Abstract: A method of arbitration for transmit mode access to the synchronous transmission medium of a distributed switching network whose architecture is based on a transmission medium time-shared between different stations, in which carries information in repetitive time positions, and in which a nominal time position being assigned on the basis of predetermined access criteria to respective stations communicating within the network, and spillover of stations outside the nominal time positions thus assigned is allowed. The arbitration method allocates an increasing access priority for an increasing seniority due to such spillover.

Abstract: A clutch and brake mechanism for a mechanical drive of print drum in a franking machine is disclosed which utilizes a clutch and brake operated by means of electric potentials applied across an electro-rheological fluid. Elements of the clutch and brake are formed with annular walls which are interposed to form opposed electrodes between which the electro-rheological fluid is contained. Application of electric potentials to the fluid is controlled by a microprocessor.

Abstract: Central office line interface circuit connecting a private telephone installation to a local central office. The central office line interface circuit includes a twin-loop line current polarity detector including a first optocoupler (57) for signalling polarity reversal, a transmission bridge (22) including a line loopback circuit operating via a second optocoupler (74) and provided with regulator and blocking means; it further comprises simplified tone and charging pulse detectors (24, 18).

Abstract: A postage stamp dispenser receives a cassette of postage tape which has marks along its length representing postage value. When a stamp is to be dispensed, the dispenser feeds a length of tape corresponding to the required postage value and prints information such as the postage value and date on the tape. The dispenser may mark the tape with a fuorescent stripe to assist cancellation equipment to locate the stamp. The tape is provided in lengths of known value and the dispenser may provide an indication of thhe value of tape remaining unused in the cassette.

Abstract: A franking machine module is provided with one or more selectively operated mail item feed modules to feed items such as envelopes or labels from hoppers in the feed modules to the franking module. The modules are constructed with common interfaces whereby a number of feed modules may be arranged side by side such that mechanical and electrical drive is transmitted from one module to its adjacent module and feed paths of the modules are co-planar to permit items to be fed into and along a common feed path.

Abstract: A franking machine is disclosed in which the accounting and control circuits of the meter are housed in a secure housing and a printing device for printing a franking impression is located exterior to the secure housing and is connected to the accounting and control circuits. Strings of print data sent to the printing device are returned in a succeeding print cycle to a check circuit in the housing to check integrity of the print data received by the printing device. If desired the print data strings may include a security code. In order to detect if the printing device has been disconnected from the meter, the meter includes a circuit to send a pulse train to the printing device via the connection for print data and to receive a pulse train from the printing device. The circuit compares the pulse trains and if the comparison is unsuccessful inhibits further franking operations.

Abstract: Method and device for managing access to the transmission medium of a multiservice distributed switching network adapted to switch traffic in synchronous circuit-switched mode and in synchronous or asynchronous packet-switched mode, the architecture of the network being based on a transmission medium time-shared between different stations characterized in that: (1) the transmission medium is synchronous and structured in frames in turn structured in time slots in turn structured in time cells, the latter being sized to contain a communication entity which can be either a circuit-switched cell or a segmented packet-switched cell, (2) an ideal time slot for access to the transmission medium in packet-switched mode is assigned to the respective stations communicating within the network, and (3) in each time cell and for all stations transmission medium access arbitration is applied to procure priority access to this medium for circuit-switched cells available at this time in any station.

Abstract: Interface for transmit and receive mode access to the synchronous transmission medium of a distributed switching network. This interface for transmit and receive mode access to the synchronous transmission medium of a distributed switching system, the architecture of the network being based on a transmission medium time-shared between stations and each station comprising a device for determining the time positions corresponding to data to write to or to read from the medium, comprises in each station, for each transmission direction, a pair of memories one of which respectively accesses said medium in transmit mode and in receive mode synchronously with the presentation of the time positions to the medium while the other is respectively written or read under the control of the time position determining device, and vice versa.

Abstract: A device for dissipating heat for a surface mount component assembled onto a printed circuit board is made up by a metallic plate deposited on the rear of the substrate under the surface mount component. A thermal coupling device is made up by a small heat collecting plate provided on the front side of the substrate and the actual substrate. The heat collecting plate also performs an electro-magnetic shielding function and is advantageously constituted either by the shielding plate normally provided for this purpose or by an extension thereof.

