TM 5-6675-329-13 & P
Table 3-1. Troubleshooting
TEST OR INSPECTION
CIRCULAR LEVEL (8, FIGURE 1-2) BUBBLE DOES NOT REMAIN CENTERED WHEN INSTRUMENT IS
ROTATED THROUGH 360°
Check that footscrews (2, Figure 1-2) have not moved.
Check that Tripod Assembly GST-40 leg (s) (4, Figure 1-3) has not moved.
Readjust footscrews to center bubble at Automatic Level position (s) where it
goes off center. Re-rotate Automatic Level NA2 through 360° If bubble still
goes off center, this indicates that footscrews have not moved, and circular level
requires readjustment. Refer to Maintenance Section III.
There should be no play between the various components of the Tripod
Assembly GST-40. The hexagonal key kept in the tripod pouch should be used
to tighten up the tripod screws when necessary. The hinges between the tripod
head and the legs can be adjusted; they should be sufficiently stiff so that when
the tripod is lifted by its head the legs just remain spreadout.
LINE OF SIGHT DOES NOT REMAIN HORIZONTAL.
Check that circular level (8, Figure 1-2) bubble is centered.
Press test pushbutton (7, Figure 1-2) and observe image movement in eyepiece (6).
The circular bubble is in correct adjustment when it stays in the center of the
circle in whatever