D.c. compensated subscriber interface transformer for...

D.c. compensation circuit for miniature transformers

Data access arrangement

Data adapter

Data base auto bill calling using ccis direct signaling

Data base communication call processing method

Data call transfer

Data call transfer preindication

Data capture arrangement for a conference circuit

Data circuit-terminating equipment with power source device...

Data collection network aparatus and method

Data communication apparatus

Data communication system

Data communication system

Data communications device to selectively operate as an...

Data conference arrangement

Data conference system

Data conferencing between remotely located participants

Data dial system and method

Data distribution network and high pass bridging filter or...