Electronic patching system for telecommunications devices
Electronote wall mounted messaging device
Exchange and conference communication method therefor
Extension ringing arrangement key telephone system
Extension-in-use exclusion apparatus
Feature telephone integration device
Format-converting device and private branch exchange system...
Graphical user interface workstation
Highway expansion apparatus for key telephone system and...
Hold detecting and control circuit for a key telephone system
Hold-off alert system
In-line telephone intercom system
Information communication systems
Information processing and communication apparatus
Integrated telephone and intercom system
Intercom system
Intercom system for a service establishment
Intercom telephone
Intercommunication system for telephones
ISDN dual bus extension phone system