Abstract: In an electronic inductor circuit, an operational amplifier drives the base of the electronic inductor transistor, and receives negative feedback from the emitter of the transistor. The transistor and operational amplifier combine to form a voltage-controlled current source (VCCS) with respect to the loop current. A voltage divider connected across the rectified Tip and Ring voltage (or another node of the circuit at an equivalent voltage) provides a DC reference to the positive input of the operational amplifier, so that the line current automatically increases with an increase in line voltage. A capacitor couples the transmit signal driver to the positive input of the operational amplifier. This electronic inductor circuit can be driven using a low voltage supply and provides sufficient linearity for high-speed modem applications.

Abstract: A modem interface device is coupled to a computer such that the device is powered via a power signal received from a bus port of the computer, such as a Universal Serial Bus (USB) port, a RS-232 port, or a PS-2 port. The modem interface device has a telephone base connector, a modem connector, a power connector, a two-to-four-wire converter circuit, and a power distribution circuit. The two-to-four-wire converter circuit bidirectionally couples signals between the telephone base connector and the modem connector. The power distribution circuit receives electrical power from the power connector and supplies power to the two-to-four-wire converter circuit.

Abstract: A computer system is used with a telephone that is operable by a user to furnish a predetermined command. The processing unit and a control circuit. The central processing unit is connected to communicate with the interface port, and the control circuit is connected to the telephone. The control circuit is configured to detect the predetermined command and in response to detection of the predetermined command, change a connection status between the telephone and the interface port.

Abstract: A telephone instrument includes a built-in modem device that is connected electrically to a telephone line and to a data network terminal. The modem device can be activated by the data network terminal to establish communication between the data network terminal and an Internet service provider through the telephone line in response to a request to access the Internet from the data network device. A signal coder/decoder in the telephone instrument permits conversion of an outgoing call signal that was picked-up by a handset unit into encoded outgoing call data having a call data format that conforms to voice communications protocol through the Internet service provider. The signal coder/decoder further permits conversion of encoded incoming call data generated by the data network device from an incoming network signal that was received from the Internet service provider into an incoming call signal to be reproduced by the handset unit.

Abstract: A system and method for selecting from a plurality of data service options in a wireless communication system having mobile data service support. The system comprises a terminal device includes a terminal device for originating a call and transmitting and receiving data in accordance with a selected data service option. The terminal device includes a communications interface for inputting a sequence of one or more alpha-numeric characters representing an AT dial command string in order to originate the call and for including information that indicates the selected data service option. The system also includes a communication device, coupled to the terminal device, for interfacing with the wireless communication system and for sending signaling messages to the terminal device. The communication device receives the AT dial command string from the terminal device and examines the contents of the received AT dial command string.

Abstract: A telephone network interface apparatus for use in the subscriber loop of a telephone transmission system, i.e., connected to a non-telephone company owned premise wiring (a consumer household) and a telephone company owned portion of such loop at the junction where the two connect to each other. The apparatus provides limited access to the open top base member, i.e., only a portion of the base member is made readily accessible to the consumer by providing a cover readily opened by him and a shield cover which may be readily opened by telephone company employees in order to provide access to electronic components owned by the telephone company disposed with the base member. Both covers are free of apertures communicating with the inside of he base member. The device includes a base structure which includes a first and second set of terminals and a plug and receptacle arrangement for disconnecting the premises wiring from the telephone transmission system.

Abstract: A signal processing apparatus having a register unit with the number of bits required for signal processing, which is not larger than predetermined number of bits, and comprising a ROM which inputs, as an address signal, an output signal from the register unit or an input signal to the signal processing apparatus, and uses an input signal to the register unit as a part of an output signal from the ROM. This makes it possible to greatly reduce the cost of a system which executes complex processing yet requires a reduced number of bits in the input signals and a reduced number of bits for the register that is essentially required by reducing the amount of signal processing and the number of electric components, to greatly improve the quality of the apparatus accompanying the reduction in the number of electric components, and to cheaply increase the signal processing functions without decreasing the processing speed.

