JMC update on GPS receiver rollover

JMC GPS receivers calculate the date based on the week number included in the GPS satellite signal. Week numbers of satellite signal start at Week 0 and fill up to Week 1023 and reset to Week 0 at Week 1024 (after 19.6 years). Therefore, the time of the clock in the GPS receiver may be reset, which may cause an incorrect date display on marine equipment. This phenomenon is called GPS Rollover. GPS Week 0 started on January 6, 1980. The 1024 weeks counter ran out and rolled over on 21st August 1999. The week counter then reset to zero and recounted till 7th April 2019, when it was reset again. The next reset will be on 21st November 2038.

Many GPS modules’ software has this problem resolved by setting of Internal Rollover as above. The status of GPS Week Rollover and Timing of Internal Rollover for some of the JMC equipment affected is:

  • DG500/T701 GPS Navigator were last adjusted 21/11/2019. The internal rollover for NV08C-CSM v2.x/ v3.x (FW 02xx) is 21/11/2025 and can be extended to 20/11/2038 at JMC factory. For NV08C-CSM v4.x (04xx)/ 5.x (05xx) the date is 06/10/2030.
  • Super Pilot Max Map Plotter & GP-280 GNSS Receiver ANT (products after 2013) were last adjusted 21/11/2019. The internal rollover will be on 27/01/2029.
  • Super Pilot Max III Map Plotter & M8-28 GNSS Receiver ANT were last adjusted 21/11/2019. The internal rollover for firmware 2.01 will be on 23/09/2033. While the internal rollover for firmware 3.01 will be on 9/10/2035.
  • RT-2501G Marine Radio internal rollover will be 1024 weeks (19.6 years) after firmware release.

NOTE: All JMC products certified complying with latest SOLAS requirements for Navigation Sounders and NAVTEX Receivers are not affected by GPS Rollover.

Since its establishment in 1969, Japan Marina Co., Ltd. (JMC) has been a devoted manufacturer of marine electronics equipment. A reputation for providing quality professional products and services is well-earned and respected internationally in the areas of fishing and maritime navigation.

Today JMC manufactures and markets products and systems for all sizes and types of commercial fishing ships and merchant marine vessels. Products for GMDSS and EU MED (wheel-mark) approved equipment are marketed under own JMC Brand or supplied to major marine electronics companies on an OEM basis.

For further information you may contact the Official Distributor and Support Center for Greece:

 

Aegean Electronics SA

4 Zosimadon Str, Piraeus 185 31, Greece

Tel: +30 210 4123000

E-mail: info@aegeanel.com