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"Good old days"

Some of you may remember the days of TerraSync showing a few GPS satellites in the skyplot. See below a GeoExplorer 2008 happily tracking 7 GPS satellites:

Geo2008, TerraSync

Now, about 12 years later the sky has changed dramatically. 

See below the skyplot at the Christchurch office from the Trimble Planning tool ( :

Skyplot Christchurch, New Zealand

What a change! 

Easily 4 times more satellites of different constellations. And by the way: TerraFlex does not even have a skyplot anymore. Do we still need a skyplot? 


The skyplot was an important tool for planning. With only a few satellites above the horizon it was essential to know how many are left after taking canopy or buildings into account. Out of the 7 satellites from the example above another few are lost quickly behind buildings or other obstacles, ending up with too few to track any position.


Today, having plenty of satellites available it’s almost certain that you’ll see sufficient satellites to track a good quality and accurate position. For most applications there is no need to check the sky or plan for satellite visibility. If you are in a really bad urban canyon and you are not getting enough satellites you may be lost anyway and even the best planning may still not be of great help. 


So, what’s the point of a GNSS Planning Online tool?


Mind the gap, use the gap

It may still be useful for planning extreme environments. Start with the Settings and locate yourself.

However, the best part of it is the educational benefit. 

If you in Chicago for example, you may have a skyplot like this:

Skyplot Chicago

You can instantly see that the satellites are somewhat opposite to our NZ office in the Southern Hemisphere. But practically, how can this skyplot be helpful?


To get most satellites in a tricky canopy location the user of a handheld receiver should position himself or herself north (in the Northern Hemisphere) of the antenna to block less satellites with their own body. Simply because there is the gap of satellites above the North pole anyway. 

User with skyplot

The same applies for mapping features like a tree. What’s the best location for you to map a tree? South of the tree (Northern hemisphere). Then the tree will be north and therefore in “the gap”. 


On the move

Indeed not everyone is aware that the GNSS satellites are moving. A GPS satellite is moving 3.6 kilometers per second or 2.2 miles per second. In the GNSS Planning Tool you can play the satellites movement (upper left, red circle):

Skyplot play

Now you can imagine how the constellation of satellites is changing and there may still be situations when the arrangement of visible satellites is less optimal. in general: The wider the satellites are spread the better it is. However, as said, under normal circumstances you don't need to worry to much about that anymore.


Space weather

In the World View tab or the Charts tab you also get some information about the current space weather. Most of the time it’s not causing issues but sometimes scintillation may occur and that can cause outages of GNSS signals. For information on TEC and Scintillation see here:


In the Satellite Library tab you can also see the status of satellites and if they are healthy or not. 


You can use the tool for planning but also for education (yourself or others) to get a better sense of where the satellites are and what they are doing. It’s not a big deal nowadays and because the tool is easy to use it may take you just 5 minutes to get a sense. 


Enjoy it!

You can use the hamburger menu to switch between the different screens in the Trimble Mobile Manager app. But did you know that you can also tap-and-hold on tiles on the Home Screen to quickly switch to the correct screen?


Screen shot of Trimble Mobile Manager home screen with call-outs of how to switch panes

What do you think? What are the additional features, shortcuts, or UI enhancements that you would like to see in Trimble Mobile Manager? Let us know in the comments.

Does your collected GNSS data not line up with your existing data properly?  Trimble Mobile Manager (TMM) has powerful features to help.  And, to help make it as easy as possible, TMM uses an “Auto” selection feature which makes educated assumptions about how to set it up for you.


This is vitally important in the case your existing data is in a reference frame (datum) which is different from that of a real-time correction source, such as VRS or Trimble RTX.  To make this happen, TMM needs to know the reference frame of any real-time source being used, AND the desired reference frame for the final output position.


This configuration is done in TMM by choosing Menu -> GNSS Configuration



The “Auto” setting can be found in two places:

  1. The GNSS source reference frame setting when configuring a custom real-time correction source

  2. The Detection mode when setting up the GNSS output reference frame 


Auto-selection of the real-time correction source reference frame

The first element of proper reference frame configuration in TMM is to setup the real-time correction source.  Select Custom local in the GNSS correction source setting, and enter the connection details.


