Gps4 - Gps Position Uncertainty; Mx Ant. Reset & Csi Reset Tools - NorthStar MX500 Operator's & Installation Manual

Operator's Manual

GPS4 - GPS Position Uncertainty

This screen presents a bar graph representing the HDOP for the past
23 hours. If you are trying to do precision work or navigation in the
same general area (within 100 miles) as the day before, you can look at
this screen to see when the best HDOP periods are. The GPS constel-
lation shifts back 4 minutes per day. That means you can expect the
GPS coverage to be virtually the same today as it was yesterday.
The small 1 hour gap in the bar graph represents the 24th hour. The
gap is provided to ease the readability of the bar graph for the present
time. The dashed line extending horizontally from the 4 represents the
current HDOP Limit Alarm, which is set in CFG Position. The current
HDOP and VDOP values are given in the upper window.
MX Ant. Reset & CSI Reset Tools
Special tools are available in the MX500 CDU that can be used to reset
the GPS and Beacon engines in the MX antenna. Use them only in
extreme cases when the GPS or beacon receiver fails or takes too long
to lock-on. The "MX Ant Reset" softkey will clear the satellite almanac
memory of the GPS engine and reset all settings of the antenna to
factory default conditions. The "CSI Reset" softkey resets the differ-
ential beacon board.
MX Ant Reset Procedure:
This procedure will work only under Engineering level mode.
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1. Press the AUX key several times to bring up the AUX7 screen.
2. Press the EDIT key to bring up the softkeys.
3. Press the '#1' or 'NAV' button 3 times (to bring-up Eng'g level 3).
4. Highlight the "MX Ant Reset" softkey then press ENT to reset
the GPS engine (or the "CSI Reset" softkey to reset the beacon
engine).
5. Press the EDIT key to exit.
6. Press the GPS key to display the GPS or DGPS Status screen.
Engineering Mode
Version 3.0