> For the complete documentation index, see [llms.txt](https://docs.premium-positioning.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.premium-positioning.com/guides/leica-gs18-t-gs18-i-gs16.md).

# Leica GS18 T / GS18 I / GS16

These steps connect a Leica GS18 T / GS18 I / GS16 to the Premium Positioning correction network over NTRIP, using Leica Captivate (CS20 controller). They assume you already have your NTRIP credentials.

### Before you start

* Your NTRIP username and password, from your Premium Positioning welcome email or your account on the customer portal.
* Leica Captivate (CS20 controller).
* A working internet connection on the controller or phone.
* A clear view of the sky at the point you are measuring.

### Network settings

These are the same for every Premium Positioning customer. Only your username and password are unique to you.

* Server or host: rtkpremium.xyz
* Port: 2101
* Mountpoint: COMMON
* Protocol: NTRIP

### Steps

1. Power up and pair the receiver: Turn on the GS18/GS16 and the CS20 controller. In Leica Captivate, make sure the controller is connected to the GS receiver (it should appear connected on the Home screen). Confirm you're in a job/coordinate system before starting RTK.
2. Get the controller online: From Captivate Home go to Settings > Connections and open the internet connection setup ('Internet connection' / 'GS connects to internet' depending on version). Use the CS20 SIM/cellular or a Wi-Fi hotspot. The rover needs working internet before it can reach the caster.
3. Open the RTK rover setup: From Captivate Home go to Settings > Connections and open the RTK rover connection ('RTK rover wizard', or 'GS RTK rover' / 'RTK Network profile' in newer versions). Create a New profile (or copy an existing one). Set the RTK rover to connect via the Internet.
4. Create the RTK / NTRIP profile: Name the profile (e.g. 'Premium Positioning'). When asked for the connection/data device, choose the controller's internet connection so corrections come over the Internet rather than a radio.
5. Set the connection type to NTRIP: For the network/server type choose NTRIP (in some versions the choices are 'NTRIP' vs 'Direct IP' - select NTRIP).
6. Enter the caster server and port: Create a New server and enter Host / Server: rtkpremium.xyz and Port: 2101. Leave the protocol as NTRIP. Save the server so it can be reused.
7. Enter YOUR NTRIP username and password: Enter the NTRIP User ID and password from your Premium Positioning welcome email - unique to your account; do not use anyone else's.
8. Select the mountpoint: Use COMMON. If Captivate offers 'Select mountpoint from source table', loading it also confirms the login works - pick COMMON. If the source table is slow or comes back empty, type COMMON manually in capitals; with large source tables this is normal Captivate behaviour, not an error.
9. Turn on Send GGA position: Set 'Send GGA position' to On or Automatic - the COMMON mount needs your rough position to compute corrections. If this is off you may stay on Float and never reach Fixed.
10. Finish and save the profile: Step through the remaining wizard pages (PIN/PUK and device questions can stay default for a standard internet rover), confirm the summary, and press Next/Finish (F6) to save.
11. Start the connection: Select your saved RTK profile to start it. Watch for 'Connected to internet' then 'Connected to NTRIP caster'. If login fails, recheck the username/password and that the host is rtkpremium.xyz on port 2101.
12. Confirm an RTK Fixed solution: Watch the status bar progress Navigated/Autonomous > Float > Fixed, with Coordinate Quality (CQ) dropping to cm level. If it stalls on Float, check Send GGA is on, you have clear sky, and your internet is stable.

### If the fix will not hold

Menu/button names vary between Captivate versions (e.g. 'RTK rover wizard' vs 'GS RTK rover' / 'RTK Network profile') - match by meaning. If you can't reach Fixed, the usual causes are an offline controller, wrong/blank credentials, Send GGA off, or poor sky view. Distinct from the Leica iCG70 entry, which is the iCON machine-control line.

For more, see RTK corrections troubleshooting and Fix inconsistent RTK accuracy on site.

### Need help

Support is available 24/7. Include your receiver model, the mountpoint, the solution status, and the correction age when you get in touch.