FreeRTK !
How to set up your own base!
Project maintained by lansalot Hosted on GitHub Pages — Theme by mattgraham
What to buy
The hardware
The GPS
You’re going to need the GPS hardware, and a little computer to run rtkbase, the software that provides an easy to use interface to publishing your own RTK base station.
Some people choose to do this via their PC, but I don’t recommend that, because having your PC running all the time is costly. Also, when you factor in the many vagaries of ublox u-center and SNIP, it can get pretty complicated pretty quickly. rtkbase is a custom operating system that delivers RTK and nothing more. Having a Raspberry pi running costs next to nothing, but even a low-spec PC uses typically over 100W of electricity, and in this day and age, that ain’t funny. Also, think of what you’re setting up as a community resource - just because you’re not using it today doesn’t mean nobody else is; leave it running for everyone’s benefit :)
So, first of all, you’ll need that GPS hardware. This whole thing has come about in thanks to u-blox and their ZED-F9P chips. These are incredibly low-cost, but high-performance devices, and if you hit your favourite search engine, you’ll easily find out why they’re the preferred kit of choice for anyone providing their own RTK services. Do not think that “cheap means rubbish”. These can very easily provide a quality of RTK corrections to match commercial services.
I found the best place to get them was here at Ardusimple: https://www.ardusimple.com/product/simplertk2b/
Get this antenna .
When you order from Ardusimple, you’ll be given the opportunity to pay the import tax, or not - I opted not, and immediately got an email from DHL asking for the cash. So up to you really, think it works out about the same. In total, I paid about £250 tho.
Take note: if you’re thinking about going for different models, then you REALLY want the ZED-F9P, and make sure you’re not buying “just the chip” somehow. You really want that board with the micro USB output, and that “F9P” designation IS IMPORTANT!
Get an antenna extension cable while you’re at it: https://www.ardusimple.com/product/antenna-cable-extender/
The computer
This is the little computer that runs rtkbase - but thanks to the global semiconductor shortages, it can be tricky to find one in stock.
To make life easy, so you can troubleshoot when things go wrong, you really want a computer with monitor/display output, enough USBs to plug in a keyboard, preferably ethernet and wifi. And that pretty much leaves one choice that ticks all boxes: what you want is a Raspberry Pi model 3 (A or B) or model 4. Avoid anything like Pico or Pi zero - and if in doubt, just shoot us a message on the Facebook group.
Here’s the one I bought, a model 3B - it has 4 USBs (you only need one once you’ve finished configuring it), network, wifi and HDMI:
While you’re buying, you should add
- a case for it
- a memory card of at least 8gb
- a micro USB power supply
- You might also need a USB “Micro SD card reader”. You can find these on Amazon if stuck for a fiver. Lots of laptops have these built in tho, so have a look first, you might already have one.
Some other things you’ll need to complete the setup are:
- a USB keyboard
- a TV or computer monitor with HDMI connection
- a network/ethernet cable (if not using wifi)
Reckon on around £50, for all this. Watch out for Rasperry pi models on Amazon that are what you want, but stupid money. Patience and persistence will get you there without paying through the nose.
Some places to check out:
- https://www.okdo.com/c/pi-shop/pi-kits/
- https://thepihut.com/collections/raspberry-pi-kits-and-bundles
Once you’ve got that, you really do have all the hardware you need. So return to the previous page and find out what to check out next.