Abstract: An interface unit, intervening in the high-speed transfer of data between an associated peripheral unit and a central memory of a processor, comprises a first and a second binary counter CM.sub.1, CM.sub.2 for the respective storage of memory addresses and of the number of data words to be read out from or written into a series of such addresses. In response to the arrival of an input/output instruction from a program memory of the processor, intended for the associated peripheral unit, a first sequential network RS' controls the loading of these counters with a starting address and an initial word count; if no other peripheral unit takes precedence, a second sequential network RS" then causes transmission of the contents of the first counter CM.sub.1, during successive cycles of a microroutine established by a control unit of the processor, to that processor followed by the readout (or write-in) of data words at the corresponding addresses, with incrementation of the address in counter CM.sub.

Abstract: A self-exciting oscillator comprises a klystron with an input cavity and an output cavity, interconnected by a feedback port, which resonate at fractionally different frequencies in the microwave range. The output cavity, alone, is tunable to vary the operating frequency within a range of about .+-.2%.

Abstract: A rotary line selector of a telephone exchange has a wiper, connected to a test wire, coacting with a multiplicity of bank contacts divided into ten decadic groups that are separated by rest positions in which the wiper may come to a halt after selection of a decadic group by the penultimate digit of a call number, the selector being then driven in response to the final digit to choose one of the ten outgoing lines whose test wires are tied to respective bank contacts of that group. If the called subscriber can be reached through a line multiple, selection of the first line--if the latter happens to be busy--brings on an ancillary relay X which connects a previously charged capacitor C in a sensing circuit including a common lead tied to the test wires of all the other lines of the multiple, operation of another ancillary relay V' then actuating a driving relay V for resumption of selector rotation while switching a test relay P from the wiper to the sensing circuit. When another line of the multiple.

Abstract: A transmitting station for wide-band signals at one end of a line such as a bifilar or quadrifilar cable includes a generator of test frequencies lying between several sub-bands--such as carrier-frequency telephone channels--normally used for message transmission. A pilot wave outside the range of message frequencies, generated at the transmission station, is modulated under the control of a transmitting-side programmer to indicate the start of a test sequence during which the several test frequencies are sequentially emitted, except when a message to be transmitted (e.g. a TV program) spans several sub-bands and requires suppression of the intervening test frequencies. At the other end of the line, a receiving station includes an equalizer with a number of individually adjustable stages pertaining to respective frequency bands centered on the several test frequencies.

Abstract: A conductive body with a cylindrical cavity, designed to resonate at a certain operating frequency in the TE.sub.01 mode, has an input opening at one end and a conductive insert at the opposite end which alters the effective axial length for parasitic waves propagated in the TM.sub.11 mode. The insert may have the form of a smaller cylinder with a closed end beyond that of the main cavity, increasing the effective length, or of a set of radial vanes reducing the effective length. The insert, in either case, may be axially shiftable to tune the cavity to different resonant frequencies.

Abstract: A conductive coil, designed to be used as an inductance in a resonant cavity, comprises a metal strip integrally cut or etched from a sheet with a branch diverging from the main stem of the strip in the vicinity of one extremity thereof bent at an obtuse angle, that extremity ending in an enlarged terminal tab serving as a ground connection. After formation of the strip, the terminal tab is bent at right angles to the extremity whereas a major strip portion is helically wound about an axis in line with the center of the terminal tab.

Abstract: A filter for a telecommunication system, designed to suppress a signal frequency F.sub.a and to transmit an adjoining frequency F.sub.b without significant attenuation, comprises a resonant cavity of prismatic shape longitudinally traversed by a conductive coil wound on a hollow dielectric core into which an adjusting screw is inserted. One end of the coil is grounded at the cavity wall while its other end is left unconnected and forms with the adjusting screw a variable capacitance C.sub.d with distributed constants; a lumped-constant tuning capacitor C.sub.1 is connected between ground and an input lead connected to an intermediate tap on the coil, the inductance L.sub.2 " of that lead and the inductance L.sub.2 ' of the coil portion between the tap and ground forming an inductive voltage divider bridged by the lumped-constant capacitor C.sub.1. The remainder of the coil, lying between the tap and the unconnected end, forms an inductance L.sub.1 which together with the distributed-constant capacitance C.

