Garmin eTrex User Manual

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Can I use the eTrex indoors?
No. The DEMO mode is available, but we suggest that only dealers 
use it.
Do I need to subscribe to a service to use the eTrex?
No. The GPS satellites are owned by the United States Department 
of Defense (DoD) and have been funded by U.S. taxpayers’ dollars.  
Reception of GPS satellite signals is free to everyone.
Does the eTrex work anywhere in the world and in any 
weather?
Yes.
How accurate is a GARMIN GPS?
The eTrex is accurate to within 15 meters without the DoD-imposed 
Selective Availability (S/A). Using differential techniques, the eTrex 
can be as accurate as 1-5 meters.  The eTrex is accurate to within 
100 meters under S/A. 
Another factor that will effect the accuracy of the GPS receiver is 
the geometry of the satellites in view of the GPS receiver.  A poor 
geometry situation can provide less accurate position readings, and 
this especially applies to GPS altitude measurements. The altitude 
reading on the GPS unit can vary by +/- 450 ft. depending on the 
level of degradation being imposed under S/A. It is not uncommon 
to see the altitude continuously drift up and down when S/A is 
being imposed. 
Why can’t I see the display in the daylight?
Adjust the contrast (see page 9).  
Why can’t I interface my computer with the eTrex?
Make sure that you have the correct INPUT/OUTPUT format 
selected on your eTrex.  
What Grid Formats does the eTrex Support?
hddd.dddddo (degrees, decimal degrees)
hdddomm.mm (degrees, minutes, decimal minutes)
hdddomm’ss.s (degrees, minutes, seconds, decimal seconds)
British Grid
Dutch Grid
Appendices
Appendix G
FAQs
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