Comtech EF Data DMD2401/DMD2401L - Manual (Page 36)

DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem Operation
TM065 - Rev. 3.3 3-13
For the Receive Side:
1.
With Rx Side Channels configured as follows: CH1 to TS1, CH2 to TS2, CH3 to TS3 and
CH4 to TS4.
2.
After the timeslots are assigned properly, scroll to the Mapping Menu and use the above
procedure to enter the settings into the modem.
3.
Set the display to read:
Map Copy
RX EDIT > RX ACTIVE
4.
Press to enter the settings into the modem.
To View the current Timeslot Assignment:
1.
If there is a question of the channels not being entered properly, the Mapping Menu may
be used to see how the channels/timeslots are configured in the modem.
2.
Use and the Arrow Keys to make the mapping menu read (for the Tx Side):
Map Copy
TX ACTIVE > TX EDIT
3.
Press . The modem has now copied the current Tx Settings to the Tx
Channel/Timeslot Display.
4.
For the Rx Side:
Map Copy
RX ACTIVE > RX EDIT
5.
Press . The modem has now copied the current Rx Settings to the Rx
Channel/Timeslot display ).
Note: It is not mandatory to assign timeslots in sequential order, although the lowest
timeslot must be entered in the lowest channel. For example: timeslots may be assigned
1-2, 2-5, etc. but not 1-5, 2-2.
3.12 Loopbacks
3.12.1 Terrestrial Loopback
Terrestrial Loopbacks provides the following data loopback on the interface card:
Tx Loopback – Terrestrial TX data after passing through the line interface is looped back
to the Rx data line drivers (refer to Figure 3-3).
Rx Loopback – The Rx data received by the satellite is looped back through the interface
for retransmission to the satellite providing a far end loopback (refer to Figure 3-4).
Tx/Rx Loopback – Provides both of the above loopbacks simultaneously (refer to
Figure 3-5).