The Inmarsat-C hardware manufacturer JRC (Japan Radio Company) will be experiencing a GPS rollover for some hardware units on 15th of May 2022.
What is a GPS rollover?
The JRC GPS system is synchronised to a different time scale than Coordinated Universal Time (UTC) and calculates date by counting the number of weeks from a set date – 29th September 2002 in affected JRC units. Due to the size of the counter, the week counter resets to zero after 1023 weeks and begins counting again.
The subsequent incorrect date information on the JRC GPS receiver clocks may result in positioning instability, generating errors in both the GPS position and date. Additionally, the communication function may not work properly.
Who will be affected?
The problem affects some versions of the below model types:
JUE-85; JUE-95SA; JUE-95LT; JUE-95VM
Which units are not included?
JUE 75 – Not affected
Please note: Further details for JUE-75 and the previous rollover can be found here. Please carefully read the information from JRC. This unit has long been discontinued, operators are strongly advised to update their hardware.
JUE 87 – Not affected
What do I need to do?
Positional fix can be restored in most cases by completing a software upgrade for affected units by direction provided of JRC here: http://www.jrc.co.jp/eng/about/news/2021/1224-1.html
Note that not every unit will be affected and, in some cases, no action will need to be taken. However, we recommend following the above URL and clicking the serial number link located next to each unit type to check your step-by-step guide. Further guidance can also be obtained here: https://inquiry.jrc.co.jp/m/gpse_inquiry
If the problem persists, it may stem from failure of the equipment itself, not from the JRC GPS rollover. If this is the case, contact the Pole Star Support team or a JRC authorised marine electronics dealer.
Please do not hesitate to contact Support for any additional information you require.
Customer Support: +44 207 313 7403
Email: [email protected]