Abstract: The disclosure is of facsimile apparatus having support means for holding a telephone handset during operation of the machine in receiving or transmitting a message. This means comprises a seat of rubber on which the handset rests, and, in addition, a ring of smooth material on which the handset slides as it is brought into engagement with the support means and as it is slipped into its operating position with respect to the support means. The apparatus also includes a novel, spring support arrangement for the handset support.

Abstract: Apparatus for enhancing the resolution of a sound detector of the type which includes an acoustic mirror for focusing sound from an object onto a microphone to enable the determination of the location from which the sound arises. The enhancement apparatus includes an enclosure surrounding the space between the mirror and microphone, and containing a gas heavier than air, such as Freon, through which sound moves slower and therefore with a shorter wavelength than in air, so that a mirror of given size has greater resolving power. An acoustically transparent front wall of the enclosure which lies forward of the mirror, can include a pair of thin sheets with slightly pressured air between them, to form an end of the region of heavy gas into a concave shape.

Abstract: An idle channel test is provided for a digital time division multiplex and time switching network telecommunications system to detect and diagnose faults in an information path which routes digital information in dedicated channel time slots to and from a "time" switching network. In order to detect and diagnose faults in the information path which includes multiplex/demultiplex circuitry, an idle channel is selected as a test channel at the input to the multiplexer which in turn is the input to the switching network, a test pattern including a bit pattern and a parity bit is inserted into the test channel, the test pattern is connected via the switching network back to one of the demultiplexers and the bit pattern and parity bit are monitored for errors.

Abstract: An identifier circuit for connection between a telephone system party line and a party line subscriber to permit identification of a calling party line subscriber with automatic number identifying equipment at a central office.

Abstract: A digital data modem arrangement is disclosed for use in a multi-drop communication system using either telephone lines or a pair of conductors. The communications device connected to a communications channel is readily adapted to a voice grade telephone line or a pair of continuous conductors. The disclosed digital data modem is capable of operating with either type of communications channel without the need of bridging amplifiers, and without substantially loading the impedance of the communications channel.

Abstract: A frequency band compression method, using Time Compression, for use with a frequency division multiplex (FDM) signal carrying voice signal. On the transmission end, the multiplexed signal is divided into a plurality of time segments, each segment having a certain duration, then deleting a part of the each segment and time-expanding the remaining part of the segment by a sawtooth variable delay, thus lowering the frequency of the signal to a predetermined ratio. On the receive end, the signal segments are compressed by a corresponding variable delay, thus making the received frequency higher and reproducing the original multiplexed voice signals.

Abstract: Apparatus and methods relating to "quadrasonic" encoding and decoding systems, including synthetic supplementary channel systems, matrix logic systems, and systems employing stereo compatible matrix variations.

Abstract: A magnetic pulser having an energizing winding and a set of normally closed contacts is connected in the ignition system of an internal combustion engine with the contacts in series with the primary winding of the ignition system coil and the energizing winding of the pulser connected in parallel with the primary of the coil. The pulser includes a spring which biases the contacts toward a normally closed position and the strength of the spring is selected so that it is sufficient to resist opening of the contact set until the breaker points of the distributor are opened by the distributor cam.

Abstract: In this speakerphone the peak value of the microphone output must be above the (variable threshold) average value to cause switching to transmit mode, thus providing dynamic compensation for ambient noise. In addition, a feedback path rapidly reduces the average value threshold if ambient noise such as a fan suddenly stops to cause the average value to be momentarily larger than the peak.

Abstract: A telephone network protective coupler for connecting terminal equipment to a telephone central office by means of a telephone line. The coupler includes two hybrid circuits which are interconnected to form a transmitting path and a receiving path. A power limiter in the transmitting path can be programmed remotely by selection of an external programming resistor without the direct introduction of noise into the transmitting path. The programming feature permits the gain of the transmitting portion of the device to be varied in steps from 0 to -12dB., and the maximum power output to be varied correspondingly in steps from 0 to -12 dBm. in order to arrive at an optimum signal power level of -12dBm. at the central office. The power limiter includes a controller gain amplifier for varying the attenuation of the transmitting path to a.c. signals, a remotely adjustable attenuator connected to a d.c.

Abstract: Like a conventional time division multiplex communication device, a device according to this invention comprises first terminals, a switching matrix, transducers or C/E buffers, control circuits, and second terminals. The first and second terminals are for low-speed and high-speed signal sequences. The control circuits are connected to the second terminals. In contrast to the conventional one, the transducers are connected to the respective first terminals, with the switching matrix interposed between the transducers and the control circuits and rendered capable of dealing with the high-speed signal sequences, among others, rather than the low-speed ones as in the conventional device. The devices are particularly useful in earth stations of TDMA satellite communication to which multi-transponder operation is applied, although useful also in carrying out conversion between low-frequency analog signal or PAM signal sequences and PAM signal sequences of a higher rate.

