Ntrip question for Brian?

Trying to verify my NTRIP settings. I see the data coming in, but would like to compare pre and post NTRIP cords. Can you direct me to this calculation in AOG? I’d like to build a visual line of antenna vs. corrected.

AOG doesn’t do any calculations on ntrip, it just passes the info back up the serial port to the gps and what aog receives is the corrected values.

Well, that explains why I couldn’t find it. I’ll go back to school on Ntrip. Thanks.

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I have setup a base station at the yard using an Ardusimple board and an ESP32 with ESPRTK, which updates rtk2go.com.

I was hoping to use this to give me my RTK correction in the field via 4G / my existing long range WiFI network to my tractor. I am currently using a Deere Starfire 3000 receiver, and its serial output… I was assuming that this would stay the same and that AgOpenGPS would login via ntrip and correct the position data, is the right? Or am I reading the above correctly and thinking that is not the case, and that for RTK correction I would also need to use an ardusimple unit or similer at the rover (tractor) end also and let that connect to the base station and provide a corrected NMEA output to AOG?

All that AOG does is pass on the corrections to the GPS unit which is set up to use that correction data to output corrected NMEA. You would have to use RTKLIB etc to do corrections if your gps unit can’t.

That would answer why my Ntrip appears not to work. Because it is not working. I’m getting data but my cheep GPS …

Thanks again Brian.

That makes sense. Was hoping to use my SF3000 unit as it outputs the correct nmea stream with roll etc already compensated for, but thats not going to work I dont think as cant imagine there is any way to pass the RTK onto the Deere unit.

Anyone know if theres a way to use a ardusimple or something as a serial pass through using incoming NMEA data, and RTK correction to correct it and output a corrected NMEA stream ?

@darrenjlobb There is this discussion How to use ZED-F9P as a base station for Trimble | The Combine Forum but not for Jd. It might give you a few clues though

Thanks Brian,

Looks like it is possible to send the corrections with RTCM via the serial to the SF3000 unit, and several have already done this, however for it to work, the receiver has to be unlocked with the Mobile RTK activation, which is an annual sub! So looking like I might have to scrap that idea and just run another ardusimple in the tractor and add the terrain compensation to the PCBV2.

Unless anyone knows a way I can interrupt the serial stream and correct it on the fly with another board?

Is it something AOG could do in future Brian? IE take raw NMEA stream from receiver as normal via serial, and then correct it in the application with NTRIP?

No this isn’t possible. NMEA doesn’t provide near enough of the kind of information needed to perform RTK calculations. You can do it with raw RINEX data from the receiver, or by getting raw data from the receiver via ublox command protocol, and then process it it using RTKLIB. This is what the Reach RS units did. The F9P doesn’t need any of that because it does the RTK stuff onboard. A way cheaper way to go, even if you have existing hardware.

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Makes sense now, I did a little more reading up last night and came to same conclusion. Think I will just buy a pair of F9P based devices and antennas and religate the SF3000 to the combine only (Only because it has autotrac / activations etc already on it) otherwise id be looking to do the same on that to!