Trimble Access NTRIP Setup: Survey Style & RTCM3

Connect Trimble Access to RTKdata NTRIP corrections. Set Broadcast format to RTCM3 instead of CMRx, type mountpoint AUTO, port 2101, and clear base data errors.

Trimble Access is the field software that runs on Trimble controllers (TSC5, TSC7, TSC3, TDC6) and drives Trimble GNSS receivers such as the R6, R8, R10 and R12i. It connects to RTKdata over NTRIP, but only after the Survey Style is configured for standard RTCM corrections from a single base station.

Trimble Access connects to RTKdata through a Survey Style. When corrections do not arrive, the receiver and the network are usually fine and the Survey Style is the problem. The most common cause we see is the Broadcast format left on CMRx, Trimble's own correction format, which RTKdata does not stream.

This page covers the Trimble Access side. For receiver-specific notes (tilt compensation, Catalyst licensing, machine receivers) see Trimble R12i / R10 / R750 and Trimble Receivers with RTKdata.

Requirements

• Controller: Trimble controller running Trimble Access (TSC5, TSC7, TSC3 and TDC6 are all confirmed working with RTKdata)

• Receiver: Trimble GNSS receiver paired to the controller (R6, R8, R10, R12 and R12i confirmed)

• Internet: an active data connection on the controller, either the built-in SIM or a phone hotspot. Check that the SIM is inserted and enabled, not just present

• RTKdata account: active subscription with RTK credentials. The NTRIP username starts with rtk and is not your website login

• Open sky: the receiver needs a satellite position before the NTRIP session can complete

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CMRx will not work. CMRx is a Trimble proprietary correction format that only works between Trimble base stations and Trimble rovers. RTKdata streams RTCM3. If the Survey Style is left on CMRx, the receiver expects a data format that never arrives and the connection fails, usually with a base data error. This is the single most common Trimble Access fault in RTKdata support.

Step-by-step setup

1

Create a new Survey Style

1. In Trimble Access, go to Settings > Survey Styles.

2. Tap New and name the style, for example RTKdata Single Base.

Create a fresh style rather than editing an existing one. Styles that were originally built for a VRS or Network RTK service often look correct but keep a network mode set somewhere and stall silently. Starting fresh also rules out leftover settings that quietly override your changes.

2

Set the Rover options

Open Rover options inside the new style and set:

Field	Value
Survey type	RTK
Broadcast format	RTCM3 (also shown as RTCM v3 or RTCM RTK depending on your Access version)
Network type	Single Base or Nearest, never VRS, iMAX, MAX or Network RTK
Antenna / Antenna height / Measured to	Match your pole and antenna setup

If the Broadcast format dropdown shows CMRx, change it to RTCM3 and tap Accept to save. Do not pick a VRS or network flavoured entry: RTKdata delivers observations from a real physical base station, which is what single base RTCM mode expects.

Field labels vary between Trimble Access versions. On older builds the network setting may sit in a separate field, and on some releases the whole mode is presented as a single option named Single Base (RTCM via NTRIP). Pick the entry that combines RTCM with a single base, not a network.

3

Set the Rover data link to the internet

Still inside the Survey Style, open Rover data link and set:

• Type: Internet connection

• Internet source: Controller internet

• GNSS correction source: the RTKdata NTRIP profile you configure in the next step

Do not select a radio data link. The corrections arrive over the controller's internet connection.

4

Enter the RTKdata NTRIP caster settings

Open the NTRIP caster profile behind the GNSS correction source. Depending on the Trimble Access version this opens directly from the Survey Style, or it lives under Settings > Connections and is then selected in the style. In older builds it is a separate connection profile: the Survey Style holds the mountpoint, and the connection profile holds the server, port, username and password.

Select the tab for your region:

North America

• IP address / Host (domain): rtk.rtkdata.com

• IP address (fallback): 13.56.117.10

• IP port: 2101

• NTRIP username / password: From RTK Credentials in the internal dashboard (not website login)

• Mountpoint / Source name (ALL CAPS): AUTO (recommended), or AUTO_WGS84, AUTO_ITRF2020, AUTO_ITRF2014

Europe

• IP address / Host (domain): eu.rtkdata.com

• IP address (fallback): 3.73.41.96

• IP port: 2101

• NTRIP username / password: From RTK Credentials in the internal dashboard (not website login)

• Mountpoint / Source name (ALL CAPS): AUTO (recommended), or AUTO_WGS84, AUTO_ITRF2020, AUTO_ITRF2014

Australia

• IP address / Host (domain): aus.rtkdata.com

• IP address (fallback): 54.206.56.130

• IP port: 2101

• NTRIP username / password: From RTK Credentials in the internal dashboard (not website login)

• Mountpoint / Source name (ALL CAPS): AUTO (recommended), or AUTO_WGS84, AUTO_ITRF2020, AUTO_ITRF2014

The same screen carries a set of yes/no switches. Set them like this:

Switch	Value
Use NTRIP	Yes
Connect directly to Mountpoint	Yes
Use proxy server	No
Use RTX (internet)	No
Use NTRIP v1.0	No by default. Set it to Yes if the connection is unreliable on an older controller

Connect directly to Mountpoint must be Yes. With No, Trimble Access tries to browse the caster source table instead of connecting straight to AUTO, and the mountpoint field offers no usable option. Two separate cases were resolved by this switch alone.

Type AUTO into the mountpoint field in ALL CAPS. Do not select it from a list.

