From drone pilot to RTK provider: why we started RTKsub
We were already selling the base stations. The question was who would sell the corrections to the people who actually need them.
I did not plan to run a positioning service. I studied land and water management, joined the family groundworks company, and at some point started flying drones to map our own sites. That is where it began.
The first time I needed a centimetre
A drone map without RTK looks great and lies to you. The pictures are sharp, the model is beautiful, and everything sits a metre or two from where it should be. For a volume calculation that is a problem. For a site plan it is useless. The fix is RTK: a nearby base station, a correction stream, and suddenly every photo knows where it was taken to the centimetre.
Getting that correction stream turned out to be the hard part. Not technically. Commercially. Corrections were sold per country, per year, with a contract, a sales call and a price set for large survey firms. I wanted to try something on a Tuesday and pay for a month.
Meeting a network built by its users
Around the same time, through FreshMiners, our hardware shop, we started selling GEODNET base stations. GEODNET is a decentralised network: people host a station on their roof, the station streams GNSS data, and the host earns a reward. Thousands of stations went up this way, in places where no government network would ever bother to build one. We were putting those stations in boxes and shipping them across Europe.
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That is when the question became obvious. We sold the stations. Who sold the corrections to the drone pilot, the contractor, the farmer with one tractor? Nobody we would recommend to a friend.
August 2025
So my business partner Yuri and I built it ourselves. RTKsub went live in August 2025. A free trial, a monthly plan, a yearly plan. One network. A Dutch company sending the invoice. Support answered by the people who built it.
The first months were humbling. We thought the work was the service. The work was the devices: every drone and rover has its own idea of how NTRIP should work, and we learned them one support email at a time. We wrote guides. We built an assistant, RTKgpt, so people do not have to wait for us. We learned to say “there is no station near you, don’t subscribe yet”.
What we believe
GPS gets you close. RTK gets it right. And the “right” part should be as easy to buy as a phone plan. No country borders, no yearly contract before you have seen a single FIX, no sales call. Try it, see it work on your own screen, then decide.
Where this goes
More stations, because every host who puts one up makes the network better for everyone around them. More devices that work out of the box. And more of the same: honest answers, a trial first, and people who reply.
If you fly a drone or run a rover and have never seen the status flip from FLOAT to FIX, go see it. The trial is free at rtksub.com.
