Exchange and conference communication method therefor
Integrated telephone and intercom system
Intercommunication system for telephones
ISDN dual bus extension phone system
Key telephone apparatus
Key telephone management system
Key telephone system
Key telephone system capable of regulating volume of handset
Key telephone system providing selection of key or PBX operation
Key telephone system reading dialing information from a portable
Key telephone system with circuitry for adding a third caller to
Key telephone system with virtual private lines
Key telephone system with virtual private lines
Man-to-machine communication during on-line conversation in keyp
Memory card connectable to a telephone
Method and apparatus for delivering secured telephony...
Method and apparatus for displaying multiple languages in key ph
Method and apparatus for sharing speakerphone processor among mu
Method for controlling and processing an incoming call of a line
Method for printing key telephone designation strips