Electronic audio communication system with user controlled...
Electronic audio signalling device for telephones
Electronic audio signalling device for telephones
Electronic audiocommunication system
Electronic battery feed circuit for telephone systems
Electronic bridge circuit for supplying dc power and tone...
Electronic business telephone
Electronic business telephone
Electronic call assistant
Electronic cancellation of ambient noise in telephone receivers
Electronic circuit for detecting the lifting of a telephone...
Electronic common switch
Electronic communication and switching system for...
Electronic communication message system
Electronic communications manager
Electronic communications system and method
Electronic current feed circuit
Electronic device for connecting a subscriber line
Electronic device having internal charge regulator for...
Electronic device with extendable keyboard