Matches 1 - 50 out of 189 1 2 3 4 >


Match Document Document Title
5396028 Method and apparatus for transmission line termination  
A method and apparatus for transmission line termination is provided in which a transmission line (12 and 14) is terminated by transmission gates (20 and 22) at a transmitter (24) and a receiver...
4984250 DC termination circuit for subscriber cables  
A DC termination circuit is provided for keeping a sealing current on a subscriber line during normal operation in order to prevent an oxidation of contacts in said line. The termination circuit...
4777330 Network system diagnosis system  
A station diagnosis method in a communications network system including a closed ring transmission line and a plurality of data stations which can be connected to the ring transmission line by a...
4745624 Automatic line buildout  
A circuit for restoring and converting bipolar customer data signals into a pair of binary signals at a customer data frequency equal to or less than 250 KHz includes a PCM integrated circuit...
4694470 Data transmission circuit  
A data transmission circuit is disclosed which is arranged so that when transmitting data and control signals of a terminal equipment accommodated in a transmission line of 64 Kbps channels...
4680431 Data network interface module with circuitry for disconnecting a module that has lost supply voltage  
The invention relates to an interface module for the bidirectional transmission of data streams in a data network with separate power supplies for the individual bus stations. According to the...
4647912 Coupling discriminator and interface adaptor  
A coupling discriminator for Ethernet standard local area network interface equipment monitors the electrical characteristics of an incoming differential signal pair, discriminates between a...
4642426 Apparatus for locating faults in a carrier subscriber communication system  
Method and apparatus is disclosed for identifying faults in a subscriber carrier telephone system utilizing out-of-band pilot signals and comprising pluralities of cables and repeaters that are...
4633489 Interface unit inserted between a data transfer unit and a processor unit  
An interface unit is disclosed which can make asynchronous data communication between a transmitter unit and a receiver unit. The interface unit includes a shift register for receiving start data...
4622682 ARQ transmission system  
A facsimile communication system equipped with an ARQ function for transmitting data in the form of a block between a transmitter and a receiver through a transmission route having a relatively...
4607379 Circuit for connecting together multiple serial data lines  
Apparatus operable without need for an external power source for conveniently interconnecting data communication equipment (DCE), such as a modem, and multiple data terminal equipments (DTE), such...
4606043 Programmable automatic cable equalizer  
The circuit (10) has a gain section which includes a first AGC circuit (12). The output of the gain section goes to a signal shaping section which includes a biquadratic filter (24), a summer...
4434324 Reversal of connections of telegraphic line wires upon detection of unwanted polarity of the loop current  
The system comprises at least one teleprinter station (1) connected to an exchange (3) by means of a transmission-reception line (2) and comprising a polarity detector (31) for the line...
4403111 Apparatus for interconnecting data communication equipment and data terminal equipment  
An interface for connecting data terminal equipment (DTE) to data communication equipment (DCE) is provided which requires no modification to an existing and widely accepted DCE connector and yet...
4329542 Circuit arrangement for an electronic d.c. telegraph transmitter  
An electronic d.c. telegraph transmitter comprises a transmitting keying circuit and a current regulating circuit which operates in accordance with the principle of a continuous regulator and...
4121095 Optical receiver  
Optical receiver arranged to provide a dispersion-compensated detection of digital information transferred by a light pulse train via a fibre optic conductor, includes a registering means and a...
4055775 Transmission circuit for direct current data transmission  
A transmission circuit including cross coupled transistors is described. The circuit is symmetrical and the base of each transistor is coupled to the collector of the other and also to a supply...
4015190 Controllable negative resistance electronic switch arrangement  
An electronic switch arrangement reverses damping of an electronic switching element by means of a controllable negative resistance. Adjustment of the negative resistance is provided by comparing...
3980973 Line device for transmission lines having coaxial cables for the transmission of digital or analog signals  
A line device for transmission lines having coaxial cables for the transmission of signals, in particular digital signals or analog signals, employs an input equalizer in the form of a line...
3949168 Selectively clamped digital signal transmission system  
In a system including several devices connected by means of a common data bus the adverse effects of reflections due to two or more devices simultaneously seeking access to the bus are minimized...
3922487 Circuit arrangement for adjusting the line current in telegraphy subscriber connection circuits of an exchange installation  
A circuit arrangement is described whereby the line current in telegraph subscriber connection circuits can be adjusted. Each connection circuit contains a supplementary resistance consisting of...
3906174 Cable pair testing arrangement  
A pseudo-random, pseudo-ternary pulse train, which is representative of a PCM signal, is applied to one end of a cable pair. At the other end of the cable pair, the received pulse train is...
3894284 Current flow test apparatus  
The current flow test apparatus has a test connector with first and second test terminal connectors. A power connector has first and second power terminal connectors, a transistorized active...
3806814 PHANTOM SUBSCRIBER  
A system for enabling a plurality of first circuits to selectively control such functions as gain, slope, bandpass and switching of all transmissions passing through a signal distribution network...
3805241 CIRCUIT ARRANGEMENT FOR THE UNDISTURBED TRANSMISSION AND STORAGE OF ELECTRICAL INFORMATION SIGNALS AT A REMOTE CONTROL INSTALLATION  
A circuit arrangement for the undisturbed transmission and storage of electrical information signals at a remote control installation containing addressed transmitter and receiver means possessing...
3795865 AUTOMATED REAL TIME EQUALIZED MODEM  
An Automated Real Time Equalized Modem (ARTEM) having multipath equalization by means of adaptive, quadrature matched filters and an adaptive transversal equalizer. ARTEM is a wideband (3kHz)...
