Perpend Cularity Of Line Of Sight To Horizontal Axis; Vertical 0 Point Error - Pentax W-821NX Basic Instruction Manual

4.4 Perpendicularity of Line of sight to horizontal axis
[Checks]
Position a target Point A at a distance 30m - 50m away from the instrument, and sight it
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with the telescope.
Loosen the telescope lock screw and turn the telescope until a point is sighted at a dis
Ç
tance roughly equal to that of Point A. This is Point B.
With the telescope still reversed loosen the horizontal lock screw and rotate the
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instrument around the vertical axis, and sight Point A again.
Loosen the telescope lock screw and turn the telescope until a point is sighted at a
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distance equal to that of Point B. This is Point C.
No adjustment is necessary if Point B and C are aligned.
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[Adjustments]
If Points B and C are not aligned, mark Point D at 1/4 the length of the BC, from
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Point C in the direction of Point B.
Using the adjustment pin, rotate the reticle adjustment screws horizontally opposite
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each other (see preceding page), and move the reticle to sight Point D.
Repeat the check and make sure the adjustment is correct.
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* Since the W-822NX and W-823NX have triple axis compensation, it is necessary to make
other settings besides the adjustments mentioned above.
For details, contact the dealers from whom the instrument was purchased.

4.5 Vertical 0 point error

Be sure to follow check procedures mentioned below after making adjustments on reticle and
perpendicularity of line of sight to horizontal axis.
[Checks]
Set up the instrument and turn the power on.
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Sight the telescope at any reference target A at Normal state. Read the vertical angle ( ).
Ç
Turn the telescope and rotate the alidade. Sight the same target A again at Back state
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and read the vertical angle R.
If +R = 360°, no further adjustment is necessary.
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[Adjustments]
If the deviation d ( + R - 360° ) is wide, contact your local dealer.
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