I am setting a Bench Mark for an elevation certificate. I ran my TR-2 for four 2-1/2 hour sessions and summited the data to OPUS. I got elevations of
371.27', 371.80', 371.87', and 371.27'. This is a 0.60' spread. The most spread that I have gotten in the past was 0.20'. This much spread concerns me as I have been bragging that I can get within 0.10' on elevations.

My other question is should my position light be steady green or flashing green. Mine flashes about every 3 or 4 seconds. I have not timed it.

My TR-2 is back on the job for four more 2-1/2 hour sessions

Matt Johnson

Well-Known Member
How do I summit the files to DPOS from the TR-2?


Is the position light flashing correct?

What color was the position LED? It should normally be solid green. Are you it was flashing and not the Recording LED?

I think I figured out how to send the data to DPOS, but the report says, "No cors in range". I will confirm that the position light is flashing tonight.

It is great that I can get help.
I did four more 2-1/2 hour sessions. The OPUS spread was 0.29'. The DPOS spread was 0.15'. 371.64', 371.68', 371.78', and 371.79'. I think I have a good elevation. I have learned a lot. Thanks to all who helped. The support is amazing.

Nate The Surveyor

Well-Known Member
Charles, I did alot of L1 work, yrs ago. The reason and logic behind @Shawn Billings accuracy diagram is related to the rotation of the earth, the rotation of the satellites, relative to earth, and the combining of data from a whole pass, (satellites pass over the earth) and parts of data from all available Satelites, during a 4-6 HR session, vs only a 2.5 HR session. I've been using DPOS now for some 5 yrs. A long DPOS session is fundamentally going to yield higher accuracy, than a short one. Due to a larger sample, for a statistical measurement system.
Keep learning!
Combining and averaging several 2.5 HR sessions will accomplish a similar thing, but I lean towards sessions that are 6 hrs, (1/4 rotation of the earth) long. And, knowing when the better satellite geometry is available. Ie, mission planning.