Abstract: In a rotation input device, a planetary carrier, connected to an operation knob, rotatably supports a planetary gear which meshes with an outer teeth row provided for a sun gear, to which an output shaft is secured, and also meshes with an inner teeth row provided for an outer gear. A plunger provided for the sun gear is in elastic contact with a recess cam provided for the outer gear. A solenoid unit prevents rotation of the outer gear in accordance with an output of a magnetic sensor which faces a magnet provided for the output shaft.

Abstract: A pulse generator with a filter section limiting a band of an input signal, and a pulse generating section generating a plurality of pulses which are sequentially delayed one after another by a time period (?) substantially equal to a reciprocal of a center frequency of the band of the filter section, and inputting the plurality of pulses to the filter section.

Abstract: A method of using a portable communications device includes displaying a first image of a rotary dial in a display of the portable communications device in response to a first contact by a user with a click wheel. The first image of the rotary dial includes a plurality of icons arranged proximate to a periphery of the rotary dial. The plurality of icons include numbers.

Abstract: A medium access control (MAC) entity first computes an achievable rate region based on a total transmit power limit and a channel gain of each of a plurality of WTRUs. Next, the MAC entity selects an order of DPC among the WTRUs. A rate set for use in transmitting to the WTRUs is then selected, said rate set being within the computed achievable rate region. Then, based on the selected DPC order and rate set, a DPC entity performs DPC on a plurality of data streams intended for the plurality of WTRUs. If nested lattice-based DPC is utilized, rate compatibility is achieved by selecting proper nesting ratios corresponding to a desired data rate set. Otherwise, if binary-code based DPC is utilized, rate compatibility is achieved via selecting appropriate message input sizes for input to point-to-point coding units prior to performing DPC.

Abstract: Systems and methods for orthogonal frequency division multiplexing are provided. In one embodiment, a multi-carrier modem comprises: a receiver configured to receive a waveform comprising a plurality of spectrally overlapping carrier signals from at least two of a plurality of remote units, wherein the plurality of spectrally overlapping carrier signals are modulated using an inverse Fourier transform algorithm; a transmitter; a processor coupled to the transmitter, wherein the processor outputs data for transmission to the transmitter, wherein the processor applies an inverse Fourier transform algorithm to the data provided to the transmitter; and a controller programmed to analyze a training signal received from a first remote unit and adjust receiver equalizer parameters based on the training signal.

Abstract: A present invention comprises a device and method for monitoring dial pulse (DP) signals on a line and recognizing a digit pattern comprising at least one digit on the line. In response to the recognized digit pattern, the invention determines when to initiate transmission of DTMF signals corresponding to dialed DP digits and initiates the transmission of DTMF signals at the determined point in time, which may be immediately or after a predetermined number of dialed digits or after a predetermined dialed number.

Abstract: A redial system for a VoIP modem includes a subscriber line interface circuit (SLIC) for interfacing analog telephone signals from a telephone set to the VoIP modem and for generating redial signals to a public switched telephone network (PSTN), a first relay for connecting the telephone set with the PSTN or connecting the telephone set with the SLIC, a dummy load, a second relay connected between the PSTN and the dummy load for establishing or de-establishing a connection between the PSTN and the dummy load, a third relay connected between the first relay and the SLIC for establishing or de-establishing a connection between the first relay and the SLIC, and a control circuit for controlling the second and third relays to establish the connection between the PSTN and the dummy load and de-establish the connection between the first relay and the SLIC during the generation of the redial signals.

Abstract: According to an embodiment, a DC driver circuit is coupled to a tip/ring line. The DC driver circuit includes a first capacitor coupled to a first switch where the first switch is coupled to an amplification circuit. An RC circuit is coupled to a second switch where the second switch is coupled to the amplification circuit. During a make state, the first and second switches are closed, causing the amplification circuit to draw current from the tip/ring line. During a break state, the first and second switches are open, preventing the amplification circuit from drawing current from the tip/ring line. The transition from the make state, during which a significant amount of current is drawn from the tip/ring line, to the break state, during which no current should be drawn from the tip/ring line, occurs at a rate that results in a significantly reduced voltage peak at the tip/ring line.

