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©2011 Johnson Level & Tool
• Turn the instrument 180º.
• If the target remains at the center of the reticle, no adjustment is
required. Otherwise, adjust as follows.
Calibrating
• Turn counterclockwise and remove the black
ring/adjusting screw cover located between
the optical eyepiece and the focusing knob.
• Place a sheet of paper under the instrument
and mark the optical plummet center mark
each time the instrument turns 90º, as shown in the figure:
point A, B, C, D.
• Line up points AC and BD to get the point of their intersection O.
• Adjust the four adjusting screws on the optical eyepiece with the
adjusting pin to align the center mark with point O.
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