Intellian i2 Operation Manual page 19

Twin IRDs Connection
You can connect two IRDs for your antenna as shown in the following
diagram. One of the IRD's need to be set up with the ACU in order to use
another IRD without connecting the ACU. Both IRD's with and without an
ACU connection can receive any channels that are available from the
tracked satellite.
As in the single IRD option, the RF cables from the antenna base plate
should be connected to 'LNB', 'ANT', or 'Satellite In' on the rear panel of
the IRD.
RF1 RF2
RF Cable
Antenna
ACU
DC Power Cable NMEA GPS PC Cable
Figure 16 : Dual-IRDs Configuration
IRD2 (Not Supplied)
ACU IRD Cable
Receiver IRD1 (Not Supplied)
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