SUUNTO G9-3 - Manual (Page 14)

14
2.3.2. Navigating in the Menus
The menu items can be scrolled with the
up and down arrows located on the right side
of Suunto G9. Three menu items are displayed at the same time. The menu item that is
currently active and can thus be selected is displayed in reversed color. The indicator
bar on the left side of the display shows the active mode. To move deeper into the
hierarchy, select a menu item and press
Enter . To return one step up in the hierarchy,
press Stop/Cancel . Remember that if you just press Stop/Cancel , the changes made
in the menu are not saved. First you have to accept the changes with the Enter button.
If you want to return directly to the main display of the active mode, press either Enter
(saves the changes) or Stop/Cancel (discards the last change) for more than 2
seconds.
Suunto G9 has been designed to guide you as much as possible when you navigate
in the menus. When you perform a function, Suunto G9 often automatically returns to
the menu item that you are likely to use next.
2.4. UNDERSTANDING GPS
2.4.1. Overview
Suunto G9 uses Global Positioning System (GPS) in determining the user’s position.
GPS incorporates a set of satellites orbiting the Earth at an altitude of 20 000 km at the
speed of 4 km/s. The satellites send relatively weak radio signals at power levels
comparable to normal household light bulbs. So, the GPS reception gets disturbed
much more easily than, for example, cellular phone signal reception because the GPS
signals that reach the Earth are thousands of times weaker than cell phone signals.
However, due to the extreme sensitivity of the built-in GPS radio receiver, even the
faintest signals can be picked up.
2.4.2. Line-of-sight Needed
To ensure a good position measurement, there must be a line-of-sight connection
between the satellites and the receiver. This means that the objects or materials
between the satellites and the GPS receiver must not excessively attenuate the signal.
In practice, water-containing objects, such as people, trees or other dense vegeta-
tion, can cause problems. The signals will not penetrate rocks or buildings or any
metallic materials. However, the receiver typically works well under relatively thin
plastic, fabric or wooden covers, e.g. inside boats.