5

Start the survey

1. Go outside with clear sky and wait until the receiver shows a position.

2. Tap Survey > Start survey and pick your RTKdata style.

3. The solution moves Autonomous → Float → Fixed, typically within 30 to 60 seconds in open sky.

If the status sits at "Waiting for information from the base" for a few seconds, that is normal: the controller is connected to the caster and the receiver is still computing the fix. If it stays there and the startup progress hangs, see the troubleshooting table below.

Why there is no station list to browse

Trimble Access users often look for a source table full of station names and find only the mountpoint they typed. That is expected.

AUTO is a dynamic mountpoint. RTKdata reads the GGA position your receiver sends and assigns the best healthy base station near you, then keeps you on it. The routing decision uses live station health and your exact position, so there is no "better" station hidden in a list to pick by hand. That is why the mountpoint is a single stable value typed manually, and why it keeps working when the crew drives to the next job.

RTKdata does not currently offer manual station selection or per-station locking. If your workflow depends on staying on one named base station for the duration of a site calibration, raise it with support before you build the workflow around it.

For coverage planning, see the Coverage Map.

Troubleshooting

Problem	Cause	Fix
"Could not start base data"	Broadcast format still set to CMRx	Open Rover options and change Broadcast format to RTCM3. Confirmed root cause in the same session where the customer read out "Survey type : RTK Broadcast format : CMRx".
"Could not start base data" after the mountpoint AUTO was entered correctly	Server address, port, username or password missing from the connection profile	The mountpoint lives in the Survey Style, the caster details live in the connection profile. Check host, port 2101, and that the username starts with rtk. A blank or website login in those fields produces this exact error.
"Could not start base data" after a controller restart, with settings that worked yesterday	Controller has no live data connection, or the Survey Style reverted	Confirm the SIM is enabled and mobile data is on. One case was resolved purely by enabling the SIM card. If settings changed, rebuild the style from scratch.
"No suitable sources listed" (with a Mountpoint option offered)	Trimble Access is browsing the source table instead of connecting directly	Tap the Mountpoint option, type AUTO in ALL CAPS and confirm. Set Connect directly to Mountpoint to Yes so the source table is bypassed entirely.
"No suitable source" on older Trimble Access	Caster connected, but the mountpoint entered did not match	Type AUTO in ALL CAPS instead of selecting from the dropdown. If the field will not accept free text, leave the NTRIP screen, save, and re-enter it. Backing out and going back in unlocked the field.
"Please sign in" on the controller	The prompt is asking for NTRIP credentials, not the website login	Enter the RTK username (starts with rtk) and RTK password from RTK Credentials in your dashboard. Your email address and website password will not work here.
"Waiting for information from the base", survey stuck near 90% (near 80% on older versions)	Survey Style still in a network correction mode	Set Network type to Single Base or Nearest. VRS, iMAX, MAX and Network RTK wait for a virtual reference station that RTKdata never sends. Correcting Broadcast format alone is not enough, the network mode is a separate setting.
Mountpoint dropdown is empty or shows only a placeholder such as ?	Source table not parsed, or direct connect disabled	Set Connect directly to Mountpoint to Yes, clear the placeholder and type AUTO.
IP address field shows 0.0.0.0 after saving	Caster address did not save	Re-open the field, enter the regional host or IP fallback, save, and re-check before connecting.
Connects and fixes, but accuracy is only sub-meter	Survey type was switched to RT Differential	RT Differential is DGPS, roughly 0.3 m to 1 m. Set Survey type back to RTK for centimeter accuracy.
Connected to AUTO, data is flowing on the network side, but the receiver never fixes	GGA sent once at connect and never updated	The caster needs a continuously updating GGA position. Get a valid autonomous position on screen before starting the NTRIP session, and set NMEA output to a continuous interval (1 Hz is ideal) rather than single shot. A GGA count of 1 in the RTK session history is the tell.
Trimble Access shows Autonomous while another app on the same device gets corrections (DA2 / Catalyst)	Trimble Access takes its position from Trimble Mobile Manager, and TMM's correction source is still on Auto	In Trimble Mobile Manager open Configuration, set GNSS Correction Source to NTRIP and enter the RTKdata caster, port 2101, mountpoint AUTO and your RTK credentials. Trimble Access then picks up the corrected position. See Trimble Unity.

Tips

• Two places, one connection. The Survey Style holds the mountpoint and the correction format. The connection profile holds the server, port, username and password. Most "half configured" cases come from filling in one and not the other.

• Type AUTO, never browse. Every confirmed Trimble Access fix in support used a manually typed, ALL CAPS AUTO.

• Fix the format first. Before changing anything else, confirm Broadcast format is RTCM3. It resolves more Trimble Access cases than any other single setting.

• Rebuild rather than repair. If a style has ever been pointed at a VRS network, delete it and build a new one. Editing in place repeatedly failed to stick in support cases.

• Get outside first. The receiver needs satellites before the NTRIP session can complete, because the caster needs your GGA position to assign a base station.

Related Guides

• Trimble Receivers with RTKdata: the single base versus VRS background behind the Survey Style used here

• Trimble R12i / R10 / R750: receiver side walkthrough, tilt compensation and Catalyst licensing

• NTRIP & GGA Essentials: why the caster needs your GGA position and how AUTO resolves to a base station

• Trimble Unity: the Trimble Mobile Manager route used by DA2 and Catalyst setups

• Trimble Earthworks: machine control setup, which does not enforce the VRS behaviour described above

Related Industry Solutions

• Surveying

• Construction