Abstract: A keypad for a portable telephone and manufacturing method thereof is disclosed. The method comprises the steps of printing characters on a transparent, planar film; pre-forming the planar film through a pressing process such that the planar film has a predetermined shape including a plurality of depressions; punching slits in the pressed planar film around the depressions; filling liquid silicone rubber into the depressions of the pressed planar film; forming a keypad by pressing the silicon rubber in a metal mold so as to fabricate an integrated keypad in which keys are interconnected; and trimming an outer periphery of the formed keypad according to a predetermined keypad shape.

Abstract: An encryption device for a telephone having a handset and a base unit is disclosed. The device includes a handset interface, a first converter, an encryption processor, a second converter, and a host interface. The handset interface receives analog output signals from the handset. The first converter converts the analog output signals into digital output signals. The encryption processor includes a compressor, a key manager, an encryptor, and a modulator. The key manager generates key material for encrypting the digital output signals. The compressor compresses the digital output signals, the encryptor encrypts the digital output signals based on the key material, and the modulator modulates the encrypted digital output signals. The second converter converts the encrypted digital output signals into encrypted analog output signals. The host interface receives the encrypted analog output signals from the encryption processor, and forwards the encrypted analog output signals to the base unit.

Abstract: An emergency reporting apparatus for a vehicle includes a memory storing information representing a telephone number of an emergency report receiving center. Connection with the emergency report receiving center is implemented in response to the telephone number represented by the information in the memory. An emergency can be reported to the emergency report receiving center. The information in the memory can be updated to change the telephone number represented thereby.

Abstract: The present invention is directed to a novel system and method for connecting and interfacing a communications device, such as a modem, to a two-wire telephone line via a telephone base set, thereby allowing for data or voice communications on the telephone line. The modem and the telephone base are interconnected by way of an interface adapter, which also provides a connector for connecting the telephone's handset. Relay circuitry present within the interface adapter automatically switches between a data mode state and a voice mode state, depending upon what kind of communication is desired over the telephone line. In a preferred embodiment, the system also includes a cable detector circuit that allows the modem to automatically detect when it is connected to a telephone base by way of the interface adapter. Also disclosed, is a novel method for programming the host computer connected to the modem, and the communication processor located on the modem.

Abstract: An audio communications device adapter connects a plurality of audio communications devices, such as headsets, to digital data paths, such as T1 or E1 data paths in a telephony system. The adapter comprises one or more analog audio signal connectors that connect to analog audio signal paths coupled to the audio communications devices for receiving and transmitting outgoing and incoming analog audio signals. The adapter also includes a digital data connector for connecting to digital data paths to transmit and receive outgoing and incoming digital data streams containing digital encoded audio signal data. A digital data formatter coupled to the digital data connector extracts the incoming digital encoded audio signal data from the incoming digital data stream and formats the outgoing digital encoded audio signal data. The digital data formatter includes a T1 framer and interface, serial PROMs for programming the T1 framer and interface, timing and control circuits, and a T1 transmit equalizer.

Abstract: An extension-in-use exclusion apparatus is for use in a telephone system. The system has a telephone device, a telephone line, and two telephone extensions connected to the line. The apparatus is connected between one extension and the telephone device. The apparatus has an exclusion controller connecting the line to the telephone device when all extensions other than the extension for the telephone device are on-hook and the telephone device extension is off-hook. The exclusion controller does not connect the line to the telephone device when another extension is off-hook and the telephone device is off-hook. A user operable switch can instruct the exclusion controller to connect the line to the telephone device when another extension is off-hook and the telephone device is off-hook. The apparatus automatically returns to exclusion mode when the telephone device returns to off-hook. A by-pass allows FSK signals to pass directly through to the telephone device.

Abstract: A portable electronic device holder having a housing defining a cradle for holding an electronic device, a battery integrally connected with the housing for powering the electronic device in response to placement of the electronic device within the cradle of the housing, and a connection for interconnecting power circuitry of the electronic device with the battery. The housing further includes a charger for charging the battery incorporated therewithin. The holder may also include an attachment for attaching the housing to a user, such as, for example, a belt clip.