With the GNSS source reference frame set to Auto, TMM will select the most relevant current local datum based on the device’s current location.  For example, in the Continental US, TMM will choose NAD83 (2011) Epoch 2010.0 when the GNSS source reference frame is set to Auto.


Often, it’s best to research the reference frame of the real-time source you’ll be using and manually enter those values to avoid any potential discrepancies.  However, in the absence of that information, the Auto selection will likely make the correct choice.  It's important to know that TMM doesn't have the details of your specific custom real-time source, the Auto selection is made based on the current location of the device.


Auto-selection of the GNSS output reference frame

Once the real-time correction setup is complete, finish the setup by setting the reference frame of the output position.  This is done through the GNSS Output - Detection mode.  Similar to the GNSS source reference frame configuration, setting the Detection mode to Auto will select the most current local datum based on the device’s current location.

The DA1 antenna is lightweight and small. It’s easy to use in all kinds of customized configurations!


Using the standard push-fit mount the DA1 antenna can be attached to any 32 mm diameter pole or rod. The standard push-fit 5/8 x 11 pole cap adapter allows the DA1 to be attached directly to any standard survey mounting accessory with a 5/8 x 11 sized thread. An optional accessory kit allows the DA1 to be mounted on different accessories such as a vehicle or off-the-shelf camera-style bipod mounts.


If you want to use the DA1 permanently on a pole you can use the lock-fit adapter. That provides a firmly attached ⅝-inch screw thread to the DA1.


If you want to use the DA1 on the roof of a car or need more distance to a flat surface you should use the tall lock-fit adapter, otherwise the cable may get in the way between the rubber antenna mount and the surface. When using the tall lock-fit adapter you can have confidence the antenna will not come loose with the push-fit adapter in a high motion/vibration environment. 

DA1 on a vehicle


In case you want to use a camera tripod you can use the ¼-inch push-fit mount. A small and simple photo tripod can be used to put the DA1 antenna firmly on the ground (for example when manhole mapping) or it can be used by photographers if they need an accurate position. The ¼-inch adapter also opens up opportunities outside the box.

DA1 on a manhole

The Catalyst DA1 Antenna Mounting Accessory Kit includes these mounting adapters:

  • Replacement rubber push-fit mount and screw
  • Replacement ⅝-inch thread adapter for push-fit mount
  • Locking ⅝-inch thread adapter for DA1 push-fit mount
  • Tall locking ⅝-inch thread adapter for DA1 push-fit mount (suitable for roof mounting in vehicles or other high motion/vibration environments)
  • ¼-inch thread adapter for DA1 push-ft mount (compatible with most common camera tripods/monopods)


Catalyst DA1 Antenna Mounting Accessory Kit

As we know, any field data we collect with accuracy delivered by a real-time correction source will inherit the geodetics of the correction source. That is, the points, lines and polygons that we collect will be referenced to the datum of the correction source. 


In many parts of the world, VRS and other real-time networks broadcast their corrections referenced to a local datum at its reference epoch. That is, the point in time where that datum (and/or realization of it) is explicitly defined. For example, in the United States, that is often NAD83 (2011) epoch 2010.00. This is the complete datum statement as it includes the epoch as the decimal year representation of January 1st, 2010. In some cases, the epoch information may be left off and the reference epoch is assumed.

Note: The epoch should always be confirmed as a missing epoch can also imply current epoch, or the current date. This is more common with global datums such as ITRF2014 and satellite correction sources like Trimble RTX or SBAS.


However, in certain, often tectonically active regions such as California, VRS and real-time networks may use an intermediate epoch, or a date more recent than the reference epoch. Currently, these networks in California use 2017.50 (e.g., CRTN), 2020.00, or even newer. Some networks will even adjust their reference once or more per year.


