Raymarine STV Gen2 Installation And Operation Manual page 16

You can connect two IRDs to your antenna as shown in the diagram.
In this system, one IRD can be set as a two satellite receiver. The
other IRD must be set as a one satellite receiver.
The RF connection into the IRD is usually made into the connector
labelled LNB, ANT, or Satellite In.
Refer to the relevant Manufacturer's handbook for details on
configuring your IRD.
System with 4 IRDs
You can connect four IRDs to your antenna as shown in the
following diagram.
20
RF cable
ACU
MADE IN KOREA
ANT RF1
- +
+ -
DC 9 to 30V FUSE NMEA
Power in
The RF cables from the antenna base plate connect to either the
LNB, ANT, or Satellite In connector on the rear of the IRD.
Refer to the relevant Manufacturer's handbook for details on
configuring your IRDs.
Antenna base plate
RF 2
RF 1
RF 3 RF 4
IRD1 (not supplied)
IRD2 (not supplied)
IRD3 (not supplied)
IRD4 (not supplied)
RECEIVER
PC INTERF ACE
STV Gen2 installation and operation