Garmin GPS 75 - Manual (Page 15)

3-1
CHAPTER 3
BASIC OPERATION
3.1 POWER ON
After you turn your GPS 75 on, it will conduct a series of self tests and
display the following notice:
Following completion of the tests, the Satellite Bar Graph Page (see
Section 3.2) will be displayed, and the GPS 75 will begin acquiring
satellites.
After a position is found (and if no keys have been pressed), the Position
Page (see Section 3.3) will be displayed, and the unit is ready for normal
operation.
When four or more satellites with good geometry are available, the GPS
75 will automatically operate in the 3D mode in which latitude, longitude,
and altitude are computed. If only three satellites are available, the unit
will operate in 2D mode in which only latitude and longitude are
computed. When operating in the 2D mode, the unit will use the last
computed altitude or your last entered altitude. (Section 3.3 describes
how you may enter the altitude.)
Your GPS 75 will automatically update satellite orbital data as it
operates. If you have not operated your unit for a period of six months
or longer, it will take approximately 15 minutes to search the sky and
collect new orbital data. You will be informed when your unit is
searching the sky with the message “Searching the Sky.” Once satellite
orbital data is collected, it will be stored in memory. The memory is
maintained by an internal battery, therefore the data will not be lost
when you turn your GPS 75 off.