Typically, the high-accuracy field data you collect will be stored in a GIS system that has been setup with a datum (or more generally, a coordinate system) and the assumption of a fixed, or constant epoch. That way, you can compare data or measure distances accurately over time. But what happens when the data was collected with a real-time correction source that uses an intermediate epoch as we just discussed? What if that intermediate epoch changes over the course of your data collection efforts? Your new data will shift each time the network is adjusted.


The proper way of handling this is to shift the data (positions) in time using time-dependent datum transformations. In this way, we can account for the tectonic movement between epochs (specifically between intermediate and reference epochs) and store our data referenced to a consistent, constant datum and epoch. This feature is available in various Trimble software products including Trimble Mobile Manager (available in the Google Play Store) and can thus be utilized in various field data collection workflows (e.g., ArcGIS Collector).


In order to configure a correction source that uses an intermediate epoch in Trimble Mobile Manager, open the GNSS Configuration screen and locate the GNSS correction source set of controls at the top.

Note: The screenshots below illustrate configuration of a CRTN correction source for Southern California that uses an intermediate epoch of 2017.50.

  • For the GNSS correction source, pick Custom local and use the Server parameters controls to specify the necessary information to connect to your real-time network (protocol, URL, port, mount point, username, password, etc.).
  • For the GNSS source reference frame, pick the specific datum that your real-time network corrections are referenced to. Picking Auto will generally use the most recent realization of the "official" local datum in your region (when it connects to the GNSS receiver). Note that the Epoch control is now populated with the reference epoch value.
  • To set an intermediate epoch, use the Customize epoch toggle to enable the Epoch control for editing. Specify the intermediate epoch value in decimal year format.
  • To set the datum (at reference epoch) that you want to use in your data collection application, locate the GNSS output set of controls at the bottom. In the Detection mode control, you have 3 choices: Same as source (transformation off), Auto, or Select from list.
    - Choosing Same as source will prevent any datum transformation and will send positions to the data collection application directly without horizontal adjustment.
    - Choosing Auto will select the output datum (using reference epoch) using the same logic described above; if the input and output datums, or epochs, are different, one or more datum transformations will be used when sending data to the data collection application.
    - Choosing Select from list will enable the Frame control where you can select the specific datum. Remember that here, the reference epoch will always be used. If the input and output datums, or epochs, are different, then one or more datum transformations will be applied.
    You can also specify a Geoid for calculating orthometric heights as described in an earlier blog post.


For an in-depth discussion of datum and epoch issues (in the context of California), take a look at this xyHt article from earlier this year.

Trimble Mobile Manager (TMM) and apps that use TPSDK (e.g. Esri Collector for ArcGIS) and configuration files created by TMM to configure Trimble GNSS receivers can now compute and output Orthometric Height using a local Geoid file to determine highly accuracy MSL elevation values.


By default, TMM allows you to choose from a list of pre-defined local Geoid files that Trimble maintains and updates from time to time. 


The following list of Geoids is supported out of the box:

  1. AUSGeoid09 (Aulstralia)
  2. AUGeoid2020 (Australia)
  3. Azores Geoid 2014
  4. Brazil SIRGAS Geoid Model 2015
  5. Canada CGG2013A (NAD83)
  6. Colombia Geoid 2004
  7. CR2005
  8. Cyprus Geoid
  9. DVR90 2013 (Denmark)
  10. DVRM (Slovakia)
  11. EGM 2008 Canary
  12. EGM 2008 Costa Rica
  13. EGM 2008 Haiti
  14. EGM 20018 India
  15. EGM 2008 REDNAP
  16. EGM 2008 Vietnam
  17. EGM96 (Global)
  18. EIGEN-6C4 Dominican Republic
  19. Estonia Geoid
  20. FIN2000
  21. FIN2005N00
  22. GEOID12B (Alaska)
  23. GEOID12B (Hawaii)
  24. GEOID18 (Conus)
  25. GEOID18 (Puerto Rico)
  26. Geoide-AR16
  27. GGeoid16 (Greenland)
  28. Guadeloupe - GT et BT 2016
  29. Guadeloupe - La Desirade 2016
  30. Guadeloupe - Marie-Galante 2016
  31. Guadeloupe - Saint-Barth 2016
  32. Guadeloupe - Saint-Martin 2016
  33. Guyane
  34. HBG18 (Belgium)
  35. HVRS71 (Croatia)
  36. Iceland geoid 2001
  37. Italgeo 90
  38. Korean Geoid model in 2018
  39. Lithuania Geoid Model 2015
  40. LV14 (Latvia)
  41. Malaysia Geoid 2004
  42. Minnesota GEOID12B
  43. Netherlands (2004)
  44. Netherlands (2008)
  45. Netherlands (De Min)
  46. Northern Ireland 2015
  47. NN2000 (Norway18B)
  48. New Zealand Geoid 2016
  49. OSGM15 (United Kingdom)
  50. OSGM02 (United Kingdom)
  51. OSGM91 (United Kingdom)
  52. Pl-geoid-2011 (Poland)
  53. Portugal Geoid (GeoidPT08)
  54. RAC09 (Corse)
  55. RAF18 (France)
  56. RAMART2016
  57. RANC08 (New Caledonia)
  58. RAR07 (La Reunion)
  59. Republic of Ireland 2015
  60. RovT4.04 (Romania)
  61. South Africa Geoid 2010
  62. SW172000 (Sweden)
  63. Swiss Geoid 2004
  64. VITEL 2014
  65. Wisconsin GEOID12B


Each time you select a Geoid in TMM, the Geoid file will automatically download to the GeoData folder, and will remain on your device unless you reset or delete the folder. Depending on the speed of the internet connection on your phone and Geoid selected, the file may take some time to download as each Geoid file can vary in size from 1-2 MB up to a 100 MB or more.


If your required/preferred GEOID file is not present, you can copy a Geoid file to the system storage on your device, specifically to the GeoData folder. After copying the GGF file to the GeoData folder, it will become available in the GEOID list in the TMM. Simply select it from the list and TMM will store this in the configuration file it uses to connect to the Trimble GNSS receiver. 

For more details on configuration Esri Collector for ArcGIS using Trimble Mobile Manager, refer to our 4-part blog series here, which goes into a lot more detail.

A Panasonic survey from 2018 has shown that a lot of professional customers don’t know what an IP rating stands for. 40% believe the X in IPXY is a rating for energy efficiency. 

Although ruggedness is seen as an important requirement, the terminology is confusing. You don’t need to become an expert though. Here are the 2 most important standards.


IP rating by the International Electrotechnical Commission (IEC60529)

The IP rating is a standard for ingress protection. The first digit stands for solid particles, the second digit for liquids. 

Most rugged devices are between IP54 and IP68. 

It is not only that a higher number is better. A device with IPX8 (immersion in water) may actually fail a water jet (IPX6). So, it depends.

Many smartphones are IP rated nowadays. They have gone through the same laboratory tests as a “rugged” device. Rugged devices have a much more robust design. There is simply more material and it does not rely on a hydrophobic coating. This coating may lose its effectiveness over time. Apple actually denies warranty cover with liquid ingress. IP rating for phones is a great thing but it's not designed for the same durability. 

Which IP rating should you buy? Well, make sure you have an IP rating. IP54 is the basic level to claim ruggedness. IP X8 means you can theoretically dive with it (1m). But why would you? You can accidentally drop the device into water, you can wash it in a puddle of water if it got dirty, and you know for sure you can work in rain. Not once, but over the life of the product. And that’s the difference between smartphone IP rating and rugged device IP rating. 


MIL-STD by the United States Military

Military standard. That must be rugged!

The MIL-STD for “ruggedness” is -810. There are many other MIL-standards. There is a tiny difference in what manufacturers state: Tested to MIL-STD or simply “MIL-STD” or “designed for…”. Products can be designed for MIL-STD-810 without even being tested for it. It’s also important to note that the tests are also laboratory tests only. 

