TM 5-6675-330-12&P
(a] Lay out three points in a straight line, These
points do not have to be on a level plane, but they
should be on a uniform grade, The intermediate
point should not divide the line into two equal
segments.
Figure 9- System Offset Correction Test Layout
(b) Set the offset (5) ppm (13) switches on the front
panel to 00.
[c) Set up the instrument on each of the three
points and make measurements to each of the
other points. This gives double measurements for
both segments of the line and for the overall
length; that is, one measurement will be made
from each end of each line, Use the mean of the
two measurements in the calculation. All
measurements consist of the mean of ten
individual range displays on the instrument.
[d) Compute the total offset correction, using the
designations in figure 9 and the following
equations,
C = A + B
MA = Mean distance read for Segment A
MB = Mean distance read for Segment B
MC = Mean distance read for Segment C
Then:
TOC = MC –(MA+MB]
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