Key telephone set with voice switching and direct station...
Key telephone switching apparatus and method for...
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system
Key telephone system and interface unit for key telephone
Key telephone system and main unit thereof
Key telephone system call signaling and station set data...
Key telephone system capable of displaying a plurality of...
Key telephone system capable of regulating volume of handset
Key telephone system capable of simulation by button operations
Key telephone system for subscribers
Key telephone system having wideband capability
Key telephone system having wideband capability