摘要 |
A system for alternately transmitting an audio signal and a video signal over a single voice grade telephone line is disclosed. The system includes an apparatus located at a subscriber location which establishes a first communication connection between a user at the subscriber location and a dispatcher at a dispatch station, over which first communication connection transmission of voice signals are enabled to be simultaneously transmitted between the subscriber's premise and the dispatcher, and which disestablishes the first communication connection and establishes a second communication connection over which a continuous video signal is transmitted from the subscriber location to the dispatcher.
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