Interface Loopback; Engineering Service Channel (Esc); Figure 5-8. Interface Loopback Block Diagram - Comtech EF Data SDM-9000 Installation And Operation Manual

SDM-9000 Satellite Modem

5.5.3.3.2 Interface Loopback

Interface loopback provides loopback at the interface between the interface module and
the modulator/demodulator. The near end equipment loops through the interface module
and the far end equipment loops through the modulator/demodulator. Refer to Figure 5-8
for a block diagram.
TX DATA/CLOCK
TERRESTRIAL
DATA/CLOCK
RX DATA/CLOCK

5.5.3.4 Engineering Service Channel (ESC)

The ESC includes the following features:
•
•
•
Rev.4
INTERFACE
MODULE

Figure 5-8. Interface Loopback Block Diagram

Two full duplex audio channels or one 64 kbit/s data channel
A full duplex 8 kbit/s data stream
Four backward alarms (described in IESS-308)
INTERFACE
MODULATOR
LOOPBACK
TX DATA
MUX
DEMODULATOR
RX DATA
Theory of Operation
DATA
TX IF OUT
MODULATOR
MODULE
DATA
DEMODULATOR RX IF IN
MODULE
5–27