18 Raymarine Satellite TV Systems
Multiple IRDs
IMPORTANT: Due to satellite polarization, incorrect connection in
systems using multiple IRDs will result in signal degradation. Make sure
you select the correct method of connection for your area of operation.

North American systems and South America (DirecTV)

In order to connect three or four IRDs to the antenna, you will need to
purchase an active multi-switch with 2 satellite ‘in’ ports (Raymarine
recommends the Channel Master 6314 IFD), and the necessary additional
RF cables.
The multi-switch has to be installed between the antenna unit and the IRDs
as shown in the following diagram.
When you use a multiswitch, the signal from the satellite receiver can no
longer tell the antenna when to automatically change satellites. In order to
change the satellite being tracked, you must use the ACU. For example, in
some areas DirecTV programming is found on DTV101 and DTV119 (local
channels) When tracking DTV101, all of the receivers can receive
programmes from that satellite. If you want to see programmes on
DTV119, you need to manually change the satellite being tracked by
pressing Satellite B on the ACU. This means that all receivers can then
watch the programmes available on DTV119.
To connect three or four IRDs:
1. Connect an RF cable to RF1 and another to RF2 on the antenna base
plate.
2. Connect the RF1 cable to LNB LHCP/+18 V on the multi-switch.
3. Connect the RF2 cable to LNB RHCP/+13 V on the multi-switch.
4. For each output required, connect an RF cable from an OUT connector
of the multi-switch to the LNB or ANT connector of the individual IRD
units.
5. Terminate any unused connections with a suitable 75 Ohm DC termi-
nator block.
6. Connect the multi-switch to the appropriate DC power supply.
RF1
RF2
POWER/
DATA
Multiswitch
LNB
RHCP/+13V
VHF/UHF
INPUT
POWER
24V DC
LNB
LHCP/ +18V
OUT 3OUT 2OUT 1 OUT 4
GROUND
Antenna
baseplate
IRD 1 IRD 2
IRD 3 IRD 4
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