Hi all,
Just got a FACET and setting it up with SW Maps (IOS) all seems to work but then when I connect to Geodnet RTK, I get a connection but the accuracy doesn’t improve. I messaged Geodnet and they say SW Maps is sending them a strange location in the middle of the ocean (lat 4.99… long -79.74…) any ideas what might be going on??
Thanks in advance.
That location is indeed in the ocean, but not “in the middle”. What location are you sending them?
Before using RTK, your receiver must establish its approximate position via NMEA protocol based on satellites without using a base station.
Once the receiver establishes its approximate position, it sends a GGA message to Geodnet so that it can assign it the nearest RTK base station.
The Sparkfun Facet exposes two USB-serial interfaces:
In SW Maps:
If everything works out and you have an open sky without obstacles, you should have Fix type: RTK Fix.
Looks like it might be a bug in SW Maps for IOS?, when I borrowed a friend’s Android Phone and set it up, the accuracy was 1.1cm H and 1.9cm V (RTK Fix).
Sorry, I’m not an expert. It looks like RTK won’t work over Bluetooth because iPhone doesn’t support Bluetooth SPP.
The only solution is to set up a WiFi connection. You need to set Sparkfun Facet to WiFi AP mode, connect your iPhone to a WiFi network and configure Networked GPS in SW Maps settings.
@grw , The Facet will work fine with SW Maps on iOS.
You will need to change the Bluetooth mode (on the Facet) to BLE to to communicate with iOS.
Yes, I did that. It looks like the issue is with SW Maps sending the wrong coordinates to Geodnet (NTRIP) and they are sending corrections from a very distant server and the accuracy never improves. I have sent a note to the SW Maps developer but have not heard back. All works well with Android.
You could look at the serial output, to confirm the NMEA GGA sentences are correct coming from the Facet…which I expect to be true.
After that, you can check to confirm “Send NMEA GGA to Caster” is turned ON in the SW Maps NTRIP Client Setting.
A long shot : change the NTRIP Versions (V1/V2) in the SW Maps NTRIP Client Settings…but I doubt that’s going to make any difference for your issue.
I just checked a few different NTRIP Casters after Updating SW Maps on my iOS device…SW Maps still works properly for me.
This sure looks like a SW Maps IOS Version (Ver 1.2.3) issue, Geodnet gave me the mount point for the nearest server and it works. The accuracy is 14mm H and 26mm V. I have let the developer know.
Yes, there is a problem with SW Maps IOS. For version 1.2.3 it says “Minor fixes for NMEA GGA output to NTRIP casters”.
If this is fixed, you can try configuring it according to the guide iOS - SparkFun RTK Product Manual