Which time standard is used?
Which time standard is used?
When the time is set based on GPS, is it set to UTC in the RTC, or to GPS time, which does not include leap seconds?
Re: Which time standard is used?
My question was about whether the time set in the radio after the GPS sync is real UTC or the GPS time, which is differs from UTC with a few seconds.
Re: Which time standard is used?
If the time is synched from the GPS module then it uses the NMEA sentences sent from the module.
NMEA specifies that the time is UTC, so the leap second adjustment from GPS time to UTC should have been done by the module.
I don't think that anyone has ever checked this though. If it is really important to you then you will need to check it yourself by comparing the radio time to a known UTC clock.
Colin G4EML
NMEA specifies that the time is UTC, so the leap second adjustment from GPS time to UTC should have been done by the module.
I don't think that anyone has ever checked this though. If it is really important to you then you will need to check it yourself by comparing the radio time to a known UTC clock.
Colin G4EML
Re: Which time standard is used?
The firmware is not designed to be an accurate chronometer
the internal RTC in the MCU drifts
Synchronisation with the GPS time will only be accurate to about +/-1 second of the value from the GPS module
The official GPS modules fitted in these radios are cheap low quality devices, and should not be relied upon for accurate timekeeping
The reason the clock functionality was added to the firmware was to support satellite operation, where accuracy is only required to about +/- 15 secs or possibly worse.
The reason time keeping does not need to be incredibly accurate for satellite operation is that the satellite orbits are not precise, so a few seconds of inaccuracy in the radio makes no difference in the ability to contact the satellites
the internal RTC in the MCU drifts
Synchronisation with the GPS time will only be accurate to about +/-1 second of the value from the GPS module
The official GPS modules fitted in these radios are cheap low quality devices, and should not be relied upon for accurate timekeeping
The reason the clock functionality was added to the firmware was to support satellite operation, where accuracy is only required to about +/- 15 secs or possibly worse.
The reason time keeping does not need to be incredibly accurate for satellite operation is that the satellite orbits are not precise, so a few seconds of inaccuracy in the radio makes no difference in the ability to contact the satellites