were performed with the use of an in-house "3-dimensional frame" computer program. The resulting deflections curve and slopes are shown in Fig. 3.3-38 and 3.3-39 for the primary structure. To evaluate the effects of secondary structural deflection on the overall deflection, a section of structure farthese from the antenna center was chosen for examination. This particular area was chosen because (1) it is the area that the primary structure experiences its largest deflection and (2) the temperature gradients are highest. Figure 3.3-40 reflects the deflections and slopes calculated for the secondary structure, and as can be seen, the magnitudes will contribute very little to the overall deflections. Note that Fig. 3.3-38 and 3.3-39 show the deflections and slopes calculated for temperature deviations that occur during different seasonal and orbital positions. The mean curves represent the location and angle that the respective waveguide arrays would be assembled to the secondary structure. The waveguide assemblies within approximately the 16,000 in. (406 M) radius can be preset or "timed" once and left alone. Those located beyond this radius must be adjustable in flight by use of screw jacks or similar devices. Further elimination of adjustable devices can be achieved by judicious design procedures to reduce deflections at the antenna periphery. Close manufacturing tolerances will have to be augmented by an adjustment or "tuning" technique in order to minimize built-in waviness and deflections. A study of tolerances, both manufacturing and assembly would determine the extent and type of adjustment that would be necessary. A typical girder 18 meters long has the following tolerances:
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