> 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/trimble-catalyst-da1.md).

# Trimble Catalyst DA1

These steps connect a Trimble Catalyst DA1 to the Premium Positioning correction network over NTRIP, using Trimble Mobile Manager (Android) + a GIS app. 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.
* Trimble Mobile Manager (Android) + a GIS app.
* 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. Check your Catalyst subscription tier: The DA1 is subscription-based, and achievable accuracy depends on the Catalyst subscription active on your Trimble ID. To use a custom NTRIP caster (your own/third-party corrections), you need a tier that permits custom/local corrections and cm-level (RTK) positioning. If unsure which tier you hold, check with Premium Positioning or your Trimble dealer. Tier names change over time, so this guide doesn't name a specific plan.
2. Install the apps and power on the DA1: Install 'Trimble Mobile Manager' (TMM) and the 'Catalyst Service' app from Google Play, plus your GIS app (e.g. ArcGIS Field Maps or QField). Connect the DA1 to your phone/tablet and power it on. Make sure the device has mobile data or Wi-Fi, since NTRIP streams over the internet.
3. Pair the DA1 over Bluetooth: Android Settings > Bluetooth, turn Bluetooth on, scan, tap the DA1 to pair. (Depending on DA1 connection type and TMM version, the Catalyst Service may detect it automatically - then skip manual pairing.)
4. Open Trimble Mobile Manager and sign in: Launch TMM and log in with your Trimble ID (the account holding your Catalyst subscription). This is your own Trimble account - Premium Positioning doesn't provide it.
5. Select the DA1 as the GNSS / position source: In TMM make sure 'DA1' is selected in the GNSS receiver type field and connect to it. The picker wording varies by version ('GNSS source', 'Position source', 'GNSS receiver type') - choose the option pointing TMM at the Catalyst/DA1 rather than the phone's internal GPS.
6. Open Configuration: From TMM's main screen open 'Configuration' (the configuration/settings icon) - where the correction source and reference-frame settings live.
7. Set the GNSS correction source to Custom local: In Configuration, change 'GNSS correction source' from 'Auto' to 'Custom local'. 'Auto' uses Trimble's built-in corrections; 'Custom local' points the DA1 at Premium Positioning's caster.
8. Choose the NTRIP protocol: Under the custom correction settings set 'Protocol' to 'NTRIP' (the other option is typically 'Direct' - leave it on NTRIP).
9. Enter the caster server and port: Server / URL: rtkpremium.xyz Port: 2101. TMM uses these to connect and download the mount point list.
10. Enter YOUR NTRIP username and password: Set the corrections account Username and Password to your NTRIP credentials from your welcome email - unique to your account; do not share them. If a field reads 'if required', it is required for this caster.
11. Select the COMMON mount point: After TMM connects, the mount point list (source table) appears. Select COMMON. If it doesn't load, re-check server, port, credentials and your internet connection.
12. Set the reference frame: Choose the 'GNSS source reference frame' matching the corrections. If unsure, contact Premium Positioning for the correct frame, or select 'Auto'. (Reference-frame wording varies by TMM version.)
13. Set TMM as the Android mock location app: To feed the cm position into a GIS app, Android must use TMM as its location provider. Enable Developer options (Settings > About phone > tap 'Build number' seven times), then Settings > System > Developer options > 'Select mock location app' > 'Trimble Mobile Manager'. Some GIS apps read the Catalyst position directly via TMM and don't need this. (Menu path varies by Android version.)
14. Confirm RTK Fixed and start surveying: In TMM, confirm the receiver is streaming corrections and the solution reaches 'RTK Fixed' with a low, stable accuracy estimate - not Autonomous/DGPS/Float. Then open your GIS app; its position should reflect the DA1's cm-level location. If it stays Float/Autonomous, recheck COMMON, your credentials, the subscription tier, and that the DA1 has clear sky.

### If the fix will not hold

The DA1 is subscription-based: you must hold a Catalyst tier that allows custom/third-party corrections and RTK accuracy, otherwise TMM connects but won't reach RTK Fixed. TMM menu/field labels differ slightly between versions and Android devices - named generically where wording varies. RTK Fixed needs clear sky and a live internet connection.

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.