Abstract: The invention relates to a radio therapy apparatus comprising an electron accelerator having a target and a collimator for limiting the X-ray cone. In the use of such electron accelerators, the radiation load of the patient is increased in an undesirable manner by neutrons in addition to the therapeutically desired roentgen quanta. To reduce the neutron level the invention provides that the edge zone of the collimator facing the target is made of a material of low effective cross-section for (gamma, n) processes. The dimension of this edge zone material approximately corresponds to the half-value depth of the X radiation in this material.

Abstract: A read circuit for a floppy disk drive is disclosed. The circuit comprises a read head for generating an electrical signal corresponding to recorded data, plus an amplifier, equalizing filter, low pass filter and decoder for processing the electrical signal.

Abstract: A DC power supply having an input stage receiving input power at one voltage and an output stage connected to the input stage producing output power at another, output voltage. The output stage receives a control signal reducing the output voltage by a prescribed amount when the output current exceeds a given level. The control unit includes a comparator which compares the output current with a reference level and produces a current foldback signal if the output current exceeds the reference level.

Abstract: There is disclosed a high power and/or high voltage switching operational amplifier arrangement having a comparator with a first input for a low frequency AC signal. The output of the comparator is connected with the data input of a bistable element. The bistable element is triggered by a clock pulse signal with a rate substantially higher than the frequency of the AC input signal. An amplifying stage arranged between both poles of a high power and/or high voltage source is composed of a pair of alternately operating switch means, each arranged between a respective pole of the voltage source and a common amplifier stage output. Each of the switch means is coupled by a control input to at least one of the outputs of the bistable element. A low pass filter network coupled to the amplifier stage output forms the output stage of the operational amplifier arrangement. Means for providing feedback are arranged between the filter network and a second input of the comparator.

Abstract: The electron exit window assembly contains a metal cover plate, a titanium insert piece and a titanium exit window. The cover plate covers the interior of the last cavity of the accelerator. It contains an insert opening into which is inserted the insert piece in a vacuum tight manner. The insert piece in turn contains a hole which is covered by the exit window. The cover plate preferably is made of stainless steel, and the insert piece is preferably brazed into the insert opening of the cover plate.

Abstract: The bipolar permanent field interior rotor for an electric machine comprises a multi-sided shaft which can be rotated about an axis of rotation, a multitude of sheet metal disks disposed on the multi-sided shaft, and a number of permanent magnet slabs. Each disk has a central hole formed by central edges and consists of at least two segments. The number of magnet slabs is smaller than the number of shaft sides. The magnet slabs directly engage respectively the sides of the shaft. The remainder of the shaft sides are engaged by central edges of the disks. The axes of magnetization of the slabs are arranged radially with respect to the axis of rotation of the shaft.

Abstract: The bundle of laminations in an electric generator as motor contains a plurality of lamination stacks arranged in series in an axial direction and a plurality of slots in which are arranged the conductors of the machine winding. In order to improve the dissipation of the heat losses from the bundle of laminations and the winding, laminations are contained in the stacks which have a slot width greater than the width of the conductors and which have on the slot floor a recess of a greater depth. Thus side ducts are formed alongside the conductor which are in connection with the air gap of the machine, and axial cooling channels are formed on the slot floor which open at least on one side into a radial cooling channel. By reversible packing of these laminations, the position of the lateral channels can be altered.

Abstract: A solid geometrical puzzle comprises a plurality of basic components each of which is hinged along two edges to neighboring components. A typical basic component comprises a solid element that is triangular in cross section, said triangle being a right angle isosceles triangle. The solid element has three four-sided faces, a lower face, an upper face extending 90.degree. to the lower face and a face joining the free ends of the upper and lower faces. The end portions of the element are triangles. The assembly may be folded along the hinge lines of a particular type to form many regular and irregular geometric shapes such as sawtooth configurations, parallelpipeds etc. The arrangement is intriguing and interesting to work with as a form of amusement and special effects may be obtained by printing designs on the faces.

Abstract: A method and apparatus are disclosed for correcting energy (Z) signal non-uniformities in the response of an Anger-type scintillation camera to image events occurring at different (X, Y) positions on the camera face. Energy correction factors f(P)' corresponding to deviations of up to .+-.12.8% from a reference pixel area are determined off-line for 4,096 camera face pixel areas from a uniform flood field source Z-map. The correction factors f(P)' are stored in a 64.times.64 array of a correction factor memory, addressable by image event (X, Y) position coordinates. During on-line operation, for each image event the correction factor f(P)' corresponding to the image event (X, Y) position is retrieved, scaled in a multiplying digital to analog converter by the actual energy Z.sub.IN of the event, and added to the event Z.sub.IN signal to provide a corrected energy signal Z.sub.c =Z.sub.IN (1+f(P)') which is proportional to the incoming signal.

Abstract: There is disclosed a conversion circuit arrangement for switching digital data signals between data terminals operating with different data transmission procedures. The circuit arrangement adapted for use with an electronic data switching system is composed of at least two interface circuits having input/output converting networks. External terminals of these interface circuits are connected to respective input/output means of the switching system for each type of data terminal. Internal input/output terminals of the interface circuits are connected to respective terminals of a storage unit. There is provided a control unit for controlling data transmission between the interface circuits and the storage unit and vice versa such that messages are buffered in the storage unit. The stored message is converted according to the data transmission procedure of the receiving data terminal.