Abstract: An auto-answer videotex terminal includes data signal transmission and processing circuits and an isolating transformer between them and a telephone network. It also includes circuits for detecting and recognizing the ringing signal from the network which are connected to the network by the isolating transformer for the data signal circuits. A capacitor and an attenuator resistor appropriate to the frequency and the level of the ringing signal transmitted by the network are associated with the data signal circuits. Further, selectively operated circuits bypass the attenuator resistor and reduce the impedance of the capacitor when the ringing signal is recognized.

Abstract: A stamp printing machine has print drum carrying print wheels which are settable by push buttons to print a selected value of postage charge. The drum is driven by a mechanical device such as tensator spring motor. The motor is manually primed and a trip lever operated by insertion of mail item releases the print drum to rotate through one revolution to print the stamp on the mail item. The stamp machine may include a calculator on which the postage value may be manually entered. Electrical contacts operated by the rotation of the drum are connected across the M+ button of the calculator to add the postage amount to its memory.

Abstract: A construction of thermal print head is disclosed in which a common support includes a plurality of substrates on which selectively heatable print elements of a plurality of print heads are carried. The substrates are arranged in spaced parallel relation such as to permit deposition of conductors and insulation layers on a face of the substrates. Print element selection and drive circuits may be mounted on the substrates and a printed circuit multi-conductor ribbon cable provides connections to the print heads. The print heads print serially on an item and may be operated to print different portions of a print impression in the same color with one print ribbon or may print differently colored portions with different colored ribbons. The thermal print head may be used for printing a franking impression in a postage franking meter.

Abstract: A method of franking mail items is disclosed in which the franking impression includes a machine readable portion and a visually readable portion. The machine readable portion comprises a data block including at least a postage charge and a pseudo-random number and the data block is encrypted prior to printing. During printing of the franking impression, at least a part of the machine readable portion is read and compared with the data block intended to be printed. If the comparison is satisfactory the printing operation is continued to print the visually readable portion. The pseudo-random number is changed for each franking transaction which may be each item or batch of items. The machine readable portion is read at a mail handling centre to provide an input to a postage charging and accounting function.

Abstract: First and second telephone handsets or headsets are used to form a continuity test set providing voice communication. The telephone handsets are modified to connect the transmitter and receiver elements in series with test leads and current-limiting resistors. Connectors are provided at the ends of the test leads, and one of said handsets is provided with a battery to establish a loop current. LEDs are disposed in selected test leads to provide a visual indication of the flow of loop current, which is established when the connectors are attached to common conductors at the remote ends of a multi-conductor cable or conduit.

Abstract: A franking machine is disclosed in which printing of a franking impression is effected by exposing a layer of micro-capsules containing ink to light to thereby cause hardening of the exposed micro-capsules and then subjecting the layer to pressure to rupture the un-exposed micro-capsules in the presence of a developer with which the ink reacts to become visible. The layer of micro-capsules may be coated on envelopes or label tape during manufacture or by coating means in the franking machine. The developer may be applied as a coating in a similar manner. Alternatively one or both the micro-capsules and the developer may be carried on a transfer film brought into contact under pressure with a mail item after exposure of the film.

Abstract: A thermal transfer printing device for a franking machine uses a multi-strike thermal transfer ribbon. Mail items are fed to the printing device and frictional engagement between the mail item and the ribbon during a printing operation draws ribbon from a supply spool. After completion of the printing operation, the mail item is separated from the ribbon and the ribbon is partially rewound onto the supply spool so that each portion of the ribbon is used progressively a number of times. An encoder disc on the supply spool shaft generates signals indicative of the length of ribbon drawn from and rewound onto the spool to control rewinding of the ribbon.

Abstract: A franking machine is disclosed which has a thermal printer for printing variable and non-variable information at a single print station. The non-variable information is printed by thermal print elements having a form corresponding to the information pattern and the variable information is printed by arrays of selectable print elements. The elements are preferably heated by passing electric current through the elements. Alternatively, the elements for non-variable information may be heated from a heated substrate.

Abstract: An information transport system for conveying information between a franking meter machine and a Post Office equipment includes a unit having a non-volatile read/write memory which may consist of an EEPROM which can be transported between the meter and the equipment. When the unit is inserted in the franking machine a transaction code is verified by comparison with a registered code and information transfer is effected. The machine then generates a new code and stores it in a register. Upon return of the unit to the Post Office, the equipment responds to the transaction code stored in the unit to generate a new code corresponding to the new code generated and stored in the meter machine.