Weird Height Difference for GCP


I’m currently using 4 Reach RS+ for vessel heading checks and need to verify the Latitude, Longitude and Ellipsoidal Height for when they are used in the field.

3 of the systems are almost perfect; they produce LLH differences of less than 5 cm which is well within our own specifications as well as the Standard Deviation being less than 0.01.

However, one of the systems produces sub-5cm Latitude and Longitude differences with corresponding SD’s of less than 0.01 (which is fine), but on closer inspection of the Height SD, it is currently at 14cm, which is well out of specification!

I have plotted a time-series for each individual point and the height difference starts at positive 30 cm, then varies to -20 cm.

In addition to this, the satellite quality is non-existent and I have performed a ‘factory reset’ of sorts, reflashed the unit and entered NTRIP details in again, but to no avail :frowning:

Any ideas?

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