Telephone security system
Telephone system and method for reliable emergency services...
Telephone with built-in emergency panic switch, long distance to
Telephone-controlled electrical switch
Tone-responsive circuit for activating an instrumentality interf
Transaction safety system for falsely indicating successful comp
Two-way voice and voice over IP receivers for alarm systems
United home security system
Universal emergency number ELIN based on network address ranges
Universal line status monitoring and response system
Variable configuration portable telephone
Visual communication system and its main apparatus
Wireless phone-interface device