How gps works – Lowrance electronic 5150C User Manual
Page 10
4
NOTE:
The above memory capacities refer only to the GlobalMap’s on-board
memory. The amount of GPS data you can record and save for recall
later is limited only by the number and size of MMC cards you have.
NOTICE!
The storage temperature range for your GlobalMap 5150c is from -4
degrees to +167 degrees Fahrenheit (-20 degrees to +75 degrees
Celsius). Extended storage in temperatures higher or lower than
specified will damage the liquid crystal display in your unit. This
type of damage is not covered by the warranty. For more informa-
tion, contact the factory's Customer Service Department; phone
numbers are listed on the last page of this manual.
How GPS Works
You'll navigate faster and easier if you understand how the GlobalMap
5150c scans the sky to tell you where you are on the earth – and, where
you're going. But if you already have a working understanding of GPS
receivers and the GPS navigation system, skip on ahead to Section 2,
Installation & Accessories on page 11. If you're new to GPS, read on. You
can later impress your friends with your new-found knowledge.
First, think of your unit as a small but powerful computer. But don't
worry — we made it easy to use, so you don't need to be a computer ex-
pert to find your way! The GlobalMap 5150c includes a keypad and a
screen with menus so you can tell it what to do. The screen also lets the
unit show your location on a moving map, as well as point the way to
your destination.
This gimbal-mounted GlobalMap 5150c uses an internal an-
tenna/receiver module, which makes the whole system work something
like your car radio. But instead of your favorite dance tunes, this re-
ceiver tunes in to a couple of dozen GPS satellites circling the earth. It
will also listen in to the WAAS satellites in orbit, but more about that
in the upcoming segment introducing you to GPS and WAAS.
Your unit listens to signals from as many satellites as it can "see"
above the horizon, eliminates the weakest signals, then computes its
location in relation to those satellites. Once the GlobalMap 5150c fig-
ures its latitude and longitude, it plots that position on the moving map
shown on the screen. The whole process takes place several times a sec-
ond!
The performance doesn't stop there. Stored in the permanent memory
of each unit is a basic background map of the entire world. We lock it in
here at the factory — you can't change or erase this map.