Stored program controlled digital public exchange
Switching system
Switching system and method for network having a plurality of te
Switching system data inheritance method and system
Switching system reliability
System and method for backup network glare reduction
System and method for integrated telephony switching
System and method for integrated telephony switching
System and method for precise DTMF signal detection
System and method for providing directory assistance information
System for transmitting DTMF signal and communication...
Systems configured to distribute a telephone call,...
Telecommunication signalling arrangement
Telecommunication switching systems with a central switching and
Telecommunications network having successively utilized...
Telephone branch line transmission circuit with blocking capacit
Telephone line circuit having time-shared DTMF receivers
Telephone switching system
Telephonic console with multipersonality control apparatus and m
Telephonic console with programmable nonvolatile personality mem