Multiplex Distribution System for Multichannel Pager Phone Communications

摘要

The report covers the development and prototype installation of the multiplex distribution system, which gives private communications capability to simple pager phones at minimum cost. This was accomplished by adding an applique to conventional pager-type telephones to allow them to communicate and interact with a multiplex distribution unit that serves as a miniature private branch exchange. Through this mechanism, the pager phones are able to receive and generate private calls without the expense of a complete multiplex telephone unit at every location. A special commercial telephone interface unit was also developed that allows outsiders to call directly to any pager in the mine and allows mine personnel to call any 1 of 10 preset outside telephone numbers.