B-band loop back off, Figure 4-6. baseband loopback – Comtech EF Data SNM-1001L User Manual
Page 93
SNM-1001L Satellite Modem
Revision 1
Front Panel Operation
MN/SNM1001L.IOM
4–29
FUNCTION SELECT: CONFIGURATION: INTERFACE:
B-BAND LOOP BACK
B-BAND LOOP BACK
OFF
IMPORTANT
This is a Test Mode.
Programs the modem for baseband loopback operation. When baseband loopback is turned on,
the data and timing signals are switched from the demodulator to the modulator on the modem
side of the interface. The DTE baseband signals are also looped back from the transmitter data
and clock to receiver data and clock on the customer side of the interface. This is a bi-directional
loopback of the baseband data. Refer to Figure 4-6 for a block diagram of baseband loopback
operation.
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Figure 4-6. Baseband Loopback
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.