, that can replace the thermal devices predominantly currently in use. An electro-mechanical relay is used to flash the lamps, while an electronic circuit controls the flashing rate. The power for operating the relay and the electronic circuit is maintained by means of a capacitor that is charged from the power source (the battery) and then discharged while the power source is not available, the electronic circuit being supplied from the capacitor via a constant voltage source. Preferably the charging of the capacitor is arranged so as to give an "instant-on" type of operation. The lamp current is measured by a voltage measuring means including a resistor formed by part of the copper of the board on which the circuit is mounted, and the temperature coefficient of the circuit is arranged to be as close as possible to that of the copper.

Abstract: Methods and apparatus for electronically igniting gas discharge lamps, such as hot- or cold-cathode fluorescent lamps, various high-pressure, metal-gas, and halogen-gas lamps.The initial heater current, in the case of hot-cathode lamps, or the initial high voltage across the unignited lamp, in the case of cold-cathode lamps, is used to heat a positive temperature coefficient resistor. The heat generated by this resistor causes a striker mechanism, consisting in essence of a pre-tensioned bi-metal disc or strip, to buckle, the said buckling striking a piezo-electric crystal, thereby inducing a high voltage, which ignites the lamp.Various coupling circuits between the mechanism and the lamp are described.The important features, compared to presently known igniters relate to the flickerless and reliable ignition of the lamp, more reliable igniter structure, and lengthened life time of the lamps.

Abstract: A fixed interval, variable period technique for measuring pulse rate including defining the start and the end of a fixed measuring interval, counting the pulses whose rate is to be measured beginning in response to the start of the measuring interval and stopping in response to the end of the measuring interval; measuring the period of time between the occurrence of the first counted pulse and the last counted pulse; and dividing the number of pulses counted during a measuring period by the period to determine the pulse rate.

Abstract: An apparatus for heating the cathode of an electronic power tube, having a supply for delivering a heating current to the cathode, an interrupter circuit for periodically interrupting the flow of heating current to the cathode, and controls for controlling the duration of these periodic interruptions and for regulating the net amount of heating current. To achieve this, the controls include a voltage control that varies in such a way so as to bring the heating current from a value of O to Io (where Io is the correct heating current at which the tube will be in a pre-heated condition) during a first, predetermined time period, and then from a current Io to a current Im (where Im is the optimum value for the heating current when the tube is normally operating), during a second predetermined time period.

Abstract: In an illustrative embodiment, body zone selector keys are associated with a visual representation of the human body. When a body zone key is actuated, the available exposure programs for specific organs or body portions in the selected body zone are displayed on respective indicator panels having respective adjacent operating keys. For the case of seven zone keys and seven operating keys, an electronic fixed value store (e.g. a PROM) may contain seven sets of storage locations, each set containing data for controlling the alphanumeric displays at the seven indicator panels to indicate available exposure programs related to one body zone. For example, there may be twelve matrices formed of LEDs in each indicator panel for display of twelve alphanumeric characters to designate the organs or body portions indicative of the seven different exposure programs currently available for selection.

Abstract: A flow, or rotary type, microfilm recording apparatus for filming documents having a document transport means to move documents past an aperture area. An alternating current powered fluorescent lamp is employed for illuminating the documents in the aperture area. In order to adjust, set and maintain a substantially constant level of illumination in the aperture area and to reduce flicker, a lamp regulator circuit is provided which includes a shunted rectifier load circuit and a variable current device responsive to the illumination from the fluorescent lamp for varying the voltage drop across the shunt in accordance with the illumination.

Abstract: A tuning device including a conductive housing in which are suspended a dielectric substrate. A pair of first and second resonant circuits is disposed on the substrate in parallel with each other. Each resonant circuit is formed by an elongated conductive film and a capacitive element. A grounded conductive strip film is provided between the transmission lines of the first and second resonant circuits to reduce the interstage coupling between the two transmission lines with a resultant decrease in spacing between them.

Abstract: An apparatus and method is described for producing an electric field distribution in an imaging chamber corresponding with that of spherical caps.By adequately choosing the distance between annular ring electrodes provided on or in the electrodes of the imaging chamber, use may be made of a high DC-voltage generator of the cascade type so that the voltage applied to each annular electrode is an integer of a basic voltage. Also the voltage over the gap may so be generated.As a consequence, only one high DC-voltage is necessary for generating all the voltages of the whole system.

