Abstract: The device concerns a waterhose wound around a bobbin, one end of the bobbin being provided with a quick-coupling having the form of a socket made of rubber or soft plastic connectable to water fittings of varying design.

Abstract: The invention concerns a key joint for electric motors. More particularly, in order to obtain simplified assembly of a squirrel-cage rotor having inclined grooves to a shaft, a key joint is provided wherein the key comprises two integrated parts (1) and (2). The first part (1) has the same width and depth as the keyway in the shaft, while the second part (2) is inclined relative to the first part (1) and arranged radially outside of the latter.

Abstract: A demodulator of the type employed in a "zero-IF" system uses a local oscillator for providing quadrature output signals at the center frequency of a received signal to be demodulated. The demodulator has first and second mixers for separately mixing the received signal with the quadrature signals to provide a first and second output signal each in quadrature at the outputs of said mixers. These signals are low pass filtered. The demodulator includes third and fourth mixers with each mixer respectively receiving at an input one of the first and second low pass signals. At another input the mixers receive third and fourth signals. The third and fourth signals are derived from mixing a variable controlled oscillator (VCO) signal with local oscillator quadrature signals the frequency of said is independent of the center frequency of the received signal.

Abstract: The invention refers to a circuit for telephone systems for the transmission of alternating current signals such as voice signals from a subscriber telephone system to a central office, wherein a signal transformer is provided with a by-pass for the direct current running in both wires to the central office. According to the invention a current path is provided by an amplifier inserted between the two wires to the central office. The amplifier is controlled by the dc current from the central office and alternating current provided by the transformer. The resistance of the amplifier changes according to control signals in the form of current supplied. The application of an amplifier as a current path between the two wires of the central office enables maintenance of direct and alternating current in the central office and simultaneous transmission and amplification of voice signals. The transformer need only supply a small part of the analog transmission signal energy.

Abstract: A tone source is located at each telephone set of a private branch exchange (PBX) or a key telephone system. The tone source provides call progress tones and warble ring tone, as well as a feedback tone in response to the depression of telephone set keypad buttons by the user. The signaling to the central system unit is transmitted via a digital link.

Abstract: An electrical foil heating element has a terminal box attached directly to the element. Power leads may be connected to the heating element after it has been installed through sockets in the box. The terminal box is also provided with screwless contacts or push wire connectors.

Abstract: The spatial position of the core of an optical waveguide (1) can be observed exactly in that the optical waveguide is irradiated, in two mutually perpendicular directions, with parallel light, which thereafter passes through each time one rod lens (31, 32) and into a deflecting optical system (8, 9, 10). With the aid of this deflecting optical system it is possible to produce two side-by-side images of the optical waveguide and its core. With the aid of such an arrangement the cores of two optical waveguides to be joined, can be optically aligned with respect to each other in a simple way.

Abstract: For fabricating porous bodies from a glass starting material, particularly in connection with the fabrication of an optical waveguide preform, it is proposed to fill powdery glass starting material under a pre-compaction into a compression mold, and to compress it thereafter. When the porous body to be formed is to have a varying composition in the radial direction, as is necessary with a view to step index optical fibers or optical waveguides having a graded index of the refractive-index profile, then differently composed powdery glass starting materials are filled one at a time, in adjacent coaxial areas, into the compression mold. This is effected with respect to each of the individual areas with the aid of a screw conveyor under a continuous, adjustable pressure and at an adjustable conveying speed.

Abstract: An image intensifier tube and a method of making same are disclosed wherein veiling glare caused by the amplification of off-axis light is reduced. A face plate is formed from a fused assembly of a glass rod having a low reflective, light absorbing layer thereon, a cladding tube and a jacket tube. The fused assembly is then cut into wafer-shaped slices and the ends polished.

Abstract: A millimeter wave integrated circuit (MIC) includes both low power components and high power components, e.g. Gunn diodes, disposed on a common semi-insulating semi-conductor substrate. Each high power component is formed in an active epitaxial layer and is provided with a heat sink comprising a thermally conductive material deposited in an opening in the back of the substrate below the compound. The low power components are isolated by an implanted proton layer.