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: A solid state pulsing circuit and an adapter connector for pulsing the counting and register advance terminals of the L-(line) relay of an originating register in accordance with the digit nature of received DTMF signals is disclosed. The pulsing circuit includes a pair of solid state switches adapted to be alternatively actuated and the adapter connector connects the pulsing circuit to the counting and register advance terminals of the line relay without affecting the normal operation of the relay. Complementary MAKE and BREAK signals derived from the serial pulse output of a DTMF receiver operate the solid state pulsing circuit such that the pulsing circuit alternately pulses (opens and grounds) the counting and register advance terminals of the line relay in accordance with the production of pulses by the DTMF receiver. Other relay terminals (i.e.

Abstract: Apparatus for protecting low voltage lines of a telephone system and including a jack block which may be mounted on a circuit breaker means having separable contact blades and such jack block has protecting elements including a plug with a plurality of contact studs that may be selectively inserted between the contact blades of the circuit breaker means.

Abstract: A receiving amplifier AR and a transmitting amplifier AT at a telephone-subscriber station have operating circuits in respective diagonals A-D and B-C of a bridge circuit whose four impedance arms are formed by two fixed resistances Z.sub.1, Z.sub.2, a variable resistance Z.sub.3 and the resistance Z.sub.4 of a line linking the subscriber station with an associated central office. The variable bridge resistance Z.sub.3 includes a plurality of resistors selectively insertable under the control of a voltage sensor and stabilizer SL connected across the transmitting diagonal B-C which also biases a variable-gain input stage of each amplifier AR, AT to adapt it to the line resistance. A final stage of the transmitting amplifier AT has an input connected via a negative-feedback resistance ZA to one of its output terminals whereby the effective resistance of this amplifier is reduced to a small fraction of the two bridge resistances Z.sub.1, Z.sub.3 in parallel therewith.

Abstract: This device comprising a pulse receiving circuit, a computer interface circuit responsive to a logic adaptor circuit and delivering, as tax accumulation data are delivered to the device, a signal corresponding to the price of each unitary tax, an adder circuit connected to the output of said computer interface circuit for summing the prices of the various unitary taxes accumulated since the device had been reset for the last time, and a announcer for displaying this sum corresponding to the price to be paid for the service rendered. With this device, it is possible to easily check a debit corresponding to a service rendered, by calculating and displaying the sum to be paid.

Abstract: An automatic telephone dialer is described which includes a dial tone detection circuit. The dial tone detection circuit responds to a series of tones which are prerecorded on a magnetic tape. The dial tone detection circuit operates to detect the tones and to provide a signal suitable to activate a dialing relay for tone bursts on the tape of a suitable predetermined duration. Upon receipt of a suitable duration tone burst, the tone detection circuit provides an accurate duration signal to provide a relatively identical delay at the beginning and end of a dialing pulse to thereby maintain an accurate dial mark/space ratio determined by the requirements of the telephone line which is accessed by the dialer.

Abstract: There is disclosed a protective coupler for use with key telephone line units (KTU) to provide isolation between the terminal equipment and the central office line. The protective coupler plugs onto the KTU option socket and establishes a dielectric barrier to protect the system from possible overvoltages, guarantees a balanced termination, and meets leakage requirements while remaining operable to pass control and voice signals between the network and station equipment. The central office side of the barrier contains a current sink for control purposes as well as a gain compensation circuit to adjust for varying distances from the central office.

Abstract: A rotary telephone dial, in which at least one shaft is fixedly planted on a base plate. A rotary member is rotatably mounted on the shaft. Another base plate is engaged with the free end of the shaft to support the shaft. One direction assembling can be performed as a result of the above structure. A finger moving compensation mechanism is provided to obtain a sufficent allowable range of finger moving. The spring retaining structure and the governor mechanism are improved to effectively reduce the number of parts and to realize simplification of the manufacturing process.

Abstract: The telephone system includes N line paging lockout printed circuit cards, where N is equal to an integer greater than one. Each of the paging lockout cards includes a first relay controlled circuit to lockout (N-1) of the paging lockout cards from a paging amplifier if any of the (N-1) of the paging lockout cards attempts to initiate a paging operation a fraction of a second after one of the N paging lockout cards has initiated a paging operation. A second relay controlled circuit applies a busy tone to a telephone subset associated with each of the (N-1) of the paging lockout cards attempting to initiate a paging operation after the one of the N paging lockout cards has initiated a paging operation.