Patents Examined by Randall P. Myers
  • Patent number: 4403116
    Abstract: The body for a telephone unit is designed to permit easy removal for maintenance and for initial assembly. The escutcheon plate which is a close fit to the dial is fitted in an oval hole which allows it to move on the body to clear the dial on removal of the telephone body.
    Type: Grant
    Filed: July 7, 1980
    Date of Patent: September 6, 1983
    Assignee: Overseas Limited
    Inventors: Eric Prince, Walter P. Greenslade, David J. Hickling
  • Patent number: 4400583
    Abstract: A complete audio processing system of solid state design for providing improvement of audible signals through dynamic compression including an active filter for transient suppression, a gain control, and a plurality of active frequency control stages for selectively controlling internal gain of signals in different frequency bands. Outputs of the frequency control stages are mixed and provided to a compressor stage having an operational amplifier of gain fixed by a DC feedback network. A gain cell provides variable negative feedback. A rectifier circuit measures the average value of the audio input to the compressor stage and controls the gain cell as a function of the average value to provide negative feedback which increases as a function of increase in the level of said input signal. An attenuator receives the output of the operational amplifier and provides an attenuated but dynamically compressed output so that the circuit provides no substantial overall gain but achieves high compression.
    Type: Grant
    Filed: July 10, 1981
    Date of Patent: August 23, 1983
    Assignee: Metme Communications
    Inventor: Graham P. Bloy
  • Patent number: 4399326
    Abstract: An audio signal processing system for producing a moving comb filter effect having an all pass phase filter or other suitable phase shifting device in a first input branch and a bypass circuit with an optional inverter in a second input branch. A frequency shifter is inserted either into the first or the second input branch. A first summing network is connected to the outputs of the first and second input branch. An optional second summing network is connected to the output of the first input branch and the inverted output of the second input branch. A feedback circuit may be connected between the output of one of the summing networks to the input of the system to enhance the moving comb filter effect. Also, at least one switching circuit may be used to obtain phase reversals in the frequency shifter thereby facilitating up or down detuning or successive up and down detunings of the comb filter frequencies.
    Type: Grant
    Filed: January 12, 1981
    Date of Patent: August 16, 1983
    Inventor: Harald E. W. Bode
  • Patent number: 4396806
    Abstract: A general purpose hearing aid amplifier is programmably adaptable to the prescription requirements of the hearing impaired. The hearing aid amplifier comprises a bank of bandpass-restricted channels, each channel having a voltage-controlled input amplifier, a voltage-controlled compressor, and a voltage-controlled output amplifier for shaping the gain, attack and delay characteristics of the selected channel. The bank is fed through a fixed high-pass filter from a microphone input, and a mixed output drives a power amplifier for an output transducer such as a hearing aid speaker. The amplifier is programmably adaptable through the use of a monolithic programmable switch array using, for example, semiconductor fuseable link technology to preset digital-to-analog converters voltage controllable levels of the amplifiers and compressors of each channel according to a digital control input.
    Type: Grant
    Filed: October 20, 1980
    Date of Patent: August 2, 1983
    Inventor: Jared A. Anderson
  • Patent number: 4395599
    Abstract: Circuitry for converting a transfer function characteristic into a specified driving point impedance using feedforward techniques comprises: a directional coupler (90) having input, transmission and reflection ports; and unidirectional signal transfer means including transfer network (91) and amplifier (92) connected in cascade between the transmission and reflection ports. The impedance level of the transfer network is adjustable and is compensated for by the amplifier. A high impedance level allows for small element values for certain components such as capacitors so that a wide frequency band driving point impedance may be realized with integrated circuits. Further decrease in capacitor values is achieved utilizing capacitor magnification. The driving point impedance may be realized in balanced or unbalanced-to-ground fashion.
    Type: Grant
    Filed: November 28, 1980
    Date of Patent: July 26, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Harold Seidel
  • Patent number: 4395591
    Abstract: A telephone handset support which will allow a telephone substation to be used as either a desk or wall unit, wherein, the telephone base includes a T-shaped cavity on a face thereof, arranged to accept therein a similarly shaped retainer. The retainer is alternatively positionable to be substantially housed within the cavity, allowing the telephone instrument to be horizontally mounted, or to have an included hook extend outward of the cavity. The hook engages an orifice on the handset supporting the handset to the base when vertically mounted.
    Type: Grant
    Filed: October 5, 1981
    Date of Patent: July 26, 1983
    Assignee: GTE Automatic Electric Labs Inc.
    Inventor: John E. Kaczkos
  • Patent number: 4394545
    Abstract: To reduce manufacturing costs of telephone instruments it is desirable to secure components to housing members and secure housing members to one another without the use of fasteners. In the past this has been accomplished by the use of flexible latch elements that are deflected from their normal position in the process of assembly, and then return to their normal position to perform their latch function when assembly is complete. The problem with this arrangement is that impact, such as occurs during shipping or when a telephone instrument is accidentally dropped, has been found to cause the flexible latch elements to deflect and release the housing members and/or components they are intended to secure.The disclosed telephone instrument solves the problem of securing the components in place by having integral flexible latch elements (115) extend alongside of a wall (140) of one housing member (100) and integral blocking elements (245) included in the mating housing member (200).