Abstract: A self-draining pump comprises a pump housing which bounds an impeller chamber having a central axis that is substantially horizontal in a position of use of the pump and an open end facing in one axial direction. An output passage of the pump housing communicates with a radially outward region of the impeller chamber. An impeller is received in the impeller chamber for rotation about the central axis for impelling fluid from a radially inward region toward the radially outward region of the impeller chamber.

Abstract: There is disclosed an encryption apparatus which apparatus functions to raise a large unsigned integer (B) indicative of message data to a large unsigned integer power E, modulo a large unsigned integer M with each of said integers being as large as N bits wherein the resulting large unsigned integer C is adapted for transmission over an insecure communications channel. The apparatus may likewise operate on a received integer C to recover the decrypted message B. The circuitry includes first logic means which is responsive to the large unsigned integer (B) for successively squaring said integer including means for reducing said squared integers successively by a given modulus M to provide at an output a first value indicative of said squared integer as reduced by said given modulus, selectively operated gating means are coupled to said first logic means and operates to receive bits of a given exponent power E.

Abstract: An integrated communication system (e.g., BIGFON) includes the narrow-band telephone network and a superposed video-telephone network. The path search for setting up calls in the telephone network is carried out with the aid of the telephone call numbers. To permit a video-telephone network structure independent of the structure of the telephone network, each subscriber of the video-telephone network must be assigned a separate video-telephone call number for the path search in the broadband network. In order that a subscriber does not have to dial two different numbers to set up a video-telephone call, each exchange (V1, V2) of the communication system includes a mapping circuit (ZS) which establishes for each video-telephone subscriber (TEA, TEB) a correspondence between his or her telephone call number and a video-telephone call number serving to set up calls in the video-telephone network. This video-telephone call number can be called up from the mapping circuit (ZS) via the telephone network (FN).

Abstract: A pump for pumping and mixing of liquids containing suspensions comprises a housing having an impeller rotatable in both directions and a central inlet. The housing is provided with two outlets which are closed alternatively by a ball, depending on the rotation direction of the impeller.

Abstract: A complementary depletion/enhancement mode (CDEM) gallium arsenide circuit utilizes switching pull-up/pull-down circuits to achieve low power consumption, and makes use of gallium arsenide field effect transistors to achieve high speed. High yield depletion mode field effect transistors are used to implement the sometimes complex complementary logic function in a pass gate configuration. Low yield enhancement mode FETs are used in the closely coupled and spaced tracking circuit. Closely spaced enhancement mode FETs are used because of the likelihood of their having closely matched thresholds.

Abstract: The time required for several calibration signals to traverse a signal path (1, 2, 3) is determined and compared with a nominal value. The individual calibration signals have different values for at least one signal parameter. Depending on the results of the comparison, a control signal is produced for each value of the signal parameter. Of the intelligence signal, the value of the signal parameter to be taken into account in the determination of the control signal is measured prior to the traversal of the signal path, and the control signal assigned to this value is selected.The control signal can be used in DME transponders to set an exact transponder delay, and in DME interrogators to allow for delay variations in the distance measurement.

Abstract: Prism couplers are manufactured by disposing a prism (10) on an optically flat waveguide (11) such that the region therebetween is shaped for substantially optimum coupling of optical energy therebetween, and securing the prism to the waveguide without deformation of the waveguide. The prism may have a curved, for example part-cylindrical, base (FIG. 4) or be separated from the waveguide by appropriate spacers (FIGS. 5 or 6). The prism may be secured to the wavegudie by an optical epoxy compound.

Abstract: The locating function of a cellular mobile radio telephone system is implemented so that, when the locating radio detects a sustained change from a very low signal quality or amplitude (indicating background noise rather than an active call in an adjacent cell) to a higher quality or amplitude (indicating the start of a call in one of the adjacent cells), the radio will modify its filtering process so that previous sample values (which can be attributed, for example, to noise before the start of the call) will not be used in the averaging process. The result of this improvement is that values reported from the locating radio during the initial portion of the call (0 to 20 seconds) will not be reported artifically low. This allows the system to make decisions about handoff during this initial portion of the call. Additionally, rather than having the locating radio take equal samples from each of the possible voice channels, in accordance with the invention, there are two scanning tasks.

Abstract: A fiber optic cable includes layers and elements for mechanical and fire protection of the cable, all having the same or substantially the same thermal coefficient of expansion as the optical fibers. The fiber optic cable core is protected against flames by at least two layers of mica separated by a layer of synthetic material.