direct-coupled modem - a multi-standard alternative to the acoustically-coupled modem

direct-coupled modem elektor october 1984 direct coupled modem a multi-standard alternative to the acoustically- coupled modem A kit of the "problem" parts for this modem will be available from Technomatic Ltd. Please contact them directly for details. Type approval Quite understandably British Telecom want to be sure that any equipment connected to the telephone network meets a certain standard. For this reason modems, like other telecommunications equipment, must be submitted to the British Approval Board for Telecommunications before being connected to the telephone lines. At the moment the process of type approval is neither fast nor inexpensive but what will happen when BT is made private is anybody"s guess. In preparation for this project we pub- lished an article in last month"s issue ("data transmission by telephone") to deal with the theory behind the connection of a modem to the telephone network. That article also dealt briefly with the AM7910 modem IC that is used in t...