Harris Constellation, Installation & Maintenance

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Constellation™ November 2003
Glossary-4
NEC
National Electric Code (registered trademark of the National Fire
Protection Association).
Noise Figure
The ratio of the output noise power to the portion of the
output noise power stemming from thermal noise at the input at standard noise
temperature.
NP
NonProtected.
O
OCXO
Ovenized (proportional Control) Crystal Oscillator.
OEM
Original Equipment Manufacturer.
P
PDU
Protocol Data Unit.
PLL
Phase-Locked Loop.
Q
QUICC
QUad Integrated Communications Controller.
R
RCS
Reverse Channel Switch.
RF
Radio Frequency.
RIP
Routing for Internet Protocol.
RMA
Return Material Authorization.
RMS
Rack-Mounting Space.
RSL
Received Signal Level.
RX
Receiver.
S
SCAN
System Control And Alarm Network. Harris’ proprietary standard for
sending alarm/status/control messages over a serial port.
SD
Space Diversity. Pertaining to signal transmission and reception in which
two or more separate and independent propagation media or paths are used for
transmitting the same information.
SES
Severely Errored-Seconds.