Abstract: A pulse dialing system for a VoIP modem includes a subscriber line interface circuit (SLIC) for interfacing analog telephone signals to digital signals, a relay for selectively connecting a telephone set with a public switched telephone network (PSTN) or with the SLIC, and a control means, coupled to the SLIC and to the relay, for receiving a digit of a dialed telephone number and for controlling the relay to connect the telephone set with the PSTN and with the SLIC alternatively for a number of cycle(s) equal to the digit of the dialed telephone number so as to generate pulse dialing signals to the PSTN.

Abstract: The method and system determines if modem pulse dialing has been requested in a telecommunication system having both a modem and an associated modem driver. When modem pulse dialing is requested, a fast timer is activated by the modem driver in association with a slow timer in the modem by stopping the fast timer, calculating a divisor value to set-up an interrupt period for the pulse dialing and restarting the fast timer utilizing the interrupt period. The fast timer is started and stopped by enabling/disabling timer interrupts. By synchronizing the fast timer and the slow timer to count in millisecond increments with the modem continuously operating utilizing both the slow timer and the fast timer, the timer resolution necessary for modem pulse dialing is produced. The modem releases control to the operating system during inter-digit delay time.

Abstract: A DTMF signal generator simplifies frequency characteristic design of a telephone line interface so as to make it easy to carry out alteration of a low tone group frequency component and a high tone group frequency component of a DTMF signal, and to lower cost by doing away with the need for a D/A converter. There are provided first and second sine wave generators (201 and 202) for respectively generating sine waves of specific frequencies, a combining circuit (210) for combining and outputting the outputs of the first and second sine wave generators at a specified ratio, a PWM modulator (214) for generating pulses at a width corresponding to the output of the combining circuit, and a filter (211) for removing undesired frequency components included in the output of the PWM modulator. The combining ratio of the combining circuit is variable.

Abstract: In a circuit for producing output pulses which correspond to pre-selected voltage pulses occurring in an input signal train; means connected to derive from said input signal train a succession of unidirectional pulses, at least some of which pulses occur in time coincidence with the leading and trailing edges of said pre-selected voltage pulses; means including a one-shot multi-vibrator connected to receive said unidirectional pulses and produce a first series of pulses having a uniform duration less than the duration of said pre-selected voltage pulses, means including a bi-stable multi-vibrator connected to receive and produce from said first series of pulses a second series of pulses equal to one half the number of pulses in said first series occurring in a given time interval, and means including a discriminator circuit connected to receive said first and second series of pulses and derive a third series of pulses which corresponds to said pre-selected voltage pulses occurring in said input signal train.

Abstract: A system and method for allowing callers using DP telephones to access IVR systems, including monitoring DP signals until a dialed digit is recognized, where the DP signals are generated by a transmission element and received by a reception element within a telephone network, and where the monitoring does not interfere with the DP signals, sending the dialed digit to a DTMF transmitter, and outputting a DTMF signal following the DP signals on a speech path, wherein the DTMF signal corresponds to the dialed digit.

Abstract: An adjustable-period dual-tone multifrequency (DTMF) generator, which includes a plurality of programmable counters or up/down counters, a control unit, a memory unit for storing data, a digital adder, and a digital-to-analog converter. The programmable counter and the control unit are combined together to form into at least two programmable counting address generators, in which the circuit is a digit-process circuit for overcoming the problem of signal distortion that usually exists in an analog circuit.

Abstract: The method and apparatus of the present invention permits data entry in an electronic apparatus without using a keypad. By rotating a moveable element (104), a function, letter, or number is selected. The moveable element (104) is then moved in another direction to enter the selected item. The function, letter, or number can be displayed on a display (106), announced with a synthesized voice, or displayed and announced.

