In 2023 I started surveying with an RTK Surveyor base and an RTK Express Rover. I used SWMaps for a little while, but quickly shifted to using CHCNav’s LandStar app.
Everything worked great.
In 2024 I upgraded to 2x RTK Facets, base and rover. I also updated the firmware on my Surveyor and Express at that time, everything was running v4.1. With that upgrade the accuracies/errors sent from the units to both SWMaps and Landstar ‘broke’ somehow. I downgraded the firmwares in everything to 3.9. Still failed.
I’m receiving a PDOP/HDOP/VDOP, but not a horizontal or vertical accuracy…
This throws an error everytime I take a shot with LandStar, that I’ve just been dealing with. I know the accuracies are good, because I can reliably stake out coordinates to millimeter accuracy, but the data isn’t being sent.
Any ideas?
rftop
September 8, 2026, 1:49pm
2
The “accuracy estimates” are provided by the GST NMEA sentence. Check your devices to confirm the GST message rate.
In my wi-fi setup, the Message Rates are set to “Surveying Defaults (NMEAx5)”. I assume this should be correct?
I feel like I remember being able to change these in more detail, but I’m not seeing anything anywhere.
This looks like the same issue I’m having, I’ll follow their steps.
Your comment about the message rates is what helped me to find this solution. Thank you!
I have a Facet that’s running RTK firmware version 4.1. I updated the ZED-F9P firmware, using u-center, from 1.32 to 1.51. After the update, the Facet was working okay except SW Maps in its GNSS Status screen was showing “N/A” for the estimated errors and accuracies.
I looked through .ubx log files from the Facet from both before and after the ZED-F9P firmware update. An obvious difference was that before the update, the logs contained NMEA GNGST messages, but they did not after the update. I put the Facet into Config mode and connected a web browser to its WiFi Setup web interface.
I opened the GNSS Configuration menu and then the Message Rates menu, expecting to see the usual, long list of the many different message types and their rate settings, but all that was there were the two buttons for “Reset to Surveying Defaults (NMEAx5)” and for “Reset to Logging Defaults (NMEAx5 + RXMx2)”.
I connected u-center again, and using the Configuration View / MSG menu, enabled the GNGST messag…
rftop
September 8, 2026, 2:56pm
5
In the Serial Menu:
SparkFun RTK Facet L-Band Direct v4.4
** Bluetooth Low-Energy broadcasting as: Facet L-Band Rover-A802 **
Menu: Main
1) Configure GNSS Receiver
2) Configure GNSS Messages
3) Configure Base
4) Configure Ports
5) Configure Logging
6) Configure WiFi
7) Configure Network
p) Configure User Profiles
r) Configure Radios
P) Configure PointPerfect
s) Configure System
f) Firmware upgrade
x) Exit
2
Menu: GNSS Messages
Active messages: 5
1) Set NMEA Messages
2) Set RTCM Messages
3) Set RXM Messages
4) Set NAV Messages
5) Set NAV2 Messages
6) Set NMEA NAV2 Messages
7) Set MON Messages
8) Set TIM Messages
9) Set PUBX Messages
10) Reset to Surveying Defaults (NMEAx5)
11) Reset to PPP Logging Defaults (NMEAx5 + RXMx2)
12) Turn off all messages
13) Turn on all messages
x) Exit
1
Menu: Message NMEA_
1) Message UBX_NMEA_DTM: 0
2) Message UBX_NMEA_GBS: 0
3) Message UBX_NMEA_GGA: 1
4) Message UBX_NMEA_GLL: 0
5) Message UBX_NMEA_GNS: 0
6) Message UBX_NMEA_GRS: 0
7) Message UBX_NMEA_GSA: 1
8) Message UBX_NMEA_GST: 1
9) Message UBX_NMEA_GSV: 4
10) Message UBX_NMEA_RLM: 0
11) Message UBX_NMEA_RMC: 1
13) Message UBX_NMEA_VLW: 0
14) Message UBX_NMEA_VTG: 0
15) Message UBX_NMEA_ZDA: 0
x) Exit
