6
Your LMS-320 can record a log of the sonar signals that scroll across
the screen and save them to the MMC memory card. (These recordings
are also called sonar charts or sonar graphs.) You can replay this sonar
log in the unit using the Sonar Simulator function, or play it back on a
personal computer using our free Sonar Viewer. The viewer is available
for download from the Lowrance web site, www.lowrance.com.
You can save several different sonar log files, erase 'em and record new
ones, over and over again. The size of your sonar recordings is only
limited by the free space available on your MMC.
How LMS-320 GPS Works
You'll navigate faster and easier if you understand how the LMS-320
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 13. If you're new to GPS, read on, and
you can later impress your friends with your new-found knowledge.)
First, think of your LMS-320 as a small but powerful computer. (But
don't worry — we made the LMS-320 series easy to use, so you don't
need to be a computer expert to find your way!) The unit includes a
keypad and a screen with menus so you can tell LMS-320 what to do.
The screen also lets LMS-320 show your location on a moving map, as
well as point the way to your destination.
This gimbal-mounted unit uses an external antenna/receiver module,
which makes the whole system work something like your car radio. But
instead of your favorite dance tunes, this receiver 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 LMS-320 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 LMS-320 figures its lati-
tude and longitude, it plots that position on the moving map shown on
the screen. The whole process takes place several times a second!
The performance doesn't stop there. Stored in the permanent memory
of each LMS-320 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.
The background map is suitable for many navigation chores, but for
maximum accuracy and much more detail, you need our optional map-
making software, MapCreate 6. Some unit features — such as
