scope:

This standard establishes the coding and modulation requirements for 4800 bit/second modems owned or leased by the Federal Government for use over analog transmission channels.

This standard is to facilitate interoperability between telecommunication facilities and systems of the Federal Government.

All Federal departments and agencies shall comply with this standard in the design and procurement of 4800 bit/second modems (and equipment containing modems) for use with nominal 4 KHz analog channels. Typically, nominal 4 KHz analog channels are derived from frequency division multiplex equipment associated with microwave, coaxial cable, and satellite transmission systems. Modems described by this standard may also be used on nonmultiplexed transmission systems such as metallic cable facilities.