The Optical Plummet; Setting The Vertical Zero Position - David White DWT-10 Instruction Manual

3. Optical Plummet
This adjustment is required to make the line
of sight of the optical plummet coincide with
the vertical axis.
A) Point the optical plummet at a ground target. This can be done by adjusting the
level screws or by loosening the instrument fastening screw and moving the instru-
ment over the target.
B) Turn the instrument 180° (200g) around and re-sight
the target through the optical plummet. If the target is
still centered, no adjustment is necessary. If not, go to
step C.
C) Remove the adjusting screw cover from the
optical plummet. Unscrew in a counterclockwise
direction. This will expose four reticle adjusting screws.
D) Using the adjusting pin provided in the case,
turn the reticle adjusting screws until half the
displacement has been removed. Loosen
one screw 1/4 turn, then tighten the
opposing screw 1/4 turn.
E) Repeat steps A through D until there
is no displacement of the target when
the instrument is turned about its vertical
axis
5.3 Setting The Vertical Zero Postion
PROCEDURE
Accurately level the instrument
Press and hold the V% key while pressing
the power key. The instrument display will
enter the vertical zero adjustment mode.
Turn the telescope past the zero point.
The display will show "STEP 1".
Sight the telescope at a target that is level
with the instrument within 10 seconds.
Press "V%". This will store the data for the
first point. The display will show "SHOW --2".
Reverse the telescope and re-sight the
original target. Press the "V%" key. This will
store the data for the second point and
establish a vertical zero point at level. Once a
key is pressed, the instrument will beep and
return to regular measurement mode.
KEY DISPLAY
N/A
V%
V
O S E
V
9 5 1 0 2 0
H
S E - - 1
R
V%
V
9 5 1 0 2 0
H
S E - - 2
R
V%
V 2 6 1 1 2 4 3
H
1 8 0 0 0 0 0
R
L
L
L
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