Abstract: An automatic call-back device notifies a subscriber when a called party's telephone station is no longer busy. When the subscriber calls a called party and the called party's telephone station is busy, the automatic call-back device offers the subscriber call-back options for calling the subscriber when the called party's telephone station is no longer busy. If selected, the automatic call-back device monitors the called party's telephone station for an on-hook signal, for example. When the called party goes on-hook, the automatic call-back device calls the called party and the subscriber and connects the subscriber and the called party in a call. If multiple subscribers call the same called party, the automatic call-back device stores an identifier corresponding to each subscriber in a call-back list based on when each subscriber called the called party. When the called party goes on-hook, the automatic call-back device contacts the first subscriber in the call-back list (i.e.

Abstract: A call defeat device to prevent calling unauthorized numbers, such as long distance, 1-900 etc., which is adapted to prevent a caller from successfully dialing one or more predetermined digit strings on a touch tone telephone connected to a given telephone line by apparatus including a touch tone decoder coupled to the telephone line and a microprocessor/memory for storing and issuing predetermined unauthorized digit strings, if dialed on the telephone, designates that the call is to be defeated. A comparator compares each digit string dialed on the telephone to the predetermined digit strings, and, if a match is sensed, a dialer sends onto the telephone line at least one DTMF digit, such as a "#", which will defeat the call in progress.

Abstract: A modular plug which has an insulative housing comprising a front wall, a rear wall, a top wall, a bottom wall and a pair of lateral walls which are perpendicularly interposed between the top two bottom walls. There are a plurality of front longitudinal terminal receiving slots in the top wall adjacent the front wall. There is also a cable receiving cavity in the rear wall. A plurality of rear longitudinal terminal contact receiving slots are in the top wall and between the front longitudinal terminal contact receiving slots and the rear wall. A medial component housing cavity is interposed between the front longitudinal terminal contact receiving slots and the rear longitudinal terminal contact receiving slots. There is also a first plurality of conductors, each of which extends from the rear wall of the jack to adjacent a different one of said rear longitudinal contact terminal receiving slots.

Abstract: The present invention relates to a telephone with an interface connection with the television, which includes a basic telephone set, central processing unit (CPU), display controller and a control program. The control program controls the whole operating procedures of the telephone of the invention. Under the operating procedures, the CPU transmits the phone-call information received by the basic telephone set to the display controller. In accordance to the received information, the display controller generates and transports a corresponding signal to a television. With the telephone of the invention, the information of a telephone call can be displayed in a television.

Abstract: A phone patch 26 for interfacing between a radio 12 and a telephone network 32 includes means for electrically coupling audio signals between the radio 12 and the telephone network 32. A monitoring means is operationally coupled to the coupling means and may adjust the audio signals through operator controls 42. The monitoring means allows an operator to communicate with both the radio and telephone user and modify the audio signals to provide sufficient volume without overmodulation.

Abstract: A communication apparatus has a power saving stand-by mode for reducing power consumption during stand-by and a non-ringing call receiving mode for communication without ringing an attached telephone set at the arrival of a call. In the power saving stand-by mode, an operation state of a relay for attaining the non-ringing call receiving mode is held by a stand-by power supply to render both modes compatible to each other.

Abstract: A telephone silencing system is provided for use with at least one telephone receiver and an external telephone line electrically connected with the telephone receiver. This system includes a switch electrically connected in series between the telephone line and the telephone receiver. The switch is actuatable between a closed position, in which the telephone receiver(s) is connected to the telephone line, and an open position, in which the telephone receiver(s) is electrically disconnected with the telephone line. A receiver is operatively connected with the switch actuated between a closed and open position in response to a preset signal. A transmitter, in turn, when actuated, generates the preset signal to the receiver to thereby actuate the switch between its closed and open position.

