The world’s clocks will be adjusted by one second on 30 June 2015 when a leap second will be inserted into Coordinated Universal Time (UTC), the standard international time scale. All UTC clocks should insert a second labeled 23h 59m 60s (the leap second) following one labeled 23h 59m 59s UTC.
GLONASS uses UTC in its time system and will also introduce a leap second. The GLONASS leap second will be introduced at 00:00:00 UTC on 1 July 2015. Any potential issues with tracking of GLONASS will be realized at 00:00:00 UTC on 1 July 2015.
Trimble has made every effort to ensure our receivers will work seamlessly through the addition of one leap second on July 1, 2015.  If you are running the current firmware, then resetting the device or reacquiring GLONASS satellites after the introduction of the leap second shoule be sufficient.
Follow these steps to check your GNSS Firmware version:
- Turn on your GNSS device (ie, Geo7x)
- Go to Start/Settings/System or System Folder (depends on the operating system)
- Select System Information
- The GNSS firmware should be listed in this screen
Follow these steps to reset your GNSS receiver:
- Turn on your GNSS device (ie, Geo7x)
- Open your field collection software (ie, TerraSync, GNSS Controller, Trimble Positions Extension)
- Click on Status and go to the Setup Menu
- Click on Options and choose “Reset GNSS Receiver”
- This will delete the alamanc and force the receiver to download a new one
- Let the GNSS reciever run with at least 4 or more satellites for about 12.5 minutes
Trimble Mapping & GIS current GNSS Firmware:
- Geo7X  GNSS Firmware 4.10 or later
- OSÂ Firmware 6.7.16Â (installs GNSS firmware version 4.11.1)
- GeoExplorer 6000 GNSS Firmware 4.02 or higher
- R1 –Â GNSS Firmware 4.96
- Pro6 Series –Â GNSS Firmware 1.04.3
- ProXRT –Â GNSS Firmware 4.71
- Legacy/non-GLONASS products should not be affected
- GeoExplorer Series 2003, 2005, 2008/3000
- ProXT and ProXH
- Juno Series
Please check the MGIS compatibilty chart before upgrading firmware to make sure that your software is supported. Â Feel free contact NEI support if you have any questions.