Big issue with data repeatability - position error over 10cm

Hi everyone, thank you for your reply.

I’ve already done the field test emlid’s support asked me, and maybe the problem could be the NTRIP provider. I have the subscription with TOPCON NTRIP Service, and as you can see from the data, that points have problem, the TPOS NTRIP (local ntrip provider) points doesn’t.

Emlid support requested me a 15 minutes observation with TOPCON NTRIP, then 4 survey: 2 with TOPCON and 2 with TPOS, after every survey I’ve done a complete reboot of the device.

I’ve collected 10 points per survey, point name is: “NTRIP USED”-RTK-“SURVEY NUMBER”-“POINT NUMBER”

Here you can download all the data:

https://drive.google.com/drive/folders/1Ck8n9v1P5ozeeS2RYvJOamkSBEsELwOP?usp=sharing

inside you can find:

  • Test emlid support (raw CSV file from flow project)

  • data_alldata_excel (same as csv but imported in excel)

  • Data_dividedPer-NTRIP-network (excel divided per survey, and divided by ntrip used. Then the table with elevation divided per survey)

  • Logs from all things done, except per TPOS survey 1, log corrupted.

From the survey data, I can for sure say I have the 10cm offset in height with TOPCON ntrip, also the XY coordinates have a non irrelevant shift. The TPOS points instead looks good, with 1-2cm shift in heigts, all normal.

In that points, i have a know point, the number 1. in my survey, coordinate system was ETRF-2000 and ellipsoidial heights. This is the point coordinates:

Tomorrow I’m going to make other 2 surveys, 1 Topcon and 1 tpos.

Yesterday i was in another region for a survey, about 250km from home, i’ve used TOPCON NTRIP again (but of course connected to another base), and i’ve experienced same thing: after half survey the emlid RS3 stuck, so i needed to reboot. After the reboot, all the previous point were 10cm lower than the points collected after the reboot.

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