Abstract: Macroinstructions stored in a program memory MP of a data processor, read out succesively under the control of a program counter PC, are decoded in a control unit CN which establishes a macroroutine for the transfer and processing of data within the processor as well as between the latter and associated peripheral units. The control unit comprises a microinstruction memory MM addressed by a microinstruction counter CC which is supplied with a starting address from an address store MI at the beginning of any microroutine as determined by a decoding of the final microinstruction of the immediately preceding microroutine. The address store contains 16 groups of 8 cells each; a logic network RL.sub.1, responsive to various bit combinations from a primary decoder DC.sub.1 and a secondary decoder DC.sub.2 in an output circuit of microinstruction memory MM, selects one of the cells of a group activated by a multiplexer MT.sub.

Abstract: A receiver for call signals, designed to actuate an electro-acoustic transducer such as a ringer in response to incoming alternating voltages of low amplitude and relatively high frequency (e.g. 400 to 450 Hz) or high amplitude and relatively low frequency (e.g. 20 t0 50 Hz), includes a detector for the high-frequency signal and an integrating threshold circuit for the low-frequency signal connected in parallel across a transmission line. The detector is preceded by a phase-locking circuit including a local oscillator of variable frequency adapted to latch on to the high-frequency signal. The presence of either type of call signal activates, through the detector or the threshold circuit, a binary pulse counter stepped by the squared output of the local oscillator to generate a low-frequency square wave subharmonically related to the oscillator frequency which periodically unblocks a gate circuit for the passage of the oscillator output to operate the transducer.

Abstract: A circuit arrangement for feeding a sinusoidal signal current to a wide range of loads, such as ringing current transmitted over subscriber lines from a telephone exchange, comprises a modulator which converts a rectified sine wave into a sequence of unipolar constant-amplitude pulses of varying width controlling, through a logic network, the energization of a load impedance via a resonant circuit from a d-c source. A switchover unit, including a transistor bridge having a diagonal connected across the d-c source, receives command signals from the logic network in response to the control pulses and to the outputs of two sensors determining the instant polarities of the load voltage and the load current in the output of the resonant circuit. The switchover unit produces a train of bipolar driving pulses, of constant amplitude and synchronized with the control pulses, whose polarity changes with alternate half-cycles of the sine wave fed in rectified form to the modulator.

Abstract: In order to improve the utilization of a memory in an electronic processor of a telephone exchange, serving for the temporary storage of one or more 4-bit groups (referred to as quartets) in zones of 16-bit capacity, a concentration unit in the input of a logic network and an expansion unit in the output thereof are controllable to switch incoming quartets from any group position to the position of the lowest-ranking group, or pair of groups, and to switch outgoing quartets from the lowest-ranking position, or pair of positions, to other group positions. The logic network is an arithmetic unit receiving the quartets from a data memory, or from a set of working registers serving for the storage of intermediate calculation results; the outgoing quartets are fed to the data memory, to the working registers, or to a buffer register connected to a control input of the arithmetic unit.

Abstract: Binary message signals arriving over a PCM link at a retransmitting station, with a predetermined average bit cadence subject to random variations, are cyclically written in an 8-stage buffer register under the control of an 8-pulse writing counter stepped by clock pulses extracted from the incoming bit stream. The contents of the buffer register are read out under the control of an 8-pulse reading counter stepped by a local pulse generator whose pulse rate substantially corresponds to the predetermined cadence. Any deviations of the actual bit rate from the predetermined cadence are detected in a phase comparator receiving mutually interleaved monitoring pulses, once per 8-bit cycle, from the two counters.

Abstract: An electronic circuit breaker feeding a d-c/d-c converter from a power supply common to several such converters includes a normally saturated main or switching transistor T.sub.1 in series with the associated converter, the latter having an output from which auxiliary voltage is fed back to an ancillary transistor T.sub.2 lying in series with a voltage divider R.sub.1, R.sub.2 serving to bias the main transistor into conduction. A further transistor T.sub.3 triggers the cutoff of the main transistor T.sub.1 when the converter draws excess current, part of which flows through the voltage divider R.sub.1, R.sub.2. Another voltage divider R.sub.4 R.sub.5 in parallel with the first-mentioned divider biases the further transistor T.sub.3 and is thus traversed by a portion of the feedback current passing through the ancillary transistor T.sub.2, being therefore likewise cut off upon de-energization of the converter by the cessation of conduction through the main transistor.