Abstract: The present invention relates to an adaptive telephone interface for use in a telephone apparatus comprising a telephone terminal including signal amplifier means, and audio/input device. The telephone interface is disposable between the terminal and the audio/input device, and comprises a processor for generating a test signal and sending this to the terminal at a plurality of different amplitudes. The processor is further formed and arranged for monitoring signals returned from the terminal by means of sidetone coupling, so as to identify the test signal amplitude at which clipping of at least part of the test signal occurs, and consequentially adjusting the amplification by the interface of a signal received from the audio input device, before sending it on to the terminal so as to avoid substantially clipping thereof by the terminal signal amplifier means in use of the telephone apparatus.

Abstract: A method for performing audio input/output through a telephone in a computer system, wherein a telephony driver and an audio driver and an audio task executing on a digital signal processing subsystem of the computer system perform sound sample data conversion to a standard data format and perform sample rate conversion and stereo to mono conversion for digital telephone compatibility.

Abstract: A network termination equipment for connecting telecommunications apparatus to a telecommunications network has operative elements to perform terminal functions. The termination may perform line diagnostic functions, remote telemetry functions. Alternative front plates are connectable to intermediate plate to configure the termination equipment to perform the different functions necessary for additional services or to control access to the network to authorized users only.

Abstract: A host telephone is connected by an interface to an accessory item. The accessory item is, for example, a cordless headset, a headset amplifier, a remote telephone dialing device, a cordless handset or some other device which is connected to a telephone. Two connectors are used to connect the host telephone to the interface. A first connector provides a standard headset connection to the host. The first connector propagates four signals: a transmit audio signal, a transmit return signal, a receive audio signal and a receive return signal. A second connector provides a propagation media for additional signals. The additional signals provide additional communication links between the host telephone and the accessory item.

Abstract: A system for generating aural announcements of incoming calls within a premises has a premises phone connected within a premises phone line that forms first and second communication channels. The first communication channel is adapted for connection and communication to a phone network. An announcement controller is connected within the phone line and generates aural announcement signals along the second communication channel to a speaker which plays corresponding aural announcements. A switch may be operatively connected between the premises phone and announcement controller and switches the announcement controller into the second communication channel for transmitting aural announcement signals to a premises phone via the switch.

Abstract: A shunted modular jack is provided with a shunting module mounted against a rear face of the modular jack. The shunting module comprises a housing and shunting contacts having pairs of shunting contact portions. The shunting contacts are mounted to the housing at different levels to enable a large plurality of shunting combinations, and easy and cost-effective alteration of shunting configurations without alteration of the modular jack housing.

Abstract: A circuit for providing an interface between a telephone set and a modem having voice processing capabilities that allows digitization of the voice to occur and provides an improved capability for the detection of a signal indicating a transfer from voice mode to data mode. A typical telephone interface consists of a `2 wire system` on which both the incoming and outgoing signals are carried simultaneously. These two signals need to be separated in order to digitize the outgoing signal. This is done using a hybrid transformer network that attempts to subtract the incoming signal from the outgoing signal. To switch from voice mode to data mode, it is necessary to `listen` for the data tones while a voice call is in progress. These tones are sent by a remote modem as a signal for the local modem to switch into data mode. These tones may be received at a very low level which can prevent the tone detection circuitry from properly functioning.

Abstract: Network interface apparatus for being mounted on a connector block and for interconnecting at least one incoming telephone company line to at least one telephone subscriber line and for providing a response to signals carried by the incoming telephone company line such as a response to test signals carried by the incoming telephone line to locate a fault as being on the telephone central office side of the apparatus or on the telephone subscriber side of the apparatus.

Abstract: Module for being mounted to telephone network interface apparatus and for interconnecting and disconnecting a subscriber premises line to and from an incoming telephone company line and for providing a demarcation point between the lines for facilitating the determination of whether a fault exists on the subscriber premises line side of the module or on the incoming telephone company line side of the module, the module includes a base provided with a first latch, a jack provided on the base for being connected to the incoming telephone company line, subscriber terminals provided on the base for being connected to the subscriber premises line, a cover mounted pivotally to the base and provided with a second latch which is resilient and for releasably engaging the first latch to releasably latch the cover to the base upon the cover being pivoted toward said base sufficiently to engage the first and second latching means.

