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Can Anyone provide me a manual for Sokkia FX 101 1"... any help will be helpful
You can do a topographic survey with a total station using a method called trigonmetric leveling. There are several ways of doing it depending on your hardware and software combinations you are utilizing. Here is a basic outline.
Information needed.
1) Reference datum (some known benchmark you wish to relate your topographic survey to). You can assume a starting elevation if you wish.
2) Height of instrument (this is measured from the top of the mark your total station is set up on to the line or hole that is on the same plane as the scope). You can adjust this measurement for a true instrument height if you wish, although this is typically not necessary.
3) Height of prism (this is measured from bottom of pole to center of prism). = HP
What you record for each observation.
1) Zenith angle, slope distance and horizontal angle. (Most modern total stations contain a function where you can ask it to display the prism difference "PD" instead of the slope distance and Zenith angle and you can record that instead but you need the slope or horizontal distance to locate your point horizontally relative to your total stations location.)
How you determine elevations. (I recommend that you always run a conventional control elevation loop through your control points using a level but there are several methods for performing the necessary double checks to assure your results).
1) Set your total station up over a known control point (you know the elevation of it) and backsite a known control point (you know the elevation of it also). This is done so you can check to make sure you have done everything right BEFORE you start making observations.
2) Add the height of instrument (HI) to the elevation of the control point you are setup on. (BM elevation + HI = Elevation of instrument or EI).
3) Make an observation on your backsite point. The Slope distance times the sine of the Zenith angle gives you the prism difference or (PD). The PD is subtracted (or added, depending on the result) from your EI. You then substract the HP to obtain the elevation of the point you located.
Thanks for your immense reply ... it helped me a lot ... sorry for my late thanks....
Hi Deward!
Taking time to reply with that length and details, I can tell you're a real surveyor at heart..
Have a pleasant afternoon from the Philippines.
Regards,
Arnel
YES! You two guys should definitely meet. I must say that you two are by far two of the most dedicated and passionate surveyors that I know from your respective areas of the world, if not the entire world. Thank you both for continuing to help other members in need! This is what it is all about!