H520e-RTK stuck on 3D Fix with own RTK base — RTCM data received but no RTK convergence

TomEnde · 2026-06-22T15:46:39-0400

Hi,

I've built a custom RTK base station (Raspberry Pi 5 + u-blox F9P) and connected it to my H520e-RTK via ST16E ground station over WiFi.

Setup:

NTRIP server: 192.168.4.1:2101/BASE0
RTCM output: 1004, 1005/1006, 1012, 1019, 1020, 1033, 1077, 1087, 1097, 1127, 1230
Throughput: ~300-400 bytes/sec (stable)
ST16E: NTRIP connected, shows "receiving RTCM"
Drone GPS: 31 satellites, good signal

Problem:
Drone remains at 3D Fix. No RTK Float or Fixed achieved, even after 5+ minutes of stable RTCM stream.

Questions:

Does H520e-RTK require specific RTCM message types beyond standard?
Any known antenna height / ARP offset settings needed?
Should I use TCP (5016) instead of NTRIP (2101)?

Any pointers appreciated.

h-elsner · 2026-06-23T02:48:36-0400

I have no experience with RTK network setup but I wonder if server IP 192.168.4.1 is correct? Isn't it the same IP address as the camera has? Same address in the same network will not work.

TomEnde · 2026-06-23T12:43:46-0400

the point is:

My PI makes a own AP wifi network where my st16s is connected to, throug ntrip_caster from stefal. then from the st16s through ofdm to the drone. but that's not working perfectly. and in case there is no good support anymore for Yuneec in europa (Sadly) i dont know how to use it and what for things Yuneec needs for RTK..

TomEnde · 2026-06-23T13:02:28-0400

TomEnde said:
Hi,

I've built a custom RTK base station (Raspberry Pi 5 + u-blox F9P) and connected it to my H520e-RTK via ST16E ground station over WiFi.

Setup:

NTRIP server: 192.168.4.1:2101/BASE0

RTCM output: 1004, 1005/1006, 1012, 1019, 1020, 1033, 1077, 1087, 1097, 1127, 1230

Throughput: ~300-400 bytes/sec (stable)

ST16E: NTRIP connected, shows "receiving RTCM"

Drone GPS: 31 satellites, good signal

Problem:
Drone remains at 3D Fix. No RTK Float or Fixed achieved, even after 5+ minutes of stable RTCM stream.

Questions:

Does H520e-RTK require specific RTCM message types beyond standard?

Any known antenna height / ARP offset settings needed?

Should I use TCP (5016) instead of NTRIP (2101)?

Any pointers appreciated.

Good question, but it's correct. 192.168.4.1 is the WiFi AP (Pi).ST16E connects as 192.168.4.147 (client) and reaches NTRIP on 192.168.4.1:2101.This is standard local network routing — works fine.

h-elsner · 2026-06-23T14:07:16-0400

OK, understood. I was in the old Yuneec world where the camera is connected over WiFi but H520e the camera connection is OFDM, not WiFi. Sorry, ignore my comment above.