Abstract: An electronic modular unit such as an integrated semiconductor unit is disclosed. The inventive electronic unit can be bonded to a support or to another modular unit. For this purpose, the inventive unit is provided with projections or recesses so that units can mate with one another. The projections may be formed by an etching process. Electrical connections as well as mechanical connections between units may be achieved using the projections and recesses.

Abstract: A video conference installation has transmission and reception devices for handling audio and video signals from a plurality of subscriber points via a shared processor which assigns individual subscriber units to the subscriber points. A digital communication system connects subscriber telephone sets (F) to the shared processor via subscriber circuits (AL) having two utility channels and a signalling channel. Audio is pulse code modulated for transmission over one utility channel and compressed video is transmitted over the other. Each subscriber point has a video monitor (B) and video camera (K). Control symbols (SS, SY) are displayed on the subscriber's monitor via an overlay generator (OG). The subscriber can initiate control and switching actions by pointing to displayed symbols on the screen using a cursor, light pen or position sensitive screen input.

Abstract: A process and apparatus for a voice controlled attenuation adjustment in telephone transmission circuits is disclosed. Signals in the sending and receiving directions are decomposed into sub-band signals in a set of frequency sub-bands. Each frequency sub-band is associated with an attenuation device for each direction of transmission. Depending on the level of activity in each direction in a particular sub-band, the attenuation values of the attenuation devices of that particular sub-band are adjusted. The sub-band signals are then recombined.

Abstract: A handset for telephones and the like has electro-acoustical capsules for hearing and speaking, mounted between an upper housing shell and a lower housing shell of the handset. Each of the capsules is connected to the handset cord by a pair of leads received in cutting clamp connections arranged on the rear sides of the hearing and speaking capsules, the opposed housing shells having projections pushing the leads into the cutting clamps. Preferably, the leads are mounted on a foil having openings for the cutting clamps and the projections, and also openings for guide pins, whereby the leads are guided into the cutting clamps when the upper and lower housing shells are brought together on the leads.

Abstract: A disconnecting distribution frame for a small telephone extension system with a plurality of electrical terminals arranged in pairs, each pair of terminals being equipped with corresponding plug contacts and being electrically interconnectable by means of a coupling plug, is formed from one half of a conventional disconnecting distribution frame which is attached to the carrier of a subassembly rack having a guide strip for a printed circuit board. The other half of the disconnecting distribution frame is formed by plug contacts. These plug contacts are attached to the printed circuit board, which is inserted into the guide and correspond in height to the plug contacts on the carrier and are aligned with these. A coupler plug for making the electrical connection is attached to every two plug pins located opposite one another.

Abstract: In a switching device for power supply to accessories included in a telephone device, from the loop current to the telephone device, a parallel load is connected between the intercom cables for carrying the loop current, a supply current for the accessories being distributed by a current distribution switching section at the output of the parallel load, according to priority classes assigned to the respective accessories. The control device of the telephone has a highest priority, possibly in combination with a speech mode. This control device has a memory for storing the last-dialed telephone number for the purpose of repeated re-dialing. The memory contents are retained for several hours after the device is switched off the cables.

Abstract: A telephone instrument is designed in the shape of an angle, whereby the upper side has a steeper inclination towards the user. The rear wall is at approximately a right angle to the upper side. The bottom side runs at a specific distance, parallel to the upper side and to the rear wall. Since the distance between the upper side and the bottom side is not very great, i.e. since a maximum of only two printed circuit boards can be accommodated one on top of the other in this space, the bottom side below the upper side has a trough which serves both to accommodate an additional printed circuit board and to provide cable entries. This trough does not extend over the total width of the telephone instrument but is narrower. In order to expand the keyboard, one part of the upper side can be moved in the longitudinal direction, away from the user, so that an additional keyboard or indicator device below it is made available.

Abstract: A terminal of a telephone switchboard installation with one dialing and one service and/or input keyboard and one or more indicator device(s) and a cradle for the hand set. The terminal includes, on the upper side of the terminal a sliding part, which is formed by the upper side which accommodates the keyboards and sometimes includes an indicator device. In one position, the sliding part operationalizes an additional keyboard or indicator device which is located beneath it. This additional keyboard may be designed as a targeted dialing key set, an alpha-numerical input keyboard, etc., and in addition, the keyboard may be replaced with a bank of lamps indicating lines in use.

Abstract: A wall exchange for a telephone system having a baseplate affixed to a supporting wall in which the various component parts are attached to one another and to the baseplate by molded snap-in connectors.

Abstract: A spool for a power supply transformer with one flange having attachments for providing the necessary connections to and from the transformer windings and holding fuses in place and another flange having slots for snap-in attachment to a baseplate.

Abstract: A microphone amplifier in a telephone station furnished with current from the telephone network. When a capacitive degenerative feedback is used in the amplifier a certain time has to pass after applying the supply voltage before the operating point of the amplifier is reached because of the charging time of the capacitor. The switching of the supply voltage occurs at the dialing operation at each digit of a dial number since during the transmission period of a digit the handset including the microphone is switched off the subscriber line which carries the current usd for supplying the amplifier with energy. By the use of a special circuit the charging time of the capacitor is shortened drastically.

Abstract: A telephone hook switch having bounce contact spring which is formed like a frame with middle spring blades arched outwardly in opposite directions and attached at their lower ends with the attached lower ends held in a bearing slot of an operation part which connects to a switching balance. The operation part has a slot one one end for bearing onto the bounce contact spring. Several bounce contact springs and the associated outer springs may be combined like a comb over a stamped strip to be cut off after assembling. The operation part may also be formed comb-like of plastic.

Abstract: The switching network having a reversed trunking scheme of a PCM-(pulse code modulated -) exchange is formed by a first (time division) switching stage (A) consisting of individual switching groups (G l to G m) combined into one major switching group (GG), a second (space division) switching Stage (B1) formed by a number of PCM-lines equal to the number of switching groups (G l to G m) within one major switching group (GG), whereby each switching group is connected with a PCM-line in the outgoing direction, whereas a switching group individual multiplexer (M) performing the access of all PCM-lines to each switching group (G) and a third (space division) switching stage (B2) formed by a number of PCM-lines equal to the number of major switching groups (GG), the bitrate on said PCM-lines being a multiple number of the bitrate of the PCM-lines of the second (space division) switching stage.