Comtech EF Data SDM-2020 - Manual (Page 187)

SDM-2020 Satellite Demodulator Revision 4
SMPTE-310M Data Interface MN/SDM2020D.IOM
12–5
Environmental
Operating Temperature
Storage Temperature
Humidity
0 to + 50 °C (32 to + 122°F)
-40 to + 70 °C (-40 to +158°F)
Up to 95% non-condensing.
Physical
Size
SDM-2020 plug-in module compatible.
Hot Pluggable Not required. Unit power is turned off prior to removal or insertion of
the data interface.
12.1.3.2 Interface Loopback Mode
In loopback mode, data entering the TX connector is returned to the RX output connector
after passing through the interface. The data entering the interface at the TX input is
routed all the way through the TX path and out to the modulator at J1. All TX signals
going to the modulator are routed back to the RX path in place of the normal signals,
which would be coming from the demodulator.
• In a Modulator, TX data continues to enter the modulator and is TX during
loopback.
• In a Demodulator, satellite data is not routed through the SMPTE-310M Data
Interface.
12.1.3.3 Interface Loop-Through Mode
In loop-through mode (Modulator Only), operation is the same as in loopback mode,
however, the test mode LED indications are not activated.