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Gemini
PD
Installation Guide
Definitions
The following terms are used throughout this document.
Item
Definition
DCE
Data Communications Equipment. This designation defines the direction (input
or output) of the various RS-232 interface signals. Modems are always wired as
DCE.
DTE
Data Terminal Equipment. This designation defines the direction (input or out-
put) of the various RS-232 interface signals. Most user equipment, as well as
PCs, are wired as DTE.
GCU
Gemini
PD
Control Unit board
Gemini
PD
High specs mobile radiomodem. PD = Parallel decode
HDX
Half Duplex. A unit that uses separate transmit and receive frequencies, but
which may not transmit and receive simultaneously.
RS-232
Industry–standard interface for data transfer.
RIS
Radio Installation Software. This software allows basic tests and unit configura-
tion.
Simplex
A unit which uses the same frequency for transmit and receive.