Abstract: This invention relates to a spectrograph-monochromator of grazing incidence type which is particularly but not exclusively designed for examining soft x-ray and ultraviolet radiation. the spectrograph-monochromator according to the invention comprises an inlet slit, a reflecting diffraction grating and a detector comprising a photographic plate for spectrographic recording or, alternatively, an outlet slit for selecting a single monochromatic component, the improvement being that the inlet slit is disposed in a fixed position relative to a base plate, provided with an openable cover and said grating and said detector are disposed longitudinally displaceable on a curved guide, which represents a portion of a Rouland circle and is rotatable about an axis coinciding with that of said inlet slit.

Abstract: A gas discharge display apparatus including a gas discharge display panel comprising a plurality of cells arranged in a column/row matrix. Cathodes are connected to the rows and anodes to the columns of the matrix. The cells are arranged in repeating groups each comprising at least two columns. Corresponding cells in each group are primed contemporaneously in a desired sequence whereby the last cell in the sequence to be primed is adjacent the first cell in the sequence to be scanned. In priming the cells each cell is discharged at a low level. Various types of priming loop sequences are disclosed.

Abstract: An electric light controller which serves to connect and disconnect an electric lamp element load from a power source in such rapid-fire pseudorandom seuentiality that the electric lamp appears to the eye as an illusion simulating the fluctuant brightness variations inherent in a flickering flame produced light. The result is an improved specious effect for decorative items such as electric lanterns used for outdoor lighting, simulated burning fireplace log arrangements, decorative chandeliers, holiday lighting equipment such as Christmas tree lights, and other such devices. Further enhancement of realism of the produced effect is provided for "open fire" decorative apparatus, such as electric fireplace log arrangements, through the optional inclusion of a popping acoustical sound translator, excited by a pseudorandom audio signal, which serves to simulate the crackling sound made by a burning material.

Abstract: An electronic solid state system is provided for starting and operating one or more fluorescent lamps, and which supplies power to the lamps at a relatively high frequency, and at a relatively high power factor. The system includes a circuit which forces the line current to be proportional to the applied input voltage so as to maintain high power factor concomitantly with the removal of flicker by high frequency operation. High power efficiency is achieved through the use of a switching resonant inverter output circuit which is ideally suited to fluorescent lamp applications because of its low harmonic energy content, and because it can accommodate a wide range of resistive loads at high efficiency. The system may also incorporate a dimming circuit for the fluorescent lamps.

Abstract: A method and a circuit arrangement for time stabilization of scanning pulses for the stroboscopic sampling of periodically recurring signals. Stroboscopic sampling is performed by means of scanning pulses having a repetition period slightly different from the period of the recurring signals to be scanned. The signals to be scanned are transmitted over a transmission line in which a measuring section of known length is defined by the distance between two tapping points to each of which a sampling circuit is connected. The signals transmitted over the transmission line are sampled stroboscopically by means of the scanning pulses whereby time-transformed signals are obtained. These time-transformed signals are separated by a time interval corresponding to the transit time of the signals in the measuring section multiplied by the time-transformation factor.

Abstract: The patient's breast is pressed against an X-ray film vacuum cassette inserted into a holding arrangement mounted on the X-ray exposure-taking machine. With the patient in position, the technician can remove and insert cassettes from the side, without requiring the patient to move back away from the cassette holding arrangement as with prior-art holding arrangements. Two opposite ends of the loading platform of the holding arrangement are each provided with two holding brackets mounted slidable towards and away from the respective ends of the loading platform, but spring-biased towards the respective ends of the loading platform.

Abstract: In connection with radiographic inspection of structural and industrial materials, method and apparatus are disclosed for automatically determining and displaying the time required to expose a radiographic film, positioned to receive radiation passed by a test specimen, so that the finished film is exposed to an optimum blackening (density) for maximum film contrast. A plot is made of the variations in a total exposure parameter (representing the product of detected radiation rate and time needed to cause optimum film blackening) as a function of the voltage level applied to an X-ray tube. An electronic function generator storing the shape of this plot is incorporated into an exposure monitoring apparatus, such that for a selected tube voltage setting, the function generator produces an electrical analog signal of the corresponding exposure parameter.