    Type: Grant
    Filed: March 11, 1980
    Date of Patent: July 19, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Francis S. Doyle, Terry B. Prince, Martin J. Stevenson
  • Patent number: 4388490
    Abstract: A method for changing each of and/or arranging the sequential order of audio effects circuit modules constructed to be received in any electronic system so predisposed, noiselessly, without the generation of spurious noise signals into the main signal path of the system, during performance and all stages of operation, maintaining, all the while, the uninterrupted flow of the main signal path through the system. The effects box described herein includes a main housing containing a main circuit apparatus, and having module-receiving recesses. Modules each have multiple module contact elements positioned to contact corresponding recess contact elements when the module is installed.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: June 14, 1983
    Inventor: Abner Spector
  • Patent number: 4388500
    Abstract: An improved electronic hybrid for coupling signals between two wire and four wire transmission circuits. The hybrid includes a pair of amplifiers associated with a pair of terminating impedances which are serially connected between the amplifier outputs and the two wire port. The amplifiers driving the two wire port through the terminating impedances are biased to couple a dc potential to the two wire line whereby the terminating impedances serve as battery feed resistors. Each amplifier-impedance arrangement includes a feedback circuit connected from the junction between the impedance and the two wire port and an input of the amplifier for providing positive feedback for the amplifier so that the output impedance of the hybrid is maintained at a desired level using battery feed resistors of smaller value than heretofore required. The result is the ability to drive longer loops through the smaller series impedances while at the same time exhibiting the desired terminating impedance.
    Type: Grant
    Filed: February 27, 1981
    Date of Patent: June 14, 1983
    Assignee: Wescom, Inc.
    Inventor: John F. Regan
  • Patent number: 4387277
    Abstract: The connecting device according to the present invention comprises for a two wire to four wire converter which connects the reception channel of a private network to the public network via an amplifier, whose symmetrical outputs are connected to the public network by capacitors, the gain loss due to these capacitors being compensated by a second amplifier. For the transmission channel a third amplifier has inputs connected to the public network by capacitors and an output connected to one input of a fourth amplifier, whose other input is connected by a phase shifting network to the reception channel.
    Type: Grant
    Filed: March 20, 1981
    Date of Patent: June 7, 1983
    Assignee: Thomson-CSF Telephone
    Inventors: Bernard Gilles, Jose A. Paulet, Raphael J. S. Roux
  • Patent number: 4386242
    Abstract: Circuitry (100) for providing impedance compensation between a source impedance (501) and a load impedance (505) which is proportional to the source impedance comprises: a pair of directional couplers (200 and 300), each coupler including bidirectional transmitting and receiving paths and a unidirectional path coupling these paths; means (121) for cascading the transmit path of one coupler to the receive path of the other; and unidirectional amplifier (400) for interconnecting the remaining bidirectional transmission ports. The impedance match to the source is obtained by adjusting the amplifier gain in correspondence to the number of essentially identical terminations that are bridged to form the load impedance. Means (510-515) sense the number of active terminations and transmit this information to the amplifier so the appropriate gain setting may be established.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: May 31, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Harold Seidel
  • Patent number: 4385212
    Abstract: An expandable telephone housing has been developed which allows for easy lateral expansion. The housing contains front and rear slides and an end cap which is removable. For expansion the end cap is removed exposing a mating mechanism for locking to an expansion housing. The expansion housing contains a face plate having additional lamps or buttons. New, and longer, front and rear slides are positioned along the front and rear edges of the combined housing to secure the now elongated structure. When assembled, the combined housings give the appearance of a single housing. The rear slide may be arranged for securing an auxiliary display unit.
    Type: Grant
    Filed: October 5, 1981
    Date of Patent: May 24, 1983
    Assignee: Bell Telephone Laboratories Incorporated
    Inventor: Daniel W. Tyler
  • Patent number: 4380690
    Abstract: A hybrid circuit, in which the differential output of an amplifier of the four-wire receive port having the differential output of low output impedance is connected to a series-connected circuit composed of a variable impedance circuit and the primary winding of a transformer connected to the two-wire port of the hybrid circuit, and in which the input of an amplifier of the four-wire transmit port of the hybrid circuit having a high input impedance is connected to the node connection of the variable impedance circuit and the primary winding of the transformer. In the case where the impedances of the variable impedance circuit and the transformer are in a state of mutual equilibrium, the neutral point potential of the amplifier of the four-wire receive port is applied as an input to the amplifier of the four-wire transmit port.
