Hughes AN6-098P, Installation Manual

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Chapter 4 • Installing a J-type radio assembly
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1037312-0001 Revision B
5. Install the vertical shim and O-ring in the same location.
Because of its shape and alignment pins on the
transmit/receive isolation assembly (TRIA), the vertical shim
can only be installed in the position shown in Figure 24
(upper right photo). Note the position of the alignment pins.
Likewise, the horizontal shim can only be installed in one
position.
Because of the shim’s alignment pins, you must rotate the
TRIA 90 ° from its horizontal polarization position. You must
rotate the TRIA before you re-attach the waveguide end so
you can insert the shim alignment pins into the waveguide
end plate. See Figures 25 and 26.
Figure 26 shows how the TRIA is positioned for horizontal
transmit polarization compared to how it is positioned for
vertical transmit polarization.
Figure 25: Direction of TRIA rotation for vertical polarization