Abstract: A serial data generating circuit and a key input signal generating circuit are provided at a panel substrate side, and input key data are transmitted in series to a main substrate side of a telephone apparatus. The number of signal lines connected between the panel substrate and the main substrate are reduced. Further, on the main substrate side downstream of a selection circuit, a data converting and producing circuit which converts the serial input key data into parallel dial data is provided to permit switching of the signal source between a processor and the panel substrate to thereby enable a dial call origination even during a power failure condition.

Abstract: A locator aid for identifying and permitting the actuation of the number "9" and "1" keys of a rotary or touch telephone keyboard. Each locator includes a base which is fixedly positioned with respect to the telephone, an elongated guide strip, and an intermediate hinge connection between the base and the guide strip. Each base is positioned with respect to the telephone so its guide strip will lie in spaced relation to a finger hole of a rotary dial or in overlying relation to one of the keys of a keyboard. In a preferred construction the locator is constructed of a die cut plastic strip and includes multiple, bendable hinge joints and an adhesive fastener, which permits selective attachment of the locator to a phone body. In other constructions, the locator is integrally molded as an selectively attachable member or is molded as part of the keyboard.

Abstract: A circuit for generating dial pulses and a circuit for forming the direct current loop of a line have conventionally been made up of relays and a coil. In the present invention, these circuits are made up of components, such as capacitors and a semiconductor switching element, to render a network control unit smaller. A compensating circuit is provided for reducing the distortion (caused by the capacitor in the DC loop) of the waveforms of dial pulses and rise waveforms of a direct current when the direct current loop is formed.

Abstract: A subscriber set includes two line terminals, and electronic telephone set circuit, and a hook switch for switching the line current.

Abstract: A DTMF signal generating circuit for producing output of a selection signal having a frequency corresponding to a signal entered from push buttons. A high frequency oscillation signal output from an oscillatory circuit are delivered to both a first frequency dividing circuit for dividing high frequency signals by a first dividing ratio and a second frequency dividing circuit for dividing high frequency signals by a second dividing ratio, thereby producing two kinds of divided signals each of which has its own predetermined frequency. A fractional frequency division is then accomplished by switching from an output of a first frequency dividing circuit to an output of a second frequency dividing circuit at a predetermined timing. The signals output form the switch are then counted by a ROM address counter, producing an output of an address value signal.

Abstract: A telephone circuit subset arrangement in which the base/emitter junction of a switching transistor (TR1) coupling an internal battery (B1) to the dialler chip's power terminals (VDD, VSS) is shunted by hook-switch signal contacts (HS) when the subset is brought into the off-hook mode, thereby turning the switching transistor off and disconnecting the battery. The circuit is so arranged that upon the switching transistor turning off, three auxiliary switching transistors (TR3, TR4 and TR5) turn on and operate the subset's line switch to connect line current to the dialler chip's power terminals. A network of resistors (R1, R2 and R3) associated with the switching transistor (TR1) ensure that on the one hand sufficient current is available to turn on the auxiliary switching transistors, and on the other hand limit the current to a magnitude which dose not cause excessive battery discharge while the subset is off-hook.

Abstract: A signal transmission circuit of a telephone system comprises a photo-transistor with its emitter and collector connected to telephone network lines, respectively. First and second relays are disposed, respectively, in the telephone network lines between a primary winding of a voice transformer and the collector and in a line between the base and the primary winding of the voice transformer. When a telephone call arises, the first relay connects the primary winding to the collector of the photo-transistor and disconnects a resistor, which is disposed between a junction of the primary winding and the second relay for connecting the base of the photo-transistor to the junction, from the primary winding so as to transmit voice signals through the voice transformer. When dialing is performed, the first relay is caused to disconnect the primary winding from the collector and connect the resistor to the primary winding, in a closed loop.