Abstract: The target assembly contains a metal plate which has two end faces, a recess in one of these end faces, a target for generating X-rays when hit by high-energy electrons, and a cooling channel in the metal plate for directing a cooling medium therethrough. The target is arranged in the recess of the metal plate such that the recess is divided into two chambers. The cooling channel passes through these two chambers thereby exposing the target directly to the cooling medium when the latter flows through the cooling channel.

Abstract: A circuit arrangement for determining the connection condition of a plurality of subscriber lines in a telecommunication network, each of the subscriber lines having two wires extending between a subscriber station and a subscriber line interface circuit and being connected via respective resistors to the two poles of a DC voltage source. For a group of such subscriber lines the operating conditions are consecutively monitored by sampling the voltage occurring at two sampling points of both wires by a respective multiplexor and passing it to a comparator having inputs which are temporarily inter-connected by filter capacitors each separately associated with a respective subscriber line interface circuit. In addition, the comparator receives a reference voltage determining a threshold voltage. For ground key indication one of the sampling points is connected to one input of a further comparator which second input is supplied by a corresponding further reference voltage.

Abstract: A method and apparatus for the dynamic modification of the spatial distortion correction capabilities of a scintillation camera having spatial distortion correction apparatus. The spatial distortion correction apparatus includes a memory having stored therein spatial distortion correction factors in a predetermined addressable format. During the on-line use of the scintillation camera, the spatial distortion correction apparatus transforms the image event coordinate position data from the scintillation camera in accordance with the stored distortion correction factors to provide corrected image event coordinate repositioning data. The spatial distortion correction modification apparatus and method provides modification of the corrected image event coordinate data in accordance with the respective energy levels of the image events to provide accurate spatial distortion correction characteristics for the actual energy levels of the image events.

Abstract: An X-ray generator has at least a first and a second cathode filament for emitting electrons, one end of the first filament being connected to one end of the second filament, the connection point forming a terminal. Still two further terminals are located at the ends of the serial connection of the two filaments. Two of the three terminals are connected via a diode in each connection line to the first pole of a d-c source, while the third terminal is coupled to the second pole of the d-c source. Both diodes are oppositely poled. The polarity of the d-c voltage supplied by the d-c source can be changed, for example, by a remote reversing switch. The polarity of the d-c source determines which and how many filaments are energized to provide focal spots of different size. Since two supply lines are sufficient in a high-voltage cable for feeding the first and second filaments, a third line in the cable can be used for the supply of a third heating filament.

Abstract: A floppy disk magnetic information storage and retrieval unit having a magnetic read/write head carriage and apparatus for shifting the carriage radially with respect to the floppy disk to effect data transfer with selectable tracks on the disk. The carriage shifting apparatus includes a lead screw shaft; a carriage nut arranged on the shaft and moveable axially when the shaft is rotated; and a stepper motor having a permanent magnet rotor arranged coaxially with, and rigidly attached to one end of the shaft. Two bearings are provided to hold the shaft and rotor combination at opposite ends of the shaft.

Abstract: The electron applicator incorporates a stationary support tube and an insert tube. The support tube and the insert tube each have a first end portion and a second end portion. The first end portion of the insert tube slideably extends into the second end portion of the support tube. Electrons of high energy are transmitted through the assembly of both tubes. The surface of the insert tube is tapered inwardly toward the end thereof in the travelling direction of the high energy electrons. A device is provided for preventing the insert tube from sliding out of the support tube. A first engaging device engages the insert tube in a first working position. This device is such that upon a predetermined axial force which may inadvertently be exercised by a patient under treatment, the insert tube will slide into the support tube.An adapter for small field or cavetory treatment may be connected to the output end of the insert tube.

Abstract: A temperature controlled oven chamber for gas chromatography incorporates a first stationary chamber wall, a second stationary chamber wall arranged remote from the first wall, and a displaceable chamber wall which is moveable between a closed position and an open position. In the closed position, the displaceable chamber wall forms the casing of the chamber or housing, and surrounds stationary analytical devices. In the open position, the displaceable wall is moved away from the first stationary wall, thereby opening the chamber or housing and yielding access to the analytical devices. When moving from the closed position to the open position, the displaceable wall will enclose the second wall at least temporarily.

Abstract: A method and a circuit arrangement for clock synchronization in the transmission of digital information signals. In the four-wire type transmission of blocks of information signals on a two-wire transmission line it is determined, by phase comparison, whether the first bit in each block of signals (1) falls within a time interval derived from the bit clock signal of the local clock generator; (2) falls within an adjacent time interval or (3) falls within none of such time intervals. Depending upon the results of this comparison, the time relationships are left unchanged, the period of the clock generator is shortened or lengthened one or more times, or a one-time, initial phase equality is established.

Abstract: There is disclosed a hand-held testing device for indicating different values of an electric test voltage. The testing device comprises at least one grip body adapted to be held in the hand and an electric circuit arranged therein. The grip body has a testing tip forming an input connecting point of the electric circuit adapted for receiving a test voltage and has a ground connection. The voltage divider connected between the connecting point and the ground connection has at least two ohmic resistors connected in series via a respective connector tap. Furthermore, the electric circuit has a plurality of display stages, each stage being connected to a respective connector tap of the voltage divider. Each display stage has a two-state amplifying element responsive to the voltage at the respective connector tap and has an optical display element indicating the presence of a given test voltage which is received at the connecting point.