Survey Manager may exit without notice or it may show some information about the failure, including steps to open a service request with Seequent.

On systems with Montaj 2025.1 or earlier, this issue may be fixed by updating Montaj to the most recent version (2025.2 at the time of this post) and verifying that Survey Manager is at its most recent version (3.5.1433 at the time of this post).

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How do I use this feature?

1. If this is the first time you've used this feature, please read the rest of this post before proceeding.
2. Make sure that you're connected via WiFi to the instrument
3. Go to the Settings page in MagNav
4. Select the "Support" link. 
5. If your instrument supports this feature, the support page will include a link to "Delete project storage". Tap it.
6. You should see a list of projects, with a name and a "Delete project" button for each project. This feature cleans up the data for all of the surveys in a project.
7. Delete any projects for which you don't want to keep the in-instrument data.   You can delete the data for all of the projects that you see, but there's no harm in leaving the files for projects that you're still using.
8. Some projects will show a name similar to this: . These are early projects, in which the user-assigned name was not used in the instrument storage.  It's OK to remove the data for these projects.

Why do I need to do this?

The magnetometers that use MagNav first store data on the instrument, and then sync (or download) the data to MagNav.  Some instruments, for which this technical approach makes the instrument more reliable - MagEx, e.g. - do this automatically. Other instruments, such as those that allow disconnected acquisition (e.g. MagStation), store the data until the user re-connects to the instrument and manually starts the sync process.

The data stored in the instrument is not of any use once it's been downloaded, but because deletion is slow and for other technical reasons, it's left on the file system in the instrument.  As it accumulates, it could eventually interfere with the performance of the instrument and should therefore be deleted.

Will this delete any data in the database in MagNav?

No, this feature doesn't remove or change any data in the database in MagNav.

When should I use this feature?

Here are a few guidelines:

• Run this utility after deleting an entire project.
• Run this utility after completing a long field survey.
• Run this utility while doing other instrument maintenance.
• Run this utility after you've collected "a lot" of data.
• Run this utility when you have the impression that the instrument is unresponsive or is behaving sluggishly.

Will anything bad happen if I forget to do this?

Probably not any time soon; the storage systems on the instrument are large and quite efficient. Geometrics tests instruments with amounts of data consistent with several years of regular use, and which show no performance issues relating to file storage performance.

But don't let it go forever; follow the guidelines above.

Can I delete data for projects that I'm still using?

Yes, you can, as long as the data has already been synced to the instrument (that happens manually with MagStation and automatically with the other instruments).  Once the data has been synced and is visible in MagNav, its presence in the instrument storage is no longer needed.

A corollary to this practice is to check the data in Survey Manager before deleting a project from MagNav; there is no mechanism to un-delete a project in MagNav.

The "Eject" feature varies a little from version to version of Android, but is normally found by swiping for the main Android options menus, then finding the USB drive and tapping on a link to "Eject".

• Installing MagNav - For instruments that use the MagNav Android app to acquire data, copy the dot-APK file in the installation package to a USB drive, then follow the instructions in this video from the Geometrics YouTube library: MagNav Installation instructions.
• Installing the instrument software - To install new software in the instrument (the backpack, or wand, or other physical instrument), remove the USB drive from the instrument and insert it into the USB socket on your Windows laptop or desktop.  Run the program setup file; when it asks for a directory to place the file, choose the USB's main or root directory (d:\, or e:\, for example).  Select a simple password (the main purpose of the password is to prevent logins from devices that are looking for open networks), a default channel (4 is a good choice), and let the install complete.  Use the "Eject" functionality in Windows file explorer (to make sure that the install files are correctly written to the USB drive), then remove it from the Windows machine, place it into the USB socket in the instrument, and then reboot the instrument.  During boot-up, the instrument will install the new software that it discovers on the USB drive.
• Installing SurveyManager - Execute the setup file from the release, on the Windows computer on which you plan to run the software.
• Installing MagArrowConverter - If you plan to use the command-line export function for MagArrow data, run the MagArrowConverter setup file.  Because this program is executed from a command line, don't use the default installation path suggested by the install; instead, choose a location that will easy to type, and that doesn't include spaces, for example c:\mag, or something similar.

These anomalies have occurred in data from a few instruments:

• Extra PPS timing signals – Sometimes the PPS sensor in the instrument receives an extra timing signal that’s out of phase with the normal 1-second interval. These are almost always easily identified and discarded.
• GNSS timing anomalies – Very rarely, the GNSS appears to change its mind about the current time or location.  For example, after recording a time at 06:30:21, the next measurement – received one second later – might show a time of 6:30:15 – 16 seconds earlier.
• GNSS location anomalies – A GNSS timing jump may be accompanied by a location jump.

Geometrics’ software now makes additional checks for these anomalies, corrects them when possible, and reports them if they affect the use or visualization of the data.  Some of the checking is in the instruments, some in MagNav, and some in Survey Manager.

Users will notice these anomalies and the functionality to repair and report them in these ways:

• During import or export, the software identifies an anomaly.  If it’s judged to be worth reporting – most likely because it affects the reported locations of magnetometer readings – then it is logged and the user asked to review the log file.
• The user exports data and notices something unusual, for example a discontinuity in the GNSS times or locations.  The customer should review the software’s log files for additional information.

These anomalies are unusual; the type where the GPS changes its mind about the time or location is exceedingly rare and will never be seen by most customers.  The main effect of the new functionality is that the data validation process will now be more visible to users.

A baseball cap often has a little steel button on the top, and for land magnetometers where the sensor is overhead, this steel is very close to the sensor. With movement during walking, this can create strong magnetic spikes in the data. To test this, you can mark the location of the magnetic sensor in relation to the steel button on a baseball cap and record the magnetic field standing still. Then lower the sensor 1 meter and you'll observe the anomaly increase by a factor of 16 or so.

For magnetometer surveys, it is important that the operator is free of electronics and metal. This means no cell phone, no belt, no steel toe boots, etc. Small quality checks can have a big impact on the data and save time in the field.