Hilger Watts Theodolite Manual 〈Recommended ●〉

Use the foot screws and the plate level to bring the bubble to the center. Final Centering: Use the optical plummet to center exactly.

Read both the horizontal and vertical circles using the optical reading system and record your angles in your field book.

A coincidence reading system is used where double lines must be perfectly aligned using the micrometer knob before reading the exact seconds. 4. Maintenance, Calibration, and Troubleshooting hilger watts theodolite manual

Turn the main internal focusing knob until the target is clear. Move your eye slightly up and down; if the crosshairs appear to shift against the target, eliminate this parallax error by fine-tuning the focusing knob.

Use the horizontal and vertical tangent screws to bring the center crosshair onto the precise point of your target. Step 4: Reading the Glass Circles Use the foot screws and the plate level

: You’d plant the heavy wooden tripod, adjusting the legs until the "bulls-eye" level showed a perfect, centered circle.

Sight a sharp target at Face Left, record the reading. Flip to Face Right, sight the same target. The difference should be exactly 180 degrees. If an error persists, use the reticle adjusting screws to shift the crosshairs halfway toward the correct reading. Care and Storage A coincidence reading system is used where double

Proper setup is crucial for accuracy. The manual emphasizes the following steps:

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