Figure 3-25. Baseband Loopback; Figure 3-26. Interface Loopback - Comtech EF Data SDM-300A Installation And Operation Manual

SDM-300A Satellite Modem
C USTO ME R
D ATA
R E M O T E S E R IA L
IN T E R FA C E
FA U LT IN D IC ATO R S
SATE LLITE M O D E M
Note: When baseband loopback is turned on, data is looped back on the customer side of the interface. This is a bi-directional loopback of the
baseband data. This test mode will verify the customer equipment and cabling between the modem and the customer equipment. The baseband
loopback is not bi-directional in D&I.
C US TO MER
DATA
R E M O TE S E R IA L
IN T E R FA C E
FA U LT IN D IC ATO R S
S AT E LLITE M OD E M
Note: When interface loopback is turned on, data is looped back on the modem side of the interface. This is a bi-directional loopback of the data
after the baseband data had the 16/15 overhead added. This test mode will verify the internal channel unit interface operation.
Rev. 4
IB S O R IDR
E NCO DE R/
M O DULATO R
IN TERFA CE
M ICR O -
CO M P UT ER
DE MO DU LATO R /
DE COD ER

Figure 3-25. Baseband Loopback

IBS or ID R
EN CO D ER /
M O DUL ATO R
INT ERFACE
MIC RO -
CO M P UTE R
DE MO D ULATO R /
DE COD ER

Figure 3-26. Interface Loopback

TRAN SM IT RF
EQ U IPME NT
PO W ER S UP PLY A C P O W E R
RE CEIVE R F
EQU IP ME NT
TRAN SM IT R F
EQ UIPME NT
A C P O W E R
P O W ER S UPP LY
RE CE IVE RF
E QUIPM EN T
Operation
A NT EN N A
A N TEN NA
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