L3 comminications SERIES 5000, Operation And Maintenance Manual

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CHAPTER 4 SonarPro Ver. 11.0 Operating Instructions
Series 5000 Sonar System Operations and Maintenance Manual P/N 11210060, Rev. 13.0
If another operating system other than SonarPro is used, it most likely will not set
the TPU clock. SonarPro should be started before the other operating system to
sync the TPU to GPS time if desired. Once the TPU has been synced, SonarPro
can be shut off and the TPU will continue to keep time with its own clock. Another
solution would be to set the master computer to GPS (Zulu) time.
In the header information for .sds files, there are two times. The first time is that
described above, and again, it is set when SonarPro is started. The second time or
fix time hour, minutes and seconds is the time read from the GPS input on COM2
if a sentence with time is input. This time is not viewable in SonarPro.
4.27.2 IRIG
Some users choose to use an IRIG board to ensure accurate time. The IRIG board
is installed in the TPU as an option. The IRIG board is triggered by an external
IRIG time generator which is synced to a time source, such as a GPS or other
extremely accurate time source. The IRIG board in turn sends a time message to
the TPU on each ping of the sonar, updating the TPU clock time.
4.27.3 Data File Time
When data are stored on a computer running SonarPro, the date and time stamp of
the data files is stamped to the computer that is being used to store the data. The
computer can be either the master or a slave.
For researching data files after surveys, searches, etc., it is recommended to set all
computers used to record data files to the local date and time or to Zulu date and
time.