Acquisition Time Amount of time required for a GPS unit to lock onto 3 satellites to provide
a 2D fix (latitude and longitude) of present position.
Actual Sonar
Returns
With Advanced Fish I.D.™ off, Lowrance fish finders
display actual sonar returns, which show likely game fish targets as fish
arches. Actual returns also reveal important underwater detail like thermoclines,
baitfish and fish movement.
Advanced Fish
Symbol I.D.™
Also called Fish I.D., it's what many anglers say is the easiest way to identify
fish targets on their Lowrance units and is ideal for fishing shallow water.
With Fish I.D. on, it automatically interprets sonar echos and displays them as
fish symbols. The fish symbols are displayed in up to four different sizes to
match the relative size of the target echo. With Fish I.D. off, and showing
actual sonar returns, targets are displayed as fish arches.
Advanced
Signal Processing (ASP™)
Available on all Lowrance fish finders, ASP™ helps you easily spend more time
fishing, and less time adjusting sonar sensitivity. With ASP™ on, it
automatically fine-tunes your sonar settings for the clearest, most accurate
picture of the underwater world. As water conditions change, ASP™ filters out
"clutter" that interferes with sonar signals...such as boat speed and
suspended particles like algae and plankton...for the best display of fish
targets under your boat.
Alarms
Alarms are designed to alert you to certain sonar "events" by sounding
tones. With alarms, you don't need to constantly look at the display, so you
spend more time fishing. Lowrance features three main types of alarms, and all
are selectable on/off by the user.
The FISH ALARM alerts you when a fish symbol
appears on the screen, with different tones for different sizes of fish targets.
The ZONE ALARM lets you set an underwater depth
zone (e.g. 21 ft. to 53 ft.) and sounds an alarm tone when targets are detected
in that zone.
DEPTH ALARMS are triggered only by signals
returning from the bottom. Simply set the depths you want - whether Shallow
Alarm, Deep Alarm, or both - and the alarm tone will alert you when the bottom
goes shallower, or deeper, than your settings.
Backlight Selectable on/off illumination that lights both the display and keypad on
Lowrance units for enhanced screen viewing when fishing at night and in low
light.
Bearing (BRG)
The precise compass direction (in degrees) from your present position to the
next waypoint. (Readings are selectable in either degrees magnetic
or true north).
Cavitation The sudden formation and collapse of air bubbles in water due to turbulence.
If air bubbles pass over the face of the transducer, the signal from the
transducer is reflected back by the air bubbles. These reflections are
very strong and will result in noise which will interfere with
bottom, structure and fish signals, making them difficult or impossible to see.
Chart Speed The chart is the picture of the underwater world you see on the display, and
the chart speed is how fast that picture moves...or scrolls...across the screen
from right to left. This scroll speed is adjustable to help display better fish
arches...or to suit your viewing preferences when using fish symbols.
Cold Start The process of powering up a new GPS receiver for the first time and having
it search out and lock onto the satellites by itself, without the benefit of
initialization data. This procedure is slower and may require several minutes
for initial satellite acquisition.
COLORLINE™ COLORLINE™ helps separate fish and important structures on or near the bottom from the actual
bottom. Since more active-feeding fish hold close to hard bottoms and structures,
COLORLINE™ helps you find more potentially productive water quickly. By comparing
color and width you can distinguish between a hard and soft bottom.
Cross Track
Error (XTE)
Digital reading on GPS steering screens that indicates precisely how far off you
are, to the right or left of the center of the course.
Differential GPS
(DGPS)
A system devised initially by the U.S. Coast Guard that is now an international
maritime standard to improve GPS accuracy
levels to be within 10 meters. It employs a land based, fixed position, DGPS
reference receiver to first calculate any basic GPS errors (and previously
Selective Availability errors).
It then
transmits the necessary correction factors to mobile GPS receivers in the area.
DGPS does require an added beacon receiver to communicate with the
standard GPS unit.
Distance (DIS)
Distance remaining between your present position and a waypoint.
Distance To Go
(DTG)
Digital readout (selectable in miles, nautical miles, or kilometers) displayed
only when navigating to a waypoint. It simply indicates the remaining distance
from your present position to the next waypoint.
