9-4

9 CHECK AND ADJUSTMENT
9.3 Checking/Adjustin g the Theodolite Functions
lPointers on the Adjustment
1) Adjust the eyepiece of the telescope properly prior to any checking operation which involves
sighting through the telescope.
Remember to focus properly, with parallax completely eliminated.
2) Carry out the adjustments in the order of item numbers, as the adjustments are dependent one
upon another. Adjustments carried out in the wrong sequence may even nullify previous
adjustment.
3) Always conclude adjustments by tightening t he adjustment screws securely (but do not ti ghten
them more than necessary, as you may strip the threads, twist off the screw or place undue stress
on the parts).
Furthermore, always tighten by revolving in the direction of tightening tension.
4) The attachment sc r ews must also be tightened suf fi ciently, upon completion of adjustments.
5) Always repeat checking operations after adjustments are made, in order to confirm results.
lNotes on the Tribrach
Note that the an gle measuring p r ecision may be effected dire c tly if the tribrach has not been inst alled
firmly.
1) If there is any slack between the leveling screws and the base, loosen the set screw of the holding
ring and tighten the holding ring with adjusting pin, until it is properly adjusted. Re-tighten the set
screw on completing the adjustment.
Leveling screw Holding ring Set screw