Abstract: A modular jack includes a filter circuit for each of the transmit and receive pins in order to shape the signal waveforms, isolate the user from the line, and filter out both common and differential mode noise in high-speed communications systems, such as 10BASE-T, 100BASE-T, token ring and ATM applications. The manufacture of the modular jack of the present invention is simplified by the design of the components which make up the modular jack assembly. More specifically, the contact pins of the modular jack are divided into a contact pin array and a mounting pin array. The two pin arrays are electrically coupled through a printed circuit board which carries the two filters. A platform formed on the mounting pin array facilitates the attachment of the printed circuit board during manufacture.

Abstract: A 4-pin telephone jack adapter which alters the pin configuration of a 4-pin telephone jack such that the phone line connected to the two outer pins of the jack is connected to the two inner pins of the adapter and be accessible to a one-line telephone set. The 4-pin telephone jack adapter can have two receptacle one of which alters the pin configuration of a 4-pin telephone jack while the other has the same pin configuration. With such an adapter, two one-line telephone sets can separately access to two phone lines connected to a 4-pin telephone jack. The same pin connection can be applied to a telephone cable coupler and a telephone extension cable.

Abstract: A multi-media modem is used to provide a security access arrangement that identifies a calling party to a computer system. In particular, a multi-media modem couples both an analog channel and a data channel to the computer system. The analog channel conveys the calling party's identification information, while the data channel conveys a data signal from the calling party. The computer system verifies the calling party's identification information communicated over the analog channel and, if the verification is successful, immediately establishes, or continues, data communications with the calling party over the data channel.

Abstract: An interface between an alternating voice-data (AVD) modem and a telephone that allows the modem to be connected to a PBX or office-type telephone system without using special software. The user speaks and listens through the telephone handset, which is disconnected from the telephone base and connected to the interface. The interface provides an impedance across the modem "Phone" connection. The impedance simulates the off-hook condition that would normally (i.e., when the modem is connected in the conventional manner to a non-PBX telephone) be provided by the non-PBX telephone and that, absent disabling the requirement by special software, the modem requires in order to properly switch between voice mode and data mode. The interface monitors the modem "Line" connection to detect whether the modem is in an off-hook state or an on-hook state. A compensation circuit minimizes attenuation of the wake-up tone by the impedance across the "Line" connection.

Abstract: A subscriber module (40) for a network interface device (10) having a jack (100) defining a plug-receiving cavity (102) thereinto, and having a plug (50) insertable into the jack. The plug includes a plurality of interconnecting contacts (56) disposed at a mating end (58) thereof, and the jack includes first and second contacts (106, 112) secured within the plug-receiving cavity in spaced-apart disconnected pairs. Insertion of plug (50) into jack (100) moves interconnecting contacts (56) between associated ones of first and second contacts (106, 112) to electrically interconnect them, completing otherwise unconnected circuits between the distribution cable and the subscriber premise wiring. Preferably plug (50) includes a sealing member (74) therearound to seal the mating interface when plug (50) is inserted into jack (100).

Abstract: An on-line indicator (40) for the multipurpose headset amplifier comprises a holder in two parts (45) arranged to be snapped onto the ascending, holder (10) which is mounted on the housing (5) of the multipurpose headset amplifier. The on-line indicator has a rotatable indicator or light emitting diode (41) which is coupled to the multipurpose headset amplifier by means of a cable (42). The light diode will light up when the headset is in use to indicate to others that the user of the headset is on the line.

Abstract: A subscriber module (40) for a network interface device (10) having a jack (100) defining a plug-receiving cavity (102) thereinto, and having a plug (50) insertable into the jack. The plug includes a plurality of interconnecting contacts (56) disposed at a mating end (58) thereof, and the jack includes first and second contacts (106,112) secured within the plug-receiving cavity in spaced-apart disconnected pairs. Insertion of plug (50) into jack (100) moves interconnecting contacts (56) between associated ones of first and second contacts (106,112) to electrically interconnect them, completing otherwise unconnected circuits between the distribution cable and the subscriber premise wiring. Preferably plug (50) includes a sealing member (74) therearound to seal the mating interface when plug (50) is inserted into jack (100).

