Operational Instructions Turn on with green key.
Hold down 2 to 3 seconds. Program will open to Main Menu.
Highlight Data Collection
by tabbing with round key and press enter.
Under Data Collection
menu, select Create Rover File if you are beginning data collection.
Under Create File, File
name will appear automatically. Example: R081613A. R=Rover file,
08=month, 16=day, 13=hour in Greenwich time, A=first file in hour 13,
B=second file in hour 13, etc. Keep this file name or change using
keypad and then enter. Tab down to data dictionary, then right tab to
show Data Dictionary menu. Select Generic and hit enter if a data
dictionary has not been created especially for this collection.
Screen will show Start
Feature. Select Point, Line, or Area and press enter.
Datalogger will start
collecting when there are enough satellites and the PDOP is low
enough. There must be a minimum of 4 satellites and maximum PDOP is
set at 8. A comment, such as site number, can be entered at this time
by using keypad and pressing enter.
A point feature should
have a minimum of 60 positions recorded for greatest accuracy of
position. The number of positions taken will show in the lower right
hand corner of screen. When the datalogger has recorded at least 60
positions, press enter. At this time, another point feature can be
taken or press ESC to Exit Data Collection. Use F1 to confirm with
yes. (Note: Use F keys to select options showing on bottom of screen.)
Screen will go back to Data Collection; press ESC to return to main
menu.
If it is going to be
several minutes between collections, it is best to turn the datalogger
off to save the batteries. When datalogger is back a
Main Menu, turn datalogger by pressing green key for 2 to 3 seconds.
If more positions are to
be added to the original file, turn datalogger on, highlight and
select Data collection by pressing enter, tab down to reopen rover
file and press enter. Tab to original file and press enter. Follow
steps from above.
To select files needed, determine
the beginning and ending time of the rover file to differentially correct.
This can be determined by opening
the rover .ssf file in Pathfinder Office, then select View\Time Line and
note hour collection was started and hour ended.
Example: The rover .ssf file
shown on Time Line below would require .zip base files for hours 10:00
through 15:00. (Note last position taken after 14:00)
2) Go to website: ftp://ftp.ncgs.state.nc.us/gps/asheville/
3) Below is an example of what you will see:
Up to higher level directory
dat/ Last update date/hour/year
rinex/ Last update date/hour/year
ssf/ Last update date/hour/year
4) Select ssf/. Below is an example of what you will see:
Current directory is /gps/asheville/ssf
Up to higher level directory
as021306.zip 113 Kb Sun Feb 13 07:17:00 2000 WinZip File
as021307.zip 106 Kb Sun Feb 13 08:18:00 2000 WinZip File
as021308.zip 133 Kb Sun Feb 13 09:18:00 2000 WinZip File
as021309.zip 128 Kb Sun Feb 13 10:18:00 2000 WinZip File
as021310.zip 129 Kb Sun Feb 13 11:18:00 2000 WinZip File
The files names are as follows:
Example: as010101.zip
a = Asheville
s = Standard Storage Format (ssf)
02 = Month
13 = Day of Month
06 = Greenwich
Mean Hour (NOTE: Eastern Standard Time is –5 hours from Greenwich Mean
Time, so a rover file that needed EST hours 10:00 through 14:00 for
February 13 would need base files: as021315.zip through as021319.zip.
Eastern Daylight Time (EDT) is –4 hours from Greenwich Mean Time.)
The .ssf files are
zipped and will be uploaded in that form.
5) Select the files needed one at a time and upload to base folder in project being worked on.