Welcome to Weather-Above
The PC Clock synchronization program.
The NMEATime application program will automatically set the PC clock to the time from the GPS receiver.
NMEATime
To keep weather-above computer system clock accurate we use a GPS Receiver SiRF Star 111
We are using a utility called tardis this program synchronises the system time using the signals from the GPS unit
Estimate of clock drift
This is an estimate of how much your PC’s clock would drift if Tardis 2000 were stopped now. It may require a long time (hours) before this value will settle down to a reasonable value. It is only going to settle down if you are using SNTP, GPS, or other accurate protocols. The other protocols aren’t accurate enough.
Minimum correction allowed/Adjust clock frequency if below
Tardis 2000 checks that any time correction is worth bothering about. The Minimum correction allowed setting specifies what is reasonable. This is useful if you want to avoid frequent trivial changes to the time that might upset other applications. It is also possible to specify that any correction is allowed by sliding the control all the way to the left. On the service version this option’s meaning changes if the ‘Adjust clock frequency’ is set. When this is set ALL time corrections are used even small ones. They are used to adjust the frequency of the PC’s clock to make it drift less. When this is used the value of this setting determines when the clock is stepped rather than the frequency adjusted. We have the setting set to 20 ms
Maximum correction allowed
Tardis 2000 validates the time received from the server by checking that the amount of correction is not so far out that it must be wrong. The Allowable correction settings specify what is reasonable. This is useful if your timezone is wrong or your timeserver has gone mad. We have this setting set to 1 minute
How often the time is set Every four minutes the system is synchronised
Adjust automatically
If this is set Tardis 2000 will gradually adjust how often it checks the time. This option works in conjunction with the Minimum allowed and Maximum allowed settings. If a correction is less than the minimum the time is increased. If a correction is made the time is decreased. The minimum correction setting effectively becomes the definition of the required accuracy.This is set to on
This information is from the help manual
Tardis
