ne
satellite that provides long distance transmission of voice,
data, and television; the system usually serves as a trunk
connection between telephone exchanges; if the earth
stations are in the same country, it is a domestic system.

satellite earth station--a communications facility with a
microwave radio transmitting and receiving antenna and
required receiving and transmitting equipment for
communicating with satellites.

satellite link--a radio connection between a satellite and an
earth station permitting communication between them, either
one-way (down link from satellite to earth
station--television receive-only transmission) or two-way
(telephone channels).

SHF--super-high-frequency; any radio frequency in the 3,000-
to 30,000-MHz range.

shortwave--radio frequencies (from 1.605 to 30 MHz) that fall
above the commercial broadcast band and are used for
communication over long distances.

Solidaridad--geosynchronous satellites in Mexico's system of
international telecommunications in the Western Hemisphere.

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.

Telephones: This entry gives the total number of
subscribers.

Television--broadcast stations: This entr