Abstract: The transmitter-receiver module includes a four-terminal coupler (2). An oscillator (1) and two diodes (4, 4') are connected to three of the terminals, while the fourth is connectable to an antenna (3). The diodes are used as a modulator during transmit, and as a mixer during receive. When transmitting, the oscillator is used as a signal source, and when receiving, it is used as a local oscillator. The module is implemented using fin-line technology. Several ways of realizing the oscillator are given.

Abstract: An apparatus for frequency-modulating telecommunication carriers with baseband signals includes an arrangement for generating two quadrature-related baseband signals in two separate channels, wherein each of the quadrature-related baseband signals is a sinusoidal function of the instantaneous angle of the message signal to be transmitted. The apparatus further includes an arrangement for producing a frequency-modulated carrier from the quadrature-related baseband signals, this arrangement including a device that provides two quadrature-related carrier-frequency waveforms, two mixing devices each for individually mixing one of the quadrature-related carrier-frequency waveforms with one of the quadrature-related baseband signals in one of the channels, and a combining device which combines the output signals from the two channels into a single frequency-modulated carrier-frequency output signal.

Abstract: There is disclosed a communications system in which digital information is conveyed over a line and each station on the line has a hybrid circuit. The invention includes an apparatus having means for cancelling an unwanted echo signal between receive and transmit channels at each station. An analog to digital converter in the receive channel has a control input to receive a timing signal. A subtractor circuit has a first input coupled to the output of the digital to analog converter through a filter and receives signals from a canceller sample and hold circuit having an input coupled to the transmission port. The adaptive echo simulator is a transversal filter which has varying coefficient capability and which coefficients are varied by means of multiplexers included in coefficient generators.

Abstract: The moving coil (voice coil) of the loudspeaker is so designed that the loudspeaker will become suitable for automatic production. For this purpose, the moving coil is positioned on a coilform, and as a connecting line extending to the ends of the moving coil there are used flexible ribbon conductors secured to a plastics carrier.

Abstract: A method of detecting the presence of flaws in wire as it passes through a wire drawing die involves monitoring the output in the megacycle range of an acoustic sensor attached to the drawing die.

Abstract: A surge protector with first and second electrodes, with a heat sensitive member and with a contact member which is electrically connected with the first electrode and which is mounted so as to be brought into contact with the second electrode upon the temperature of the heat sensitive member reaching a predetermined value when receiving heat from the protector. In an embodiment, the heat-sensitive member is composed of a material whose shape is a function of its temperature, such as a shape memory alloy. The heat sensitive member can also serve as the contact member.

Abstract: The oscillator includes a two-terminal device (1) as an active element and an impedance-matching network (4) for matching the two-terminal device to a load (A). The impedance-matching network is formed by a coupler (4) having four terminals (2, 3, 7, 8) two of which (7, 8) are terminated with impedances (5, 6) whose values are chosen depending on the output power or frequency to be adjusted or are varied as desired. Another of the terminals is connected to the active two-terminal device (1), and the fourth terminal (3) is the oscillator output.

Abstract: A multiwinding inductor is disclosed which inductor is employed in a power control circuit. The power control circuit is of the type having a transformer which has a center tapped primary winding coupled to and associated with a plurality of secondary windings. The primary winding of the transformer is switched by means of switching devices during a power control operation. The inductor has a first winding in the primary which winding has one terminal coupled to the center tap and a second terminal coupled to a generator and a filter arrangement. Another winding of the inductor designated as a free wheeling winding is in series with an auxiliary impedance and has one terminal coupled to the common terminal of the switching devices and a second terminal coupled through a rectifier to the generator. At least two additional windings of the inductor are coupled to suitable rectifier circuits associated with the secondary windings of the transformer.

Abstract: A coding and decoding arrangement situated between and connected to digital and analog telecommunication lines includes a plurality of signal processing components which are arranged in respective receive and transmit paths and which process incoming digital signals and convert them into analog signals, and convert outgoing analog signals into digital signals and process the latter. A plurality of multiplexers is provided, each arranged ahead of one of the components in the respective receive and transmit path, and having respective test paths connected thereto. The multiplexers can be switched by control signals such as to selectively form test routes through the arrangement, each test route including a different combination of the components, so that testing signals can be sent through such components via the test routes for testing the performances of such components.

Abstract: The present invention relates to a pushbutton switch assembly for use with telephone sets, having an integrated lock-down switch. With the aid of a rotatable trip cam of the lock-down switch, randomly one of several domes of a rubber-like switching mat of the pushbutton switch assembly can be actuated, so that certain operational conditions can be switched.