Abstract: A security node disposed in the telecommunications network connecting calling and called parties transforms information (which can be voice, data, facsimile, video and other types of calls or messages) encrypted in a first format to (a) encrypted information in a different format or to (b) non-encrypted information, and vice-versa. The node is accessible from any location connected to the network. By routing calls or messages originated by the calling party and destined for the called party via the security node, and providing appropriate control signals to the node, the information may be encrypted only over a portion of the transmission path between the parties, and clear over the remainder of the transmission path. Alternatively, the information may be encrypted in different portions of the path using different encryption algorithms.

Abstract: An interactive voice communication terminal (10) provides alpha and numeric characters transmitted from a DTMF generator (36) to access a database by interfacing with the mouthpiece (24) of a telephone handset (26) via a transducer (22). A keypad (14) is operable to allow selection of one of multiple characters associated with alpha characters and numeric characters. A table of DTMF strings associated with each key is stored in a memory (34). In response to depression of a key on the keypad (14), a centralized controller (32) controls the DTMF generator (36) to output the sequence associated with the depressed key that was stored in the memory (34) to transducer (22) via a driver (38). The tables in the memory (34) can be a combination of DTMF sequences for alpha characters and single number sequences for numerical sequences or they can be fixed-length sequences for all numerical and alpha characters.

Abstract: A traditional modem includes a data access arrangement circuit located between the computer and the RJ11 connector. An alternate connection is made from this data access arrangement circuit to an input of a carbon microphone interface circuit. This carbon microphone interface circuit includes a galvanic isolation circuit and an impedance matching circuit. The input to the carbon microphone interface circuit is thus transformed to a format which is compatible with a traditional carbon microphone found in the handset of practically all telephones. Therefore, the output of the carbon microphone interface circuit can be directly connected to the handset of a telephone (or other carbon microphone audio terminal device), independent of the location or type of subscriber interface at the wall jack.

Abstract: An interface device between a public telephone (9) and an external terminal (14), the public telephone (9) having a control circuit (10) connected to a telephone line (20) and the interface device having a connector (15) accessible to the user. A switching circuit (22) makes it possible to switch the line (20) either to the control circuit of the public telephone (10), or to a connector control circuit. An information circuit of a connection of the external terminal is in the connector, a first electrical insulation module (21) is located between a connector control circuit and the switching circuit (22), a second electrical insulation module (19) is between a connector control circuit and the control circuit of the public telephone (9) and a control circuit of the connector (16).

Abstract: This invention discloses a network termination module comprising a base structure having a means for grounding. Mounted on the base structure is an intermediate structure which contains a telephone jack and also a pair of line terminals for connection to telephone company wiring. A terminal strip is mounted above the intermediate structure, the terminal strip containing subscriber terminals for connection to a subscriber's wiring. Mounted above the terminal strip is an openable cover containing a telephone plug which mates with the telephone jack. The line terminals are electrically connected to the telephone jack. There is a protector element disposed in the base structure which is electrically connected to the means for grounding.

Abstract: A method and apparatus for recording and playing back a sales presentation is disclosed. A telephone interface device is connected to a telephone base, handset and recorder to permit recordation of a sales message using the telephone mouth piece as the recorder microphone. The recorded message has the same sound quality when transmitted over the phone lines as does a normal, live transmission. Transit to and from live and recorded voice is undetected by the party hearing the sales presentation over the phone. Use of the telephone interface device and the recorded sales presentation precludes fatigue and discouragement on the part of the telemarketing sales representative in the face of repeated repetitions of the same sales message and frequent rejections by prospective customers.

Abstract: An emulator circuit is provided for allowing a data/fax/voice modem, a host computer, and a telephone headset to emulate the functions of a telephone. For voice communication, the emulator circuit connects the telephone headset to the telephone line. For automated data/fax/voice communications, the emulator circuit connects the modem to the telephone line. Two specific embodiments of the emulator circuit are described. In one, the emulator circuit is configured from analog circuit components connected to the modem. In the other, the emulator circuit is an integrated circuit component of the modem. In both embodiments, the provision of the emulator circuit obviates the need to provide a separate telephone for handling voice telephone conversations.

