RTK with no base station. I am clueless!

Hi, I’m new here so please forgive me if this is not the appropriate way of writing this.

I’m very new to the GPS scene and want to try improve the system i was advised to use.

I have an old android tablet with “SixtyFive” app as the map screen.

The app itself is ok, very basic, which suits us fine.

I was advised to purchase a garmin glo as a receiver, which connects via bluetooth to my tablet. The accuracy is nowhere near what it needs to be (not surprising).

I would like to know how I can connect to this via RTK using something like the F9P without the cost of setting up a base station.
I have tried to research and just can’t get my
Head around what i need to actaully do, in order to get an RTK signal.

Just to be clear, this is purely for guidance, no autosteer (yet)

The answer that you don’t want to hear is that you can’t have RTK without some kind of base station that is within ~50km of your position.

That base station can be

  • Your own base station
  • A neighbour’s base station
  • Some stranger’s base station that you found on n NTRIP caster like rtk2go
  • A government base station, like a US State CORS network
  • Some virtual base station that has been calculated for you on some server that has a bunch of real base stations feeding data into it

That base station may be accessible over radio, internet, satellite, the transportation layer doesn’t really matter.

I think the issue that you are experiencing is probably that your Garmen is an L1 only receiver. You want an L1/L2/L5 receiver and RTK.

Thank you very much for your reply.

The problem is the guidance will be used for mainly contract work and doesn’t suit for me to have a base station as i will be far away from it.

If i bought the F9P and didn’t utilise the RTK signal. Would I experience better signal than I currently get?

Thanks again

Is 1.5m accuracy at best good enough for the work you will be doing? If so, you don’t need RTK. If you do need RTK, then you can make a portable base station to take from job to job. A better description of what you are doing on these contract jobs would help with better recommendations.

Hi, no, I’d like something more accurate than that.

Currently using for spraying, fert spreading, general field work.

I would consider a portable base station. But would need to learn more about them before hand.

Check out the excellent training videos by Andy. They will give you a feel for the software.https://www.youtube.com/playlist?list=PL1N2N2XFHWW1fIDhb7koOa7hxH0LGppYc

Check out the getting started section of Discourse. Operations/Getting Started - AgOpenGPS

Sounds like you can’t always guarantee you will be within range of an existing / free base station for RTK corrections when on a job. Look into a portable base station. Just search for “portable base” on this Discourse. Number of threads on making them and usage.

You can get accuracy to somewhere around 4" without a base station with a ZED-F9P and a special satellite receiver. The technology is called SSR. There’s a per-month or per-year fee. Corrections come from a satellite system rather than a ground base station, and coverage is most of north america. ArduSimple has some information on the service here:

Looks like you can get the hardware kit for a little over $500 USD. You will still need to add a bluetooth adapter to the F9P. You cannot use the Xbee slot on the F9P because the SSR radio goes there, so the bluetooth module would have to be wired to the normal TX pin. Not exactly turn key and some assembly and configuration over USB is required.

So it’s possible to get what you want without a base station. Perhaps someone can chime in with a link to a more turn-key version of this hardware.

The 1.5 m must be referring to absolute accuracy. A simple L1 GPS receiver with SBAS (EGNOS, WAAS etc.) correction will give about 20 to 30 cm pass-to-pass accuracy which is sufficient for spraying (normal section control, perhaps not good for individual nozzle control) and fert spreading.

It is inconvenient though as you need to set offsets if repeating the same wayline later on. RTK makes so much more sense even for tasks that do not need cm accuracy, I’d consider a private base if no free base is available as the cost is so low.

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To be honest 20cm would probably be sufficient.
Going back to the same path won’t be something i need to do anyway. Of course the more accurate the better.

What would the f9p be able to achieve that without RTK correction?

Repeatability seems to be the biggest issue. And it’s not something i really need. I keep reading the term pass to pass which is what I think I need.

Thanks for all the responses so far, you have been really helpful.