Modem History Development
Before the smart modem, almost all modems need two steps to produce a connection: the first step, manually dialing each other's number on the phone, and then placing the handset in the acoustic coupler attached to the modem, a device consisting of two rubber cups used for converting between sound signals and electrical signals. Using smart modems no longer requires acoustic coupler, but directly connects modems to a standard phone line or socket. Then the computer can automatically complete the phone and dial the number of functions. This change greatly simplifies the installation and use of bulletin board systems (BBS).
The speed of the modem to the 1980 has not changed much. The United States generally uses a 2400 bit/s system similar to Bell 212, whereas Europe's systems differ somewhat. By the late 1980, most modems were able to support all the standards at that time and 2400bit/s gradually popularized. A large number of specific use standards are also added, usually using high-speed channels to accept low-speed channel transmission, the typical example is the French Minitel system, the user terminal for most of the time to receive information. Modems of the Minitel terminal use 1200BIT/S to accept the data 75 bit/s Send command feedback to the server.