Topcon GTS-821A, GTS-822A, GTS-823A, GTS-825A, Instruction Manual

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9-4
9 CHECK AND ADJUSTMENT
9.3 Checking/Adjusting the Theodolite Functions
l Pointers 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 the adjustment screws securely (but do not tighten
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 screws must also be tightened sufficiently, upon completion of adjustments.
5) Always repeat checking operations after adjustments are made, in order to confirm results.
l Notes on the Tribrach
Note that the angle measuring precision may be effected directly if the tribrach has not been installed
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