Private branch exchanges for connection to public switched telephone networks run by certain public telecommunication operators. Specification for the procedure for in-service observation of PBXs undergoing type approval.
NORM herausgegeben am 28.10.1990
Designation standards: BS 6450-7:1990
Note: UNGÜLTIG
Publication date standards: 28.10.1990
The number of pages: 14
Approximate weight : 42 g (0.09 lbs)
Country: British technical standard
Kategorie: Technische Normen BS