Zero the Traversing and Elevation Mechanism (T&E Mechanism)
Zero the T&E mechanism by zeroing the traversing handwheel, elevating handwheel, and the elevating mechanism sleeve to the lower elevating screw.
To zero the traversing handwheel:
- Hold the T&E mechanism so that the traversing handwheel is on the left when looking at it, then turn the traversing handwheel toward you until it stops.
- Loosen the locking nut slightly.
- Align the zero on the scale with the zero on the elevating screw yoke.
- Hold the scale with the zeros aligned, and tighten the locking nut. Make sure the zeros stay aligned.
- Turn the traversing handwheel two complete revolutions away from you. If doing this at night, count 50 "clicks" away from you.
- Align the two zeros.
- Rotate the elevating handwheel up or down until a zero with a line below it is visible on the upper elevating screw.
- Position the elevating handwheel so the indicator is pointing at the zero on the handwheel.
- Rotate the elevating mechanism sleeve all the way up; rotate it down until it stops and note the number of complete turns.
- Rotate the elevating mechanism sleeve up half that number of turns.
- Position the slide lock lever to face you.