Statsionar—Russia's geostationary system for satellite telecommunications.
submarine cable—a cable designed for service under water.
TAT—Trans-Atlantic Telephone; any of a number of high- capacity submarine coaxial telephone cables linking Europe with North America.
telefax—facsimile service between subscriber stations via the public switched telephone network or the international Datel network.
telegraph—a telecommunications system designed for unmodulated electric impulse transmission.
telex—a communication service involving teletypewriters connected by wire through automatic exchanges.
tropospheric scatter—a form of microwave radio transmission in which the troposphere is used to scatter and reflect a fraction of the incident radio waves back to earth; powerful, highly directional antennas are used to transmit and receive the microwave signals; reliable over-the-horizon communications are realized for distances up to 600 miles in a single hop; additional hops can extend the range of this system for very long distances.
trunk network—a network of switching centers, connected by multichannel trunk lines.
UHF— ultra-high-frequency; any radio frequency in the 300- to 3,000-MHz range.
VHF—very-high-frequency; any radio frequency in the 30- to 300-MHz range.