G.703/async interface, 4 g.703/async interface – Comtech EF Data SDM-300A User Manual
Page 90
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SDM-300A Satellite Modem
Revision 6
External Connections
MN/SDM300A.IOM
4–12
4.1.4
G.703/ASYNC Interface
The G.703 T1, E1/ASYNC Interface Adapter has three BNC connectors and a 15-pin
subminiature D connector.
• BNC connectors SD (J2) and RD (J3) support the G.703 unbalanced 75Ω TX and RX
data interfaces.
• BNC connector MC (J4) supports the 75Ω unbalanced Master Clock interface.
The 15-pin D connector (J5) supports the G.703 balanced TX and RX data, balanced Master
Clock, Open Collector MOD and DEMOD fault, and asynchronous overhead data interfaces.
Table 4-8 shows the pinouts for the 15-pin D connector.
This interface does not support access to IBS or IDR overhead signals and does not support
D&I.
Table 4-8. G.703/ASYNC Pin Assignments
Pin #
Signal
1
9
SD-
SD+
2
4
GND
3
11
RD-
RD+
5
12
ETXB
ETXA
6
13
ERXB
ERXA
7
8
MC-
MC+
10 N.C.
14 MODFLT
15 DMDFLT