1332 THE BELL SYSTEM TECHNICAL JOURNAL, NOVEMBER 1954 

 PRESENT RECORDING AND CHARGING METHODS 



Several types of automatic recording equipment are now in servdce in 

 the Bell System. 



Multi-unit registration (zone registration) has been in use for many 

 years in a number of panel and No. 1 crossbar central offices whose rate 

 structure permits bulk Ijilling. This method can be used for calls which 

 cost 6 or less message units for the initial period. Although zone registra- 

 tion is economical, it does not pro\dde a detailed record of each call but 

 merely scores the number of message units on a register associated with 

 the customer's line. 



Remote control zone registration has been serving customers in panel 

 central offices since 1941. It is similar to multi-unit registration, but the 

 timing and register control equipment is located in a tandem office in- 

 stead of in each originating panel central office. 



Automatic ticketing,^ which was developed some years ago for use in 

 step-by-step central offices, does make a record of the details of each 

 customer dialed call. A simple ticket printer is permanently associated 

 ^\dth each outgoing trunk to produce an individual typewritten ticket 

 for each call. Common relay equipment is used to furnish the called num- 

 ber, calling number, etc. to the printer. The information printed on the 

 ticket is in detailed form and is similar to that prepared by the operator 

 in manual operation. It can be used for billing the customer manually 

 either on a detailed or a message unit basis. 



A greatly improved form of recording, the Automatic Message Ac- 

 counting^ (AMA) system, was introduced into the Bell Sj^stem in 1948. 

 In central offices having this equipment, all of the data required for 

 billing of customer dialed calls are automatically perforated in code on 

 paper tapes. These tapes are taken to an accounting center where they 

 are processed by suitable machines to produce customers' bills. The re- 

 cording machines are associated with the transmission circuits onlj^ when 

 required to make a record, one recorder ser^ang up to 100 such circuits. 

 Recorders, together wdth their associated equipment, are installed in each 

 central office arranged for local AMA recording. The information for 

 each call is recorded on the tape in three stages, or entries. The initial 

 entry is recorded after the customer has finished dialing. One time entry 

 is recorded when conversation starts and another when conversation 

 ends. For short-haul calls that are to be billed on a message unit basis, 

 the initial entry contains only the calling office code and telephone num- 

 ber, and the charging rate. This information, together with the duration 

 of the call, is sufficient for determining the charges. On toll calls which 

 are to be billed in detail, the called office and telephone number are also 