DNT/UPT Count down-timer (DNT) - Starts at a user setting and counts down to
zero. Useful for setting a time limit for travel. Count up-timer (UPT)
- Starts at zero and counts upwards. Useful as a measure of elapsed time of
travel.
Estimated
Position Error (EPE)
An estimation of the accuracy of your position that tells you how far off target
your unit might be. This calculation is based on the geometry and position of
tracked satellites, time clock offset, satellite signal quality, and more.
Estimated
Time En-Route (ETE)
An estimation of the time required to travel to a pre-selected waypoint or the
next waypoint in a route. This calculation is based on the speed and
direction of travel towards the selected waypoint.
Event Marker A graphic symbol that can be placed on the plotter display (and saved in
memory) to represent some special event or area of interest to the GPS user.
Also known as Icon.
FasTrack™
A selectable on/off feature, FasTrack™ displays flasher-style sonar returns in a
narrow vertical column at the far right of the sonar screen. Especially useful
for ice fishing or fishing at anchor, FasTrack™ is a standard feature on all
Lowrance sonar units after 2001.
Film SuperTwist Many Lowrance fish finder and GPS/mapping units use this
technology for liquid crystal displays (LCD). Film SuperTwist provides excellent
contrast and readability...in direct sunlight or with the backlight for fishing
at night or in low light...and from virtually any viewing angle. Lowrance Film
SuperTwist screens are also easy to see with polarized sunglasses.
Fish Arches With Advanced Fish I.D.™ off, Lowrance sonar units display underwater fish targets in
the shapes of "boomerangs" or fish arches. As with fish symbols, the
larger the return echo of the suspended fish target, the larger the fish arch.
To learn how fish arches are created, go to the Lowrance sonar tutorial.
FishReveal™
When viewing actual sonar returns, the unique FishReveal™ feature is what
you need to expose fish targets hiding in underwater cover -- like surface
clutter, thermoclines, and weed beds -- with 10 levels of gray tones that are
adjustable for the most revealing look in virtually any underwater environment.
FishTrack™
When using Advanced Fish I.D.™, and
with FishTrack™ on, the digital depth is displayed directly above each fish
symbol. Many Lowrance anglers find FishTrack™ helpful in making quick and precise
lure presentations to the correct depths.
Fix A measure of your receiver's position quality. A fix of 1 is poor, 9
is best
FlashGraf™
FlashGraf™ combines a scrolling sonar target graph with a digital LCD flasher
with GRAYLINE® or COLORLINE™. This allows you to view two of the most popular
ways of finding fish all in one screen. FlashGraf™ also employs the "Resize
Window" feature, which allows you to make the sonar graph or flasher "window"
wider or narrower in the split-screen display according to your preference.
Also, the "Overlay Data" feature is included to allow temp, speed, lat/long, and
more information to be displayed in the flasher "window".
FloatDucer™
This is a unique, floating transducer you can use when fishing off a bank,
shore, bridge or dock. Shaped like an odd-looking UFO, just toss the FloatDucer™
onto the water with its 50' cable connected to a fixed-mount or portable
Lowrance sonar. FloatDucer™ provides an effective wide-angle underwater coverage
area of up to 60 degrees with ASP™ on.
Global Positioning System (GPS)
The Global Positioning System (GPS) is a "constellation" of 24 well-spaced satellites that orbit the Earth
and make it possible for people with ground receivers to pinpoint their geographic location.
GPS location accuracy is within 20 meters. Location accuracy can be boosted through the use of
Wide Area Augmentation
System (WAAS) or Differential GPS (DGPS).
The GPS is owned and operated by the U.S. Department of Defense but is available for
general use around the world.
GRAYLINE®
This patented Lowrance feature helps you distinguish between hard and soft bottoms,
where the thicker the gray band, the harder the bottom. GRAYLINE® also helps
separate fish and important structures on or near the bottom from the actual
bottom. Since more active-feeding fish hold close to hard bottoms and structures, GRAYLINE® helps you find more potentially productive water quickly.
Ground Speed (GS)
Your actual speed; your speed relative to the ground being traversed in a given
amount of time.
HyperScroll™ New HyperScroll™ feature locates and displays fish targets at higher boat
speeds with increased soundings per second.
Icon A graphic symbol