Key telephone system intercom arrangement
Key telephone system interconnection apparatus
Key telephone system line circuit
Key telephone system provided with telephone sets...
Key telephone system signal priority arrangement
Key telephone system signalling and control arrangement
Key telephone system signalling and control arrangement
Key telephone system signalling and control arrangement
Key telephone system with enhanced connectivity
Key telephone system, key telephone, interface unit, and...
Key telephone unit protective coupler
Key-pad control arrangement
Keyboard and display terminal
Keyboard for a dialling device for telecommunication systems
Keyboard security for a telephone attendant console
Keyboard type telephone station adapted to transmit dialling...
Keyless and indicatorless local telephone switching system
Keyless portable cellular phone system having remote voice...
Keypad and method of manufacture
Keypad apparatus