Caller ID system with retransmitted caller ID information

Caller ID telephone with signal attenuation

Calling system for short duration data transactions

Carbon microphone interface for a modem

Carrier locating system

Cash access system and method of operation

Cellular mobile radio credit card system

Cellular mobile radiotelephone-based system for rental of mobile

Cellular telephone for acquiring data encoded in bar code...

Central monitoring station with method to process call based...

Centralized management unit receiving data from management...

Certified telephonic transmissions

Change-over system for automatic answering telephony and facsimi

Character pattern recognition and communications apparatus

Charge code entry in preprogrammed dialing

Check for pending e-mail using caller ID and selective...

Check for pending e-mail using caller ID and selective...

Circuit arrangement for integration of EDP systems in the utiliz

Circuit breaker remote service system

Circuit connecting a voice-controlled device to a telephone stat