Private branch exchanges for connection to public switched telephone networks run by certain public telecommunication operators.Facilities on private branch exchanges. Specification for facilities on private branch exchanges with terminating stations treated as an entirety.
NORMA vydaná dňa 30.9.1988
Označenie normy: BS 6450-5-5.1:1984
Poznámka: NEPLATNÁ
Dátum vydania normy: 30.9.1988
Počet strán: 40
Približná hmotnosť: 120 g (0.26 libier)
Krajina: Britská technická norma
Kategória: Technické normy BS