Furuno FELCOM251, Installation Manual

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APPENDIX 1 GLOSSARY
AP-2
P
R
S
T
PAST Person Activated Self Test. A test similar to the POST test, but activated by the
user. The PAST causes the system to reset.
PIN Personal Identification Number. A secret numeric password shared between a
user and a system, used to authenticate the user to the system.
PoE Power over Ethernet. A standard for combining power supply with transmission of
data over the Ethernet. The source unit "injects" power into the Ethernet cable and
the power is "picked up" at the connected device.
POST Power On Self Test. A test sequence that runs every time the system is powered
up or reset.
RF Radio Frequency. Electromagnetic wave frequencies between about 3 kilohertz
and about 300 gigahertz including the frequencies used for communications sig-
nals (radio, television, cell-phone and satellite transmissions) or radar signals.
RFI Radio Frequency Interference. A non-desired radio signal which creates noise or
dropouts in the wireless system or noise in a sound system.
SIM Subscriber Identity Module.The SIM provides secure storing of the key identifying
a mobile phone service subscriber but also subscription information, preferences
and storage of text messages.
SSB Single Side Band. A means of communications at sea. The range of SSB is up to
several thousand miles and calls between yachts are free. Some stations allow
telephone calls, email and some basic Internet services over SSB radio.
TNC Threaded Neill-Concelman. A type of RF connector used for terminating coaxial
cables. The TNC connector is a threaded version of the BNC connector. The con-
nector has a 50 Ohm impedance and operates best in the 0-11 GHz frequen-
cyspectrum.