Reach RS3: Working with a UHF radio

In our previous post, we shared with you how to get the most out of tilt compensation on Reach RS3. In today’s post, we want to tell you about another feature Reach RS3 has—a dual-band radio.

Reach RS3 combines two radios in one housing which allows you to mix and match RTK receivers you have:

  • LoRa radio is a radio that allows you to set up RTK communication between two Reach receivers set up as a base and a rover, in our case, between Reach RS3 and any multi-band Reach model.

  • UHF radio is a radio that allows you to set up RTK communication between Reach RS3 set up as a rover and a third-party base that also communicates over UHF radio.

Requirements for UHF radio

Let’s look at the UHF radio in more detail. To ensure integration of a third-party base with Reach RS3 over UHF radio, your third-party base should operate in the 410.0 - 475.0 MHz band and support the TRIMTALK450S* protocol. We’ve also developed a specially tuned Emlid UHF 410-470 MHz antenna for increased range, which you can add to the cart along with RS3 at the time of purchase in our store.

How to set up RTK communication with third-party base over UHF radio

To set up RTK communication between your Reach RS3 rover and third-party base over UHF radio, follow the steps from the dedicated guide in Docs and check out the tips which will help you with the setup and operation:

As for the baseline between your base and the rover, it depends on the transmitter power of the base, Reach RS3 will work with any, but has no control over it.

How to set up RTK connection with Reach base over UHF radio

You may be wondering if you can connect an external UHF radio to stream corrections from your Reach RS2/RS2+ or Reach RS3 to Reach RS3 via UHF radio. We’re widening choices and have made that possible too. Note that the chosen radio should consider the characteristics of the UHF radio on Reach RS3. Before use, check the specifications.

If you have questions or want to share your experience, leave us a comment below and contact us at

*TRIMTALK is a trademark of Trimble Inc.


Do you think the Rs3 will be able to use a Topcon Hyper V as the base and connect via UHF radios. The specs for UHF hyper V are shown below:

Hoping that there would be some way to connect. Thanks

1 Like

Hi @kencormier.nsls

We haven’t tested this particular device, but I checked your screenshots and Googled this PDF for more details. Based on that, the device meets the following main criteria:

  • Working on 410-470 MHz
  • Supports the Trimtalk protocol
  • Sending the correction in RTCM3 format

Ok. Thanks for your input. I will be testing soon and report back on testing. Have a great day.


Thank you! We will be waiting for your results!


Can the RS3 work as a base with the same specular setup (third party rover)?

1 Like

Its designed to only receive the uhf corrections , It cant broadcast uhf


David is right. You can use Reach RS3 only as a rover via UHF. To use it as a base, you need a third-party radio to send the correction.




Hi @kencormier.nsls,

Have you had a chance to try your Topcon receiver with Reach RS3 via UHF? Do you need any help with the setup?

1 Like

I did try but did not have any luck, unfortunately. If you know the procedure I hope that you can share it with me. I am in the final process of deciding to purchase the RS3, and I could make it work with my Topcon uhf, that would convince me to purchase. Please advise

1 Like

Please set up everything again and take screenshots of the settings of both units. After that, please download the full system report of Reach RS3 and send everything to us at I’d like to take a look to see what could be the source of the issue.


We use the GR5 in conjunction with the RS3 and it works perfectly.
Just be aware of the protocols, formats and frequencies. I don’t see much difference with Hyper V.

we also connect it to the R8


Thanks for your comments

1 Like