So we get an opportunity to pick up a pair of used topcon hiper Ga base/rover reasonal. Have found these bullit proof with few issues before so seemed like no brainer. Set up with survey pro 4.1.1 and tried up to latest greatest survey pro on different data collectors trying to test it out.
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Keep getting vertical errors of about 0.30' on known projects when i pick the antenna height as "Hiper" or any variation of it. Horizontal is fine. Some are localized, some are state plane with geoid so its not control. Things check with other recievers on these consistently. Using 2m rods so not that simple. 2 dealers seemed stumped. Is it possible the antenna offset is somehow hard set in the receivers?
I can set them as a manual antenna with a zero offset and get the vertical to check, but it causes some connection issues at times. Just have heartburn not understanding the issue. Survey pro versions vary the phase center offsets from version to version but it is minor (hundredths) I assume from NGS precise antenna height updates.
I had another guy test also thinking Im busting a setting like rod height and same result. Even Reset recievers with TRU and configured to some standard specs we have from past. Im stumped. Anyone ever seen something like this? Thanks for any ideas
What geoid is in the data collector? have you made sure that your firmware is up to date, in both units?
Checked with geoids 99 (one project control started pre-2003), 09, and 12a on different projects so I generally ruled that out. I don't know where these have been so maybe firmware is the next step. I don't have a history on them, and hadn't thought about that. Thanks.
Could it be a setting for a phase center offset? I did a quick look at the NGS data for that model and there is an "up" number of 87mm which is roughly 0.3'. If I remember correctly there is also a difference between relative and absolute centers and there may be a setting for this as well.
Good luck and hope you find the answer!
If its TDS/Spectra Precision Survey Pro then it is a Phase Center offset problem. If you have someone around you using Carlson or another field software, configure the same way and test...more than likely you'll come out right. This is extremely common between various versions, unfortunately, no one has been able to provide me with answers.