Specifications

Chapter 2 - Installation
42S315F 2-13
10. Hoist the spar and subreflector assembly into the reflector and align the
lower end of each spar with the attachment tab on a spar truss. Attach the
spars to the truss tabs as shown in drawing 517577 sheet 2, using four screws
(item 25), eight washers (item 27), and four nuts (item 26).
11. Torque all the fasteners used in the assembly and installation of the spars
and subreflector to the values corresponding to the correct sizes as indicated
on page 2-7.
2.4.6.3 Truss Alignment
Refer to drawing 517577C, 9-Meter Reflector Assembly, for the following
procedure.
1. Install the theodolite mounting bracket onto the panel mounting ring in the
hub using three 3/8 inch screws. It will only mount one way due to the
dowel pins.
2. Install the theodolite onto the mounting bracket. Level the theodolite over its
three feet using an 18-inch machine scale, measuring 16.850 inches [42.799
cm] up from the panel mounting ring. (See
Figure 2-1.)
3. Zero the azimuth scale of the theodolite while looking at the center of the
mounting bolt of the first truss to the hub.
4. Set the theodolite elevation angle to 80°-19'-38". Focus on the 1/4" diameter
gage hole in the top of the end plate on the truss. Adjust the truss laterally
and vertically so that the gage hole is centered on the theodolite telescope
crosshairs. Tighten the mounting screws for the truss at the hub, and the
screws which attach the outer diagonal braces to the truss.
NOTE
The truss tip elevation may be as much as 0°10' lower than
the above setting, but should not be any higher.
5. Set the azimuth angle of the next truss at 15° clockwise from the previous
truss. Set the elevation angle the same. Tighten the truss mounting screws
and the intercostals between the two trusses. Also tighten the inner diagonal
brace. Verify that the first truss remains as previously set.
6. Set the remaining trusses as in step 5. Only the first truss and its two
adjacent trusses have diagonal braces attached to them.
7. Assure that all truss and intercostal fasteners are torqued as specified in
Table 2-2 on page 2-7.
2.4.6.4 Installation of Reflector Panels
Refer to drawing 517577, 9-Meter Reflector Assembly, for the following
procedure.