3790699 SIMPLEX RADIOTELEGRAPH SYSTEM  
A simplex radio telegraph system with automatic error correction, wherein message signals transmitted to a receiving station are included in time spaced frames. The time space between consecutive...
3775685 APPARATUS FOR AUTOMATICALLY CHECKING PULSE-DISTORTION CORRECTION IN A SIGNAL CHANNEL  
A distortion correction scheme and apparatus in which communication signals are transmitted in the form of discrete pulses separated from one another by individual constant amplitude pulses of...
3746993 CARRIER DETECTION CIRCUIT  
Carrier detection circuit for use with an FSK modem receiver wherein a pair of phase lock circuits connected to the receiver are tuned to provide output voltage upon receipt of either a mark or...
3715666 FAST START-UP SYSTEM FOR TRANSVERSAL EQUALIZERS  
Initial convergence of automatic transversal equalizer tap gain settings is rapidly achieved without first establishing synchronization between a test signal incoming at a receiving location over...
3697874 MULTILEVEL CODE CONVERSION SYSTEM  
A PCM code conversion and transmission system in which a code signal representative of an information signal is transmitted in the form of a train of multilevel pulses spaced by a clock pulse...
3681579 NON-INTERACTING COMPLEMENTARY CODING SYSTEM  
A system utilizing first and second pairs of code generating devices and respectively corresponding first and second pairs of decoding devices, selectively positioned in first and second...
3671671 PULSE TRANSMITTING AND RECEIVING SYSTEMS  
A pulse transmitting and receiving system comprises a transmission circuit including a balanced pair transmission line, impedances having the same characteristic impedance as the transmission...
3657669 FREQUENCY DOMAIN ADAPTIVE EQUALIZER  
A frequency domain adaptive equalizer employs a first filter, having a plurality of periodically spaced zeros in its transfer characteristics, coupled to a second filter that includes a plurality...
3648171 ADAPTIVE EQUALIZER FOR DIGITAL DATA SYSTEMS  
The automatic time-domain equalizer is modified to improve its signal-to-noise and impulse-response dispersal performance by supplementing the basic prior art equalizer with a final equalizer...
3629507 SOLID-STATE LINE KEYER  
A solid-state line keyer used in a telegraph system isolates an input signal from a signal line. The keyer includes an oscillator responsive to the input signal to which is inductively coupled by...
3617619 METHOD AND APPARATUS FOR THE TRANSMISSION OF BINARY CODED DATA WITH LOW LEVEL DIRECT CURRENT VOLTAGES  
A method and apparatus to transmit control signals such as remote connection and disconnection signals, dialing signals, free signals, etc., the amplitudes of which rather than the time duration...
3617635 TIMING RECOVERY SYSTEM IN WHICH AN EQUALIZER'S SAMPLING TIME IS SET IN RESPONSE TO THE DIFFERENCE BETWEEN THE ACTUAL MEAN SQUARE ERROR AND A PREDETERMINED ACCEPTABLE ERROR  
A system is disclosed in which an error signal used for adjusting tap weights in a time domain equalizer is integrated in an up-down counter over one-half of an interval. At the end of the first...
3611141 DATA TRANSMISSION TERMINAL  
In the transmitter, a code translator translates four digit binary code groups into three digit ternary code groups having either zero or positive disparity only and a lower digit rate thin the...
3609662 SERIAL PULSE DIGITAL TRANSMISSION SYSTEM  
A serial digital transmission system is described wherein the sending station is connected to a receiving station by way of a pair of conductors. Digital data in parallel form is applied as an...
3599148 QUANTIZING CIRCUIT CORRECTION FOR CHARACTER RECOGNITION SYSTEMS  
This disclosure relates to a character recognition system having a quantizing circuit which employs a tunnel diode as a discrimination element. This element is adapted to be triggered to produce...
3591719 AUTOMATIC PROGRAM TEST CIRCUIT FOR DATA SETS  
An automatic test circuit for simultaneously testing a plurality of data sets wherein the test circuit provided for each data set a multiphase program which includes sending test signals to the...
3588350 WIDE-BAND DC COUPLED CABLE TRANSMISSION CIRCUIT INDEPENDENT OF GROUND CIRCUIT VOLTAGE VARIATIONS  
3581075 ARRANGEMENT FOR DISCONNECTING A DEFECTIVE LOCAL CONCENTRATOR IN A DATA TRANSMISSION SYSTEM  
In a data transmission system comprising a number of remote terminals connected in series to a main terminal via a data transferring line inquiries are cyclically sent out from the main terminal...
3573370 CIRCUIT ARRANGEMENT FOR THE TRANSMISSION OF TELEGRAPHY AND DATA SIGNALS  
A circuit arrangement for the transmission of telegraphy and data signals at any speed over a line in a direct current transmission system wherein the internal resistances of the transmitters and...
3535448 TWO-CHANNEL TIME-MULTIPLEX TRANSMISSION SYSTEMS  
3522383 BLOCK PRECODING FOR MULTIPLE SPEED DATA TRANSMISSION  
3518549 AUTOMATIC PROTECTION SWITCHING SYSTEM FOR COMMUNICATION CHANNELS  
3517125 AUTOMATIC COMMUNICATION CIRCUIT EVALUATION AND SENSORY SYSTEM  
3509291 METHOD AND APPARATUS TO ADJUST THE CAPACITANCE OF A NETWORK TO SOME PREDETERMINED VALUE  

Matches 1 - 50 out of 189 1 2 3 4 >