A Combination Fishfinder is a device that
employs fishfinder
characteristics typically with a
chartplotter,
gps,
radar,
loud hailer, Marine
VHF Radio. These devices
usually help save vessel dashboard space and often display complementary data on
a common dislay.
A fishfinder is a type of
fathometer, both being specialized types
of
echo sounding systems, a type of Active
SONAR.
('Sounding' is the measurement of water depth, a historical nautical term of
very long usage.) The fishfinder uses active sonar to detect fish and 'the
bottom' and displays them on a graphical display device, generally a
LCD
or
CRT screen.
The distinction is in their main purpose and hence in the features given the
system. Both work the same way, and use similar frequencies, and, display type
permitting, both can show fish and the bottom. Thus today, both have merged,
especially with the advent of computer interfaced multipurpose fishfinders
combining
GPS
technology, digital chart-plotting, perhaps
RADAR and
electronic compass displays in the same affordable sporting unit.