Abstract: A connecting line is provided between a switching center and a subscriber for transmission of telecommunication signals. At the subscriber's end of the connecting line, there is located a device which, in addition to other passive and active units, includes a transformer, whose output winding is subdivided into two partial windings of identical size. A first capacitor, a switch and a second capacitor are connected in series between the partial windings. To prevent distortions of the dial pulses, a connecting line between the switch and the second capacitor is connected with a reference potential of the circuit arrangement.

Abstract: A telephone system having a dial data changeover switch transmits either a dial pulse signal or a dual-tone multifrequency signal along a telephone line. This telephone system includes a changeover switch for changing between a KEY signal from a key board and a control signal from a CPU. When a power interruption sensing device senses that the external power voltage is below a predetermined voltage, the changeover switch shunts from the control signal to the KEY signal and transmits either the DTMF signal or the DP signal along the telephone line.

Abstract: A keypad monitor which monitors the condition of a plurality of switches of a keypad is activated in response to receiving clock signals from an external clock source and is deactivated in the absence of the clock signals. The keypad monitor includes a key switch monitor which detects the closure of any one of the keypad switches to provide a first output signal, a clock detector for detecting the absence of the clock signals to provide a second output signal and any key down output logic which is responsive to the first and second output signals for providing an activation signal. The activation signal causes the external clock source to provide the keypad monitor with the clock signals for activating the keypad monitor.

Abstract: Disclosed is a dialing apparatus used for a power failure extension telephone set 30 in a key telephone system. The power failure extension telephone set 30 is driven by power supplied from a key service unit 2 so as to function as an extension telephone set when power is supplied to the key service unit 2, but directly connected to an office telephone line 1 so as to function as an individual telephone set when power is not supplied to the key service unit 2. The dialing apparatus comprises a dial switch 31 of single contact-layer structure and a control switch circuit 21 connected to the dial switch 31 and changed over according to the power supply or power failure condition of the key service unit. That is, when power is supplied to the key service unit 2, the control switch circuit 21 connects the dial switch 31 to a control circuit 19.

Abstract: A liquid crystal display driver and power supply for use with a telephone dialing circuit reduces the potential of an external power supply to the telephone dialing circuit to a desired voltage level. The reduced potential is then stabilized and a second voltage signal, which is a function of the stabilized voltage signal, is generated to drive and supply power to a liquid crystal display of the telephone dialing circuit. The liquid crystal display driver and power supply and the telephone dialing circuit can be integrated in a single IC chip.

Abstract: A circuit arrangement of simple structure for producing dialing pulses for a telephone transmission system so as to provide a relatively low insertion attenuation during transmission. The impedance of the transmission system should not be reduced. At loop closure the a.c. impedance of the circuit is high-ohmic and for d.c. current the circuit has a very low resistance. A switching apparatus is connected to the wires of a connecting line in parallel with the transmission system. The switching apparatus is arranged as a series connection of a bipolar transistor and a switching element consisting of a MOS field-effect transistor.

Abstract: A telephone line interface circuit for connecting telephone equipment provided with internal speech lines having predetermined DC impedance to external telephone lines, comprising a rectifying circuit connected with the telephone lines for rectifying the DC voltage coming from the telephone lines; a dial pulse sending circuit which makes connection and disconnection between the output terminals of the rectifying circuit and the internal speech lines for sending dial pulses to the telephone lines; and a polarity inversion detecting circuit which discriminates th evoltage relationship between the telephone lines and the internal speech lines for detecting the polarity inversion of the DC voltage coming from the telephone lines.

Abstract: A dialer circuit equipped with built-in dialer memories for auto-redial or abbreviated-dial telephone communication and operable to send out a DTMF signal or a pulse signal to a telephone circuit based on a key input signal. A battery voltage is supplied to the dialer memories from a back-up battery, while a supply voltage is supplied to the other function circuits from a telephone circuit line. A voltage level converter means is located between the dialer memories and the other function circuits and eliminates production of through current resulting from the difference between the back-up battery voltage and the line voltage.

