-A valid 'Lock Time Indicator' is only presented for observations from RTCM Version 3 streams. The parameter provides a measure of the amount of time that has elapsed during which the receiver has maintained continuous lock on that satellite signal. If a cycle slip occurs during the previous measurement cycle, the lock indicator will be reset to Zero. In case of observations from RTCM Version 2 streams, the 'Lock Time Indicator' is set to '-1'. +A valid 'Lock Time Indicator' is only presented for observations from RTCM Version 3 streams. The parameter provides a measure of the amount of time that has elapsed during which the receiver has maintained continuous lock on that satellite signal. If a cycle slip occurs during the previous measurement cycle, the lock indicator will be reset to Zero. In case of observations from RTCM Version 2 streams, the 'Lock Time Indicator' is always set to '-1'.