The MIL-STD-810 is a good assembly of tests to confirm the product is rugged as long as the tests are done p[roperly and preferably by a certified laboratory.. If you want to be really sure what exact test is used you’d need to look up the test, the method, the procedure, the category and also the version of the revision, but that means you become an expert. Therefore: If the manufacturer is specifying vibration, then that means someone was at least thinking about vibration. The test should also be done by a certified laboratory.

An example highlighting some of the dependencies are drop tests. The test is mostly done dropping the device on all edges, faces and corners. If in real life the device is dropped and hits a rock with the display, it will probably break. The drop test can refer to MIL-STD-810. However, there are no drop tests for GNSS receivers in the MIL-STD. Here the manufacturer should provide a 2m pole drop test although there is no standard for that. It can still be aligned with MIL-STD tests though.

The most common tests are: Operating and storage temperature, drop, humidity, vibration, and altitude.


At the end of the day it’s a decision as to whether you trust the manufacturer that they comply with the standards being claimed. It’s good practice to state to what standard the test has been done (e.g. IEC60529 or MIL-STD-810)  If standards are claimed it is likely that the product will indeed meet and exceed or at least get close to that standard. 


There are plenty of other certifications like RoHS, WEEE, FCC, CE, REACH. These are regional environmental or regional safety certifications.

What do both the West Virginia Department of Environmental Protection and the Koochiching County Office of Land & Forestry in Minnesota have in common? Both have successfully introduced high accuracy Trimble GNSS receivers to their everyday field workflows on Avenza Maps Pro.


In this webinar we hear directly from each group on how the Trimble and Avenza Maps technology solution has improved daily operations, reduced time in the field, and mitigated errors.


  • Learn about the combined Avenza Maps Pro and Trimble solution workflows
  • Gain more insight into business improvements in the forestry, land management, and environmental industries through real customer examples
  • Hear directly from a GIS team lead and assistant land commissioner on why Trimble and Avenza Maps have the best solution for their needs


Watch the on-demand recording here.



  • Danae Schafer, Assistant Land Commissioner, Koochiching County Office of Land & Forestry Minnesota
  • Nick Schaer, senior mining geologist, senior Karst geologist and mobile GIS team lead, West Virginia Department of Environmental Protection (WVDEP)
  • Tristan Lyttle, Product Operations Lead, Avenza Maps
  • Stephanie Michaud P.Eng, Strategic Marketing Manager, Geospatial Field Solutions, Trimble Inc

Trimble Catalyst is a cost-effective way to precision enable any smart-phone based field workflow. It uses a small, light, and low-cost antenna which plugs into compatible Android phones and tablets via USB, and runs a clever standalone GNSS receiver using the CPU of the phone to generate high-accuracy position data without the need for or use of a hardware GPS receiver.  Using the "location sharing" feature of the Android operating system, or by using the Catalyst SDK to build support for Catalyst directly into your app, high precision GPS data (down to 1 cm RTK) is achievable in any location-enabled app.


The On Demand feature allows you to access Trimble Catalyst hour-by-hour. This means that you can pre-purchase time credits in advance, and then use them as needed hour-by-hour. 


Catalyst On Demand accounts can be shared with as many users as you need to support - meaning that you can operate a single shared 'pool' of time-credits, and then nominate who in your team you want to share the pool with. Sharing a pool is managed using the Trimble License Manager interface, and simply means recording the email address of each user you want to share the pool with.



Users only need a Catalyst DA1 antenna, and Android phone, and the Trimble Mobile Manager (TMM) app installed on their phone to use the service. When they run the TMM app, they sign in with their email address, and Catalyst recognizes the user as the member of the pool and presents the interface to draw down licenses hour-by-hour. 



If you have a large organisation, and want to be able to share the pool across the entire team, you can do so simply by enabling the "Share with my domain" feature in the License Manager. With this switch enabled, any user with an email address with the same domain (the part after the @ symbol in an email address - e.g. will be able to access the pool and draw down time.  This prevents you from needing to specifically identify every single user who may be utilizing the account.