Abstract: A telephone answering device for permitting a person to switch an incoming telephone call to a message recording or answering machine for taking or recording a message from a caller onto at least one cassette of the message recording or answering machine. This device includes a telephone instrument, at least one message recording or answering machine, and a person actuated switch. The person actuated switch has a first "normal" position to permit a person to receive calls using the telephone instrument and a second position for permitting a person to switch the caller to the message recording or answering machine after the person has initially spoken to the caller.

Abstract: An emulator circuit is provided for allowing a data/fax/voice modem, a host computer, and a telephone headset to emulate the functions of a telephone. For voice communications, the emulator circuit connects the telephone headset to a communication device such as a telephone line or cellular radio. For automated data/fax/voice communications, the emulator circuit connects the modem to the communication device. Two specific embodiments of the emulator circuit are described. In one, the emulator circuit is configured from analog circuit components connected to the modem. In the other, the emulator circuit is an integrated circuit component of the modem. In both embodiments, the provision of the emulator circuit obviates the need to provide a separate telephone for handling voice telephone conversations and other communications through said telephone line, cellular radio.

Abstract: An apparatus for permitting hands-free operation of a mobile telephone unit in a car includes a wireless microphone transmitter for generating wireless outgoing signals corresponding to sounds picked up in the passenger room of a car, and a main terminal which has a terminal housing with one end adapted to be inserted into a cigarette lighter socket of the car. A receiver circuit is disposed in the terminal housing and is capable of receiving the wireless outgoing signals from the transmitter. A telephone connector is adapted to be connected electrically to the mobile telephone unit and enables the mobile telephone unit to receive the wireless outgoing signals from the receiver circuit and transmit wirelessly the wireless outgoing signals. Wireless incoming signals received by the mobile telephone unit are received by a loudspeaker in the terminal housing. The loudspeaker generates an acoustic output corresponding to the wireless incoming signals.

Abstract: An interface between a telephone handset and an external device having both data and audio inputs and outputs, such as a voice-over-data modem, allows a user to speak and listen through the handset of the telephone instrument. The interface also allows a voice-over-data modem to be connected to a PBX-type telephone system. The interface includes a filter circuit that allows the audio-frequency signal generated by the handset microphone to pass through to the external device while blocking DC along that path. The circuit also allows the DC bias voltage provided by the telephone base to pass through to the handset microphone while blocking audio-frequency signals on that path. The interface may also include a switching circuit that forms direct electrical connections between the telephone handset and the telephone base when the external device is not in a mode in which it can communicate data, e.g., when a voice-over-data modem is in an on-hook state.

Abstract: A security node disposed in the telecommunications network connecting calling and called parties transforms information (which can be voice, data, facsimile, video and other types of calls or messages) encrypted in a first format to (a) encrypted information in a different format or to (b) non-encrypted information, and vice-versa. The node is accessible from any location connected to the network. By routing calls or messages originated by the calling party and destined for the called party via the security node, and providing appropriate control signals to the node, the information may be encrypted only over a portion of the transmission path between the parties, and clear over the remainder of the transmission path. Alternatively, the information may be encrypted in different portions of the path using different encryption algorithms.

Abstract: An attended messaging system having an audio message recording and playback device connected in series between a telephone base unit and a telephone receiver handset or headset. The recording and playback device includes a solid-state audio memory chip for storing a message and pairs of operational amplifiers connecting the memory chip of the recoding and playback device with the telephone base unit and with the speaker and microphone of the telephone receiver handset or headset in a differential circuit of audio signal channels. The recording and playback device is manually-actuable by means of buttons or switches to operate in a recording mode, in which a message spoken into the handset or headset microphone is stored in the audio memory chip, or in a playback mode, in which the previously recorded message is communicated through the telephone base unit and telephone line to a designated remote telephone station with which audio communication has been established by the telephone base unit.