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Fig. 7 The lower cabinet holds three shelf magazines with printed board assemblies — individual external abbreviated dialling. The function is programmed by the operator and can be used by extensions with push-button sets — call waiting function for incoming external calls — direct switching to a loudspeaking telephone. Classification of the extensions Each extension can be allocated individually to one of 12 facility categories and also one or more of four categories for the control of long-distance calls. There is also the possibility of allocating the extensions other facility categories which automatically come into operation when the PABX is set up for night service. Each facility category comprises one or more of the following basic facilities: — open for all automatic outgoing trunk line traffic — open for operator-assisted outgoing and incoming trunk line traffic — open for transferred trunk line traffic — barred for cutting in — open for the call-waiting function initiated by the operator — vacant The relationship between extensions and facility categories is flexible and programmed into the data store from the operator's set or a typewriter terminal. Of the four categories used for the control of long-distance calls, one indicates that calls are permitted within the local area and the other three are used for opening up certain trunk code areas/subscriber numbers. In this way up to 32 directions, which can be defined with a maximum of 8 digits, can be opened. As can be seen from the above, these 32 directions can be divided into a maximum of three groups. Call pick-up This function means that a call to a free extension can be answered from another extension. This is arranged by dialling a special code, which includes the number of the called free extension. External abbreviated dialling ASB 100 offers the possibility of both individual and common external abbreviated dialling. This makes it possible for the extensions to reach certain previously selected subscribers in the national or international network by dialling two or three-digit numbers. This facility can also be used by extensions that are barred for national and international calls. The programming of the subscriber numbers that are to be reached when an abbreviated number is dialled is carried out from the operator's set or a typewriter terminal. The abbreviated numbers can consist of subscriber numbers or a part of these. In the latter case the additional digits required to complete the whole subscriber number can be dialled from the extension. This is an advantage if, for example, it is desired to open a whole or a part of a trunk code area to all extensions, or in the case of traffic to PABXs that are equipped for direct inward dialling. ASB 100 permits the storage of up to 35 common abbreviated numbers in the smaller version and up to 90 in the larger. These numbers can consist of a maximum of 20 digits, where access codes and intermediate tones are also counted as digits. Six individual abbreviated numbers can be allocated to each of a maximum of 10 extensions in the smaller version and 20 in the larger. The individual numbers can consist of a maximum of 12 digits each, where the digits are counted in the same way as for the common abbreviated numbers above. Call waiting function Thisfunction means that when handling an incoming call to an extension that is already busy, the operator can send a short tone to indicate that there is a call waiting. The extension can then take the new call either by finishing off or parking the existing call. Optional facilities The following functions are considered as optional facilities because they require extra equipment. However, the required programs are included in the program store boards in the basic equipment for the exchange. — operator-controlled call metering — through-connection of trunk lines — individual call metering — paging by means of visual or radio signals — junction lines — busy indication panel.
17 Fig. 8 Printed board assembly for a 12x28 switching network matrix Operator's set and operator functions The operator is responsible for a large part of the service offered to the callers. During the design work every effort has therefore been made to provide a functionally correct design for the operator's console. The aim has been to achieve the best possible relation between man and machine, fig. 3. This has led to a minimisation of the number of function buttons and the use of explanatory symbols instead of text. The training of new operators is simplified because the set is equipped with an information panel, in which it is possible to trace the setting up of a call through the exchange. In addition to the facilities ASB 100 offers for the normal handling of calls, functions can also be included that enable the operator to take an active part in the administration of the exchange if desired. These comprise such functions as changing and checking the extension categories and directory numbers, programming of external abbreviated numbers and call forwarding etc. ASB 100 is designed for use with one operator's console. This is usually connected by means of a plug to a wallmounted jack, but can also, for example during the testing stage, be connected to the exchange cabinet. The console can be placed up to 50 m (15 ohms) from the exchange equipment without any extra equipment being required. Mechanical construction Printed board assemblies, shelves and cabinets All components in ASB 100 are mounted on printed boards. These have single or double-sided foil with the exception of the processor boards, which are manufactured using four-layer technique. The printed board assemblies are mounted in 19" shelves. Three such shelves form a triple magazine and constitute one unit with a common rear plane, where all wiring between the assemblies is carried out. The magazines are mounted in cabinets of two different sizes. The racks contain no wiring. All wiring within the magazines is done on the common rear planes of the magazines, and the wiring between magazines and to external units is done with the aid of plug-in, standardized factory-made cables. Power supply ASB 100 is normally equipped with a built-in power unit, which is designed for feeding from the mains and for providing the power needed to operate the exchange. This unit, which is placed at the bottom of the exchange cabinet, converts the a.c. mains voltage to a 48 V d.c. voltage. Installation and testing Because of its compact structure ASB 100 requires comparatively little space. The floor area required is approximately 2 m 2 , which also includes the necessary free space around the exchange. The installation of the exchange itself can be said to comprise mainly three activities: — mounting theexchangeand connecting external units and power — input of the system data — installation testing. During the design of the system and the establishment of the system handling routines the objective has been to reduce the installation work, and thus also the installation time, to a minimum. This has resulted in, for example, the following features: — the exchange can be delivered to the customer complete and tested — all external connections are carried out with standardized cables equipped with plugs — system data can be programmed quickly by means of special commands, which makes it possible to program in "standard data" for all extensions by means of a single command. Hence the installer does not need to program data individually for each extension, only modify data for the extensions where this is necessary — system data can be programmed up to four days before the PABX is put into operation — advanced test and fault localization programs are available if required.
Page 1: ERICSSON REVIEW 1 1978 OPERATIONAL
Page 5 and 6: ERICSSON REVIEW NUMBER 1 • 1978
Page 7 and 8: 3 STEN RIMBLEUS Stockholm Telecommu
Page 9 and 10: Fig. 4 (left) The operation and mai
Page 11 and 12: Types of faults, measures and subsc
Page 13 and 14: 9 ABDULLAH AL-SABEJ Chief Engineer
Page 15 and 16: Stored Program Controlled PABX, ASB
Page 17 and 18: 13 When the receiver is lifted the
Page 19: 15 five such matrices permit connec
Page 23 and 24: Technical data Capacity Number of e
Page 25 and 26: 21 HENNING ANDERSEN VILLYK. PEDERSE
Page 27 and 28: 23 signalling was to be carried out
Page 29 and 30: 25 Fig. 10 Simplified block diagram
Page 31 and 32: Fig. 12 The principle for common tr
Page 33 and 34: PER-ALRIK HALLBERG THORWALD LUNDMAR
Page 35 and 36: 31 Fig. 9 Regulation range for the
Page 37 and 38: Fig. 12 Power feeding of the line r
Page 39 and 40: 35 oscillators also cease operating
Page 41 and 42: Technical data Electrical data Cabl
Page 43 and 44: 39 CHRISTOPHER LORENZ Financial Tim
Page 45 and 46: The Ericsson Group With associated

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