You can keep track of who is using your account with the usage feature, which generates a simple report of where your On Demand hours are being utilized. The report can be downloaded and viewed/analyzed in your favourite spreadsheeting tool.



You and your team can continue using Catalyst On Demand so long as your pool balance is above zero. When the balance reaches zero, you need to top up your account. You can also use the License Manager to set a reminder for yourself to top up at any time once the pool balance reaches a certain limit.

There are three different options for how your current location is formatted on the Location Status screen in TerraFlex:

                   Decimal Degrees                                 Decimal Minutes                           Degrees, Minutes, Seconds


You can choose your preferred format by tapping on the POSITION heading to cycle through the different options:

Watch an informative webinar to learn how the Colorado Department of Transportation (CDOT) surveyors and Subsurface Utility Engineering (SUE) managers successfully paired Trimble GNSS receivers with the ProStar PointMan mobile app to collect survey-grade utility locations and export the data into their Bentley MicroStation projects for precise, industry grade asset locations in utility, construction and survey specific workflows.


CDOT, along with many other DOT agencies, employs a specific utility coding system to manage its various utility assets as well as for easy standardized stylization.


  • Learn about the combined PointMan and Trimble solution workflows
  • Gain more insight into the utility, survey, and construction markets through a real customer example with CDOT
  • Hear directly from a CDOT Utility and Railroad program manager on why Trimble and ProStar have the best solution for their needs




Rob Martindale, PLS, Program Manager, CDOT Utilities and Railroads, CDOT

Ben Skogen CPM, PointMan Product Manager, ProStar

Stephanie Michaud P.Eng, Strategic Marketing Manager, Geospatial Field Solutions, Trimble Inc


Watch a recording of the webinar on demand here.

As you know, Trimble Positions Desktop add-in stores projects and sessions in a database that we keep "behind the scenes" as much as possible. When you first installed the software, you would have used the Desktop Configuration application to create a new database configuration. This is typically a Jet (.mdb) or SQLite (if you installed the drivers) database, but can generally be any ODBC database connection that you've defined. This database has a schema (set of tables) that does get updated periodically as we develop new functionality that requires it. In previous versions of the software when we made a schema change, we required you to use the Desktop Configuration application to first update the schema by clicking the Test configuration link.



As a result of this requirement, we had recommended a "best practice" to be running the Desktop Configuration application after every upgrade just to validate and update the schema if necessary.


Starting at Trimble Positions Desktop add-in, this is no longer strictly necessary. The add-in itself will now self-update the database schema if required by that new version. You will be notified of the schema upgrade requirement the first time you run ArcGIS Desktop with the new version of the add-in loaded. You do have the option to not proceed with the schema upgrade if you would prefer to make a backup copy of the database first. This may be useful in situations where you anticipate a need to rollback to a previous version.



As a reminder, your project data will not be affected during these schema upgrades.

The Template Library stores all the templates you have created within your Trimble Connect project, enabling you to quickly add existing templates to a new map workspace. 

You can select multiple templates from the library to add to a new workspace at the same time. Hold down the Ctrl key on your keyboard and click on the templates from the list. Once you’ve selected them, click the Use button to link those templates to the workspace, or choose the Duplicate option if you want to make copies of the original templates.


You can bookmark your favorite map workspaces from Trimble Connect directly in your browser. When you need to open a map workspace click the bookmark and you’ll be taken straight there, you don’t load them through the Trimble Connect application first!


The TDC150 is a fully integrated, high-performance, easy-to-use handheld GNSS field computer for GIS data collection and management. With flexible accuracy options, this fully rugged, versatile device is ready for all of your field data projects.

In the webinar Trimble Mapping & GIS expert, Dan Colbert, discusses:

  • The key features/benefits of this device and how they can help you be more productive in the field
  • Choosing the right accuracy option to suit your workflow
  • How to maximize handheld-only use even when accurate positioning is required with a virtual pole system


Watch a recording of the webinar on demand here.