Glossary - Geodesic Sensor Net Technical Manual

G
LOSSARY
A
Ag/AgCl See silver/silver chloride .
amp/amperage A measure of the
amount of current, or number of
electrons, moving across a point.
amplifier A circuit that increases the
voltage, current, or power of a signal.
artifact An inaccurate observation,
effect, or result, especially one resulting
from the technology used in scientific
investigation or from experimental error.
C
cable A group of two or more insulated
wires.
channel Each sensor of the Geodesic
Sensor Net is cabled into the amplifier
where its signal is converted into a
stream of digital values. Each of these
streams is the data of a channel.
CMR See common mode rejection .
common An electrical point that
functions in much the same way that an
Geodesic Sensor Net Technical Manual
S-MAN-200-GSNR-001 • January 31, 2007
earth ground does, but is separated from
earth ground by an isolation barrier
(typically thousands of volts of
isolation) in the interest of safety.
common mode rejection A measure of
the attenuation of noise induced in the
signal or reference lines relative to
common. The ratio is typically
expressed in decibels .
conductivity A measure of the
tendency of a material to transmit
electrons; the reciprocal of impedance .
connector Any plug and socket that
links two devices together.
contact Current carrying part of a
switch, relay or connector.
current Measured in amperes, this is
the flow of electrons through a
conductor. Also know as electron flow.
D
dB See decibel .
decibel A logarithmic measure of the
ratio between two values. For electrical
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