Magellan GPS PROMARK X, User Manual

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Troubleshooting & Operating Tips ProMARK X
8-12
Poor environments include areas of dense foliage or dense construction
(even a one-story building can block signals when the visible satellites have
low elevations). It also includes locations with a limited view of the sky, such
as a site at the bottom of a deep canyon.
Often, the effects of a poor signal environment can be alleviated by adequate
planning. For example, be sure the antenna has as clear a view of the sky as
possible. Use SETUP to be sure the mask angle adequately reflects the
physical conditions at the location. Setting the unit to use 2D instead of 3D
or AUTO will often help since the unit will use a different satellite set for a
2D solution than for a 3D solution. Also, check Sat Schedule to be sure that
you are using the unit when as many satellites as possible are visible to your
location.
A weak signal environment may also cause multipath problems. Multipath
errors occur when the unit receives a mix of direct and indirect signals.
Indirect signals are usually caused when atmospheric conditions affect the
signals emitted by satellites with low elevations. They may also be caused by
highly reflective structures in the vicinity of the receiver. Multipath errors are
characterized by sudden shifts and variations in the SQ of collected data.
Some multipath problems can be eliminated by using satellites with high
elevations. A multipath-resistant antenna is available as part of the Submeter
Kit.
Insufficient Number of Satellites . The ProMARK X checks its almanac
before beginning to search for satellites. The receiver will not turn on if the
almanac indicates that not enough satellites are within view to establish a
position fix.
This message appears when the
almanac indicates that not enough
satellites are in view to take a fix.
The receiver remains off.
If you are operating with the Battery Saver on, the unit shuts itself off if it
cannot locate enough satellites for a fix.
This message appears when the
unit is set to 3D operation, and not
enough satellites are available for
a 3D fix. Try 2D, which requires
fewer satellites.
NOT ENOUGH
SATS UP
NOT ENOUGH
SATS UP
TRY 2D