Essential requirements for terminal equipment intended for connection to 2-wire analogue speechband leased lines of the public telecommunications network— 24 стр.
Apparatus for connection to private circuits run by certain public telecommunication operators, Specification for apparatus for connection to speechband circuits— 46 стр.
Essential requirements for a handset telephony facility provided by terminal equipment intended for direct connection to an analogue interface of the public switched telephone network— 40 стр.
