Facet returning inconsistent elevations

[rftop]

You might not want to bother with this, but here’s a simple way to verify the precision (repeatability) of the System, that everyone can perform:

Install the Facet on a position/point that can be repeated.
Store RTK Fixed solutions only in SW Maps. Do this many times, spread-out over time. The idea is you want different Satellite geometry, different atmospheric conditions, etc.

Export the Points to a spreadsheet with UTM turned ON.

UTM allows you to quickly subtract the smallest value from the entire data set (X, Y, and Z individually).
You can easily see the range of values, because all you are left with are a couple of centimeters over the entire data set (hopefully).

Here’s a link, for iOS SW Maps.

APGLOS GIS iOS Software on iPhone or iPad paired with RTK Facet January 2025

@ChrisO , Here’s what I do for an “easy way” to measure GNSS repeatability using SW Maps on iOS: Establish a semi permanent place to mount the GNSS. Can be as simple as attaching a Rod to a fence post, etc. Store Points in SW Maps over some period of time. You can store single epochs or average 30 seconds, etc… Keep adding stored positions to that Project in SW Maps, over days, weeks, etc. You can Export the Project anytime to check on the repeatability. The Trick is to Export to Spreadsheet AND select UTM as shown below: [image] If you don’t know your UTM Zone, it’s easy to find with Google. With UTM added to the Spreadsheet Export, you get X, Y, Z in Meters in addition to Lat/Long/Z and all the Metadata On your iPhone, Open the FILES App and navigate to SW Maps/Export Folder (I create a shortcut for quick access). Then you can quickly email the Spreadsheet to yourself from the phone. A few calculations in Excel and you have real results on the actual repe…