SGC SG-2020 TEST DOCUMENT, Installation And Operation Manual

Page: 77 / 95

73
© 1998 SGC Inc
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA. 98005 USA
P.O.Box 3526, 98009 Fax: 425-746-6384 or 746-7173 Tel: 425- 746-6310 or 1-800-259 7331
E-mail: sgc@sgcworld.com Web site: http://www.sgcworld.com
CARRIER: An unmodulated RF signal.
CHAN: Channel.
CHASSIS GND: Chassis or cabinet ground.
CLAR: Clarifier; allows receiver frequency to be offset slightly from
transmitter frequency.
COMM: Communication; also used to reference serial communications
computer port.
CW: Continuous wave; to transmit the mode of Morse code.
CRYSTAL: A piece of quartz mineral that will resonate at a particular
frequency and used as a reference in transceivers.
COAX: An electrical conductor which carries radio energy from a transmitter
to an antenna system; the inner conductor is insulated from an external
wire mesh shield.
CHIP: A wafer of semiconductor material used in an electronic circuit.
COPY:When radio operators hear and write down a message, they "copy."
DATA I/O: Data input/output.
DC:
Direct current.
DUPLEX: A method in which ship stations transmit on one frequency while
shore stations transmit a different frequency
DSP: Digital signal processing; technology which eliminates unwanted
noise to enhances a signal.
DXpedition: A contest in which amateur radio operators try to reach distant
stations.
EMER: Emergency.
FEC: Forward error correction; a mode to compare transmission; each
character is sent twice and the redundancy of the code serves as the
check.
FEEDLINE: The method of connecting the antenna to the radio.
FREQUENCY: The number of polarity alternations per second measured in
Hertz. KHz=thousand Hertz; MHz = million Hz.
FM: Frequency modulation.
FWD: Forward transmit power going to the antenna.
GAIN: The amount of amplification a system has; in antenna systems, the
gain is the measurement of the directional characteristics.
GROUND: A connection to earth or an earth counterpoise.
GROUNDPLANE: An artificial ground used for antenna systems.
GROUNDWAVE: A radio signal that travels along the earth, bending over
the horizon.
GMT: Greenwich Mean Time (universal time) the international standard time
referred to the zero degree meridian.
HETERODYNE: The frequency that results when two radio frequencies
"beat" together (one frequency minus the second frequency =
heterodyne).
HERTZ: See Hz.