    Type: Grant
    Filed: June 29, 1981
    Date of Patent: April 19, 1983
    Assignee: Iwasaki Tsushinki Kabushiki Kaisha
    Inventors: Teruo Matsufuji, Akira Hirato, Yoshihiro Kawada
  • Patent number: 4379209
    Abstract: An audio amplifier having an auxiliary terminal for connection of a feedback line to the grounded terminal of a loudspeaker and including a circuit for protection against voltage overload on the amplifier and loudspeaker if the auxiliary terminal is inadvertently connected to the ungrounded terminal of the loudspeaker, or in case of malfunction of the feedback circuit. The protection circuit includes a signal generator activated by the closing of a power switch for producing a check signal for circuiting through the terminals of the loudspeaker to the auxiliary terminal and a controller sensitive to the voltage at the auxiliary terminal for controlling a switch for disconnecting the feedback line, if the voltage at the auxiliary terminal exceeds a predetermined value.
    Type: Grant
    Filed: November 19, 1980
    Date of Patent: April 5, 1983
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventor: Hideki Sakano
  • Patent number: 4378472
    Abstract: A hybrid circuit arrangement for a telecommunication system includes a transformer having a first and a second partial winding connected to a two-wire line. Third and fourth partial windings having a grounded junction are coupled to a receiving branch and a transmitting branch of a four-wire transmission line, respectively. A power supply bridge having a resultant supply resistor and a supply capacitor is inserted between the first two partial windings. The total inductance of these windings equals the supply capacitor value times the squared supply resistor value. An ohmic load resistor terminating the receiving branch has a resistance according to a specific relationship depending on the ratio of turns of the third partial winding divided by those of the first and second partial windings.
    Type: Grant
    Filed: March 6, 1980
    Date of Patent: March 29, 1983
    Assignee: Siemens Aktiengesellschaft
    Inventor: Robert Lechner
  • Patent number: 4377730
    Abstract: A cancellation circuit which may be utilized in a subscriber loop interface circuit to allow a tone to be supplied in the receive path of the hybrid circuit to be received by the calling subscriber and for cancelling said tone from being transmitted to a called subscriber that is coupled via a carrier channel to the hybrid circuit. The cancellation circuit comprises circuitry responsive to the tone appearing on the transmit path for supplying in-phase and quadrature phase signals at the frequency of this tone to cancel the same to prohibit transmission thereof while simultaneously varying the output impedance of the hybrid circuit at the frequency of the applied tone.
    Type: Grant
    Filed: June 8, 1981
    Date of Patent: March 22, 1983
    Assignee: Motorola, Inc.
    Inventors: Michael J. Gay, W. David Pace
  • Patent number: 4375584
    Abstract: A modular telephone keyset instrument is arranged within a rectangular casing having indentations in the top for receiving a telephone handset. Electrical (electronic) circuits are provided on a mother PC board, a daughter PC board and a key switch PC board, stacked within the housing from bottom to top, respectively. The daughter and keyset PC boards are connected to the mother PC board by ribbon cables. A hook switch, mounted on and attached to the daughter PC board extends through one of the indentations in the top to sense whether the telephone handset is placed in the indentations.
    Type: Grant
    Filed: October 6, 1980
    Date of Patent: March 1, 1983
    Assignee: Siemens Corporation
    Inventors: Deepak Muzumdar, William Levine, Gerry Suarez, Rolf Schneider, Theodore W. Wagner
  • Patent number: 4375015
    Abstract: An improved electronic hybrid circuit or terminating set provides toll-grade interfacing between two and four-wire voice frequency transmission facilities. The terminating set presents a fixed input impedance to, and common mode rejection to longitudinal noise on, the two-wire side of the facility, and either the same or a different fixed impedance at each of the transmit and receive input ports on the four-wire side of the facility.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: February 22, 1983
    Assignee: Tellabs, Inc.
    Inventor: Charles W. Chambers, Jr.
  • Patent number: 4374305
    Abstract: Described is the regeneration of dial pulses in the signalling system CCITT type B. The dial pulses are regenerated by a combined regeneration process comprising a reduced process with two sampling instants (10 ms, 30 ms) and an inverse process with four (anisochronous) sampling instants (10 ms, 30 ms, 52 ms, 72 ms). The reduced process is started by the stop-start transition at the beginning of the first of a series of dial pulses and the inverse process by the start-stop transition which occurs at the end of the series of dial pulses.
    Type: Grant
    Filed: September 26, 1980
    Date of Patent: February 15, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Robert Bodart, Jean-Pierre Werts
  • Patent number: RE31253
    Abstract: An adaptive echo canceller for two-wire, simultaneous two-way data communication at full bandwidth uses Nyquist-interval, rather than baud-interval, processing to achieve independence from timing discrepancies between near-end and far-end terminals. The entire echo signal, and not merely baud-interval samples thereof, is suppressed. The echo canceller is preferably a transversal structure.
    Type: Grant
    Filed: December 23, 1980
    Date of Patent: May 24, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Stephen B. Weinstein