Comtech EF Data SDM-300L3 - Manual (Page 99)

SDM-300L3 Satellite Modem Revision 1
Front Panel Operation MN/SDM300L3.IOM
4–31
FUNCTION SELECT: CONFIGURATION: INTERFACE:
INTRFC LOOP BACK (CONDITIONAL)
INTRFC LOOP BACK
OFF
IMPORTANT
This is a Test Mode. Conditional: This menu is only available when the
overhead interface PCB or Reed-Solomon PCB is installed.
Programs the modem for Interface Loopback operation. When INTERFACE
LOOPBACK is turned on, data is looped back at the modem side of the interface. This is
a bi-directional loop back of the data after the base band data has had the overhead added.
Refer to Figure 4-7 for the interface loopback block diagram.
Upon entry, the current status is displayed. [
↑ ] or [ ↓ ] to make the selection. Press
[ENTER] to execute the change.
CUSTOMER
DATA
IBS or IDR
INTERFACE
ENCODER/
MODULATOR
TRANSMIT RF
EQUIPMENT
ANTENNA
AC POWER POWER SUPPLY
MICRO-
COMPUTER
REMOTE SERIAL
INTERFACE
FAULT INDICATORS
RECEIVE RF
EQUIPMENT DEMODULATOR/
DECODER
SATELLITE MODEM
Figure 4-7. Interface Loopback
Note: When interface loopback is turned on, data is looped back on the modem side of the interface. This test mode will verify the
internal channel unit interface operation.