Abstract: A dialer circuit comprising a microcomputer for controlling the dialing of a telephone. This dialer circuit is capable of storing a telephone number and transmitting a signal concerning this telephone number to a telephone circuit according to a given command. The dialer circuit is equipped with a means for detecting the ON state or the OFF state of a hook switch; upon detection of the state of the hook switch, the dialer circuit performs a resetting of the entire system except a memory in which the telephone number is stored. The result is that when operating the hook switch, it is possible to automatically reset only the system, thus effectively preventing any reckless driving of the system.

Abstract: A dial signal generator supplied with dial data corresponding to a dial number, includes a dial data register for storing the dial data, a decoder for decoding the dial data supplied from the dial data register to thereby generate corresponding row and column numbers based on a dual tone multi-frequency (DTMF) system, a DTMF generator for generating a DTMF signal from the row and column numbers generated by the decoder, and a dial pulse generator for generating a dial pulse signal from the dial data supplied from the dial data register.

Abstract: The dialer IC according to the present invention is capable of expanding an access-pause of the push-button telephone and adapting itself to a wide variety of dialing services.

Abstract: Telephone instruments generally comprise a mechanical hookswitch connected across the pair of speech wires. This specification discloses solid state hookswitch circuitry comprising a switching transistor controlled by a hookswitch and connected in series with the output of a rectifier, the rectifier being connected directly to the incoming speech wires. Because the hookswitch controls a switching transistor, rather than having to switch line voltages directly, any reliable low current make/break switch may be employed.

Abstract: A digital telephone set dial pulsing circuit in which the line current switching element is a bipolar transistor. To keep such switching transistor constantly in the saturated state irrespective of the magnitude of the line current, its base is driven by a current source supplying a current linearly related to the line current. In order to prevent an excessive voltage drop in the current source, which would reduce the voltage for the remaining circuits of the telephone set, the current source is voltage-controlled by a control circuit which provides a control voltage linearly related to the line current.

Abstract: A key-in sound-generating circuit comprises a keyboard including dial number keys and function keys, a DTMF signal generator coupled, at the output terminal, with a telephone network, a sound generator for converting, into a sound, the output signal from the DTMF signal generator, and a data processor circuit for executing the key data processing according to the keying operation performed using the keyboard, and supplying a control signal to the DTMF signal generator, the data processor being responsive to the operation of the dial number key, to supply a DTMF signal to the keyboard and the sound generator, and responsive to the operation of the function key, to supply a single-frequency signal to the keyboard and the sound generator.

Abstract: A circuit for surge voltage protection of therefor a telephone station has first and second input terminals for receiving a DC supply voltage via a two-wire subscriber line. Both terminals are shunted via a varistor. In parallel with the varistor is an element for protecting the circuit against polarity reversals. This element has two outputs, one of them carries the positive potential of the DC supply voltage and both of them are connected with respective terminals of the actual station circuit. A V-MOS or bipolar tranistor is arranged between the one output and the associated station circuit terminal. This transistor belongs to a current limiting circuit and serves also as a dialswitch-pulsing contact. The transistor circuit contains two further transistors and a number of dimensioning resistors. The positive output of the protection element is connected to the keyboard-sided input of the transistor circuit via a series network formed by a reverse Zener-diode and a resistor.

Abstract: An output voltage of a first diode deriving out an office line voltage, and an output voltage of a second diode deriving out the voltage of a back-up battery are combined and then smoothed by a smoothing capacitor. The smoothed voltage is supplied to a control circuit. A voltage limiting circuit is connected to the input side of the first limiter for limiting the upper limit of the smoothed voltage. A switch circuit is provided which is rendered conductive at the time of talking and the at the time of sending out a dial pulse for combining the office line voltage with the combined voltage. A voltage limiting circuit is also provided which is enabled only at the time of talking and at the time of sending out a dial pulse for limiting the upper limit of the combined voltage.