Abstract: A method and apparatus is disclosed which allows the sending or receiving of either speech or digital data calls over a phone line by correctly connecting either a digital data machine or a voice phone with the line without any human involvement. An analyzer connected to the phone line interrogates each incoming call to determine if it is a voice call or a digital data call. If it is a voice call, the analyzer rings the phone and connects it to the line when the phone is answered. If the incoming call is a digital data call, the data machine, e.g., fax, is connected to the phone line. The distinction between voice and digital data calls is based in part on analyses of incoming response to an interrogation of the caller with messages from a speech synthesizer. For outgoing calls, the analyzer determines which of the phone and the data machines becomes active, and connects the active one with the phone line while it blocks access to the line by the other one until the outgoing call is complete.