Abstract: An improved circuit for performing high speed arithmetic computations is described, and includes a mechanism for dynamically deleting faulty data bits in a configuration for minimizing propagation delay paths. The invention is particularly applicable to an associative processor wherein the data word length and rate of flow of data may vary from one instruction to the next. In accordance with the invention, data propagation delay time is minimized as is the number of required circuit interconnections, thereby making the invention easily manufacturable on an LSI chip. The advantages of the circuit design are multiplied in an associative processor, since such processors are highly reconfigurable and must be able to exclude unwanted bits from an arithmetic operation, to change data word sizes and to delete failed bits.

Abstract: A design of magnetic field actuated sealed electrical contact unit for an electrically operated relay or mechanically operated switch is constructed of metal and plastics laminae (1, 1a, 2, 2a, 5 and 5a) one of which incorporates a diaphragm 10 which functions both as moving contact and armature. In the case of a relay the electromagnetic energizing unit (3, 3a, 4 and 4a) may also be of laminar construction.

Abstract: An optical transmission system comprises a light source, which may be coherent or incoherent, a first optical interferometer wherein light from the source is modulated, an optical path, which may be either free space or an optical fiber, along which the modulated output of the first interferometer is propagated, a second interferometer wherein light received from the optical path is demodulated, and a photodetector to which the demodulated output is applied. Typically the first interferometers is a Fabry-Perot etalon, the length of the resonant cavity of which can be altered to modulate light applied thereto.

Abstract: A clock extraction circuit for PCM NRZ signals which delivers substantially constant power and comprising at least one energy storage device charged by a constant current and discharged into a full wave amplifying circuit, the amplifying circuit delivering power to a filter which filters out the clock signal. This arrangement uses a passive tank circuit and ensures the clock signal from the NRZ data does not die out during periods of little or no clock content in the data stream.

Abstract: The device is associated with a logic apparatus thereto four lines are coupled for transmitting logic data having a predetermined frequency and supplying at the output thereof a multiplexed signal having a frequency which is four times the mentioned frequency and responsive to the control of the subject device which comprises a binary digit pseudo-random sequence source and four Exclusive-OR logic circuits coupling said source to said apparatus in such a way as to define for said multiplexed signal a pseudo-random sequence having a period 2.sup.7 -1, as the tributary data is T1=T2=T3=T4=".0.".

Abstract: A pump impeller to be used when pumping liquid containing solid bodies. The impeller is provided with one single vane designed with a hollow for balancing the impeller. The hollow is connected to the surroundings via a slot at a point where the vane has its maximum diameter. The impeller is then perfectly balanced when rotating in liquid as well as in air.

Abstract: When television signals are transmitted digitally over PCM networks, it is sometimes necessary to reduce the bit rate of video signals, such as chrominance signals, on the transmission path from the rate given by the sampling frequency without significantly impairing the picture quality. To accomplish this, the transmitting portion of the novel transmission system includes a transmit filter (FIG. 2) which, at every other sample value in the horizontal and vertical directions of the picture, transmits a numerical value (C) which has the same number of bits as the sample values and depends on this sample value and the sample values of surrounding picture elements, and the receiving portion includes a receive filter (FIG. 3) in which the values of the picture elements to be inserted between the transmitted picture-element values are calculated from the values received for the surrounding picture elements.

Abstract: A stored program telecommunications system of the hybrid PBX/ey system type. The system uses two level distributed processor architecture for control and switching and pulse code modulation (PCM) for speech transmission. The system controller directs operation of the second level or group controllers, there being one group controller for each group of ports. Ports may be station instruments of either the single line or multiple line type, trunk lines or data terminals. Data from the data terminals is generally slower than the repetition rate of PCM data, therefore system time slots capable of PCM transmission may be allotted to handle more than one data terminal through sub-multiplexing of time slots. The sub-multiplexing of PCM time slots is controlled by the system controller acting through the controller for the group initiating the call with a data interface circuit providing access between a data terminal and a group level speech bus. One data interface circuit may control up to four data terminals.

Abstract: A terminal station for communication with one or more similar remote stations via mains wiring includes a piezo-electric coupler (22) whereby carrier signals are transmitted to and received from the line (24). The coupler is driven by an oscillator (21) modulated in correspondence with an input signal and tuned to the resonant frequency of the coupler.

Abstract: A processor controlled PBX system with central control and distributed group control using a processor per group. The PBX employs time division controlled speech transmission and data switching. Features of the system are programmable by the system maintenance personnel. The programmable features include the number of time slots or channels in use triggering a priority call control mode. The transfer of data between processors for monitoring may also be controlled along with the correction of data in system backup memory.