Abstract: A terminal of a radio link or other two-way channel incapable of transmitting d-c signals, extending to a remote exchange, serves a multiplicity of local subscribers having keyboard-equipped telephone sets generating multifrequency selection signals accompanied by a d-c key signal. A detector at the terminal, responding to the arrival of a key signal from a calling subscriber line, connects that line to the outgoing channel to facilitate the transmission of the selection signals to the exchange; upon the arrival of an answer criterion from the exchange, the receiving branch of the channel is extended by another detector to the calling subscriber line.

Abstract: A main transmission line with inner and outer metallic layers on a dielectric tube is joined to a coaxial branch line via a pin and a sleeve forming extensions of the inner and outer conductors of that branch line, the pin penetrating two diametrically opposite bores of the dielectric tube while the sleeve is in contact with the outer metallic layer. Two lugs on the sleeve are soldered to that outer layer whereas a connection between the inner layer and the pin is established via a conductive coating of the wall of the remote bore which terminates in a metallic patch surrounding the outer end of that bore, the patch being insulated from the outer layer of the tube and being soldered to the projecting tip of the pin.

Abstract: A terminal serving a group of subscriber lines, some of which are invariably paired with remote stations through so-called "hot-line" connections, has a line concentrator/distributor from which a lesser number of line links extend to an automatic exchange at a nodal point of a data and/or voice telecommunication system. The line concentrator/distributor is controlled by a marker connected via a separate signaling channel with a line-control unit at the nodal point, that unit including a classifier which stores information fully identifying each associated subscriber line in terms of call number and class of service while also correlating the address of each line link on the terminal side with that on the address side.

Abstract: A multiple circuit interrupter, designed to facilitate the selective insertion of testers and other ancillary equipment into lines of a telecommunication system, comprises a body of generally rectangular outline which is receivable in a distribution frame and is split longitudinally into a central section and two lateral sections forming two rows of jacks between them. The jacks are arrayed in a plurality of groups accommodated in respective bosses of the split body projecting from a common base, each boss being engageable by a complementary socket containing a corresponding group of plugs. The bosses and the sockets are asymmetrically profiled to insure proper alignment of the jacks and the plugs.

Abstract: A network discriminating among switching signals appearing on a pair of talking wires of a telephone line comprises a light-emitting diode in series with each wire and a phototransistor illuminable thereby. The phototransistors energize respective amplifiers which work into a logic circuit distinguishing between current flow in one or both of these wires.

Abstract: To facilitate the insertion of printed-circuit boards into a holder whose sidewalls form guide tracks for these boards and whose bottom has contacts engageable by terminal tabs on the boards, as well as the extraction of such boards from the holder, a C-frame adapted to span the holder surrounds a slider having a pair of lugs which point to the interior of the holder when the frame legs come to rest on its sidewalls and which carry hooks fitting into holes of a printed-circuit board lying in the plane of the frame. The slider is biased by leaf springs into an extended position, defined by stops on the frame legs, in which it can be locked by a latch during an insertion operation. For extracting an inserted printed-circuit board from the holder, the slider is unlocked and is then squeezed against the ridge of the frame resting against the holder walls to disengage the terminal tabs from their contacts before fully withdrawing the board.

Abstract: A guide frame for the retention of printed-circuit carriers or other slidable articles comprises top and bottom members integrally molded from plastic material, each member including an elongate base with upstanding sidewalls and two sets of cantilevered ribs, the ribs of each set extending inwardly from a respective sidewall at an angle of substantially less than 90.degree. and terminating in a common longitudinally extending bar overhanging the base. The two bars are separated by a distance less than the thickness of a workpiece to be inserted therebetween, the herringbone pattern of the ribs facilitating such insertion from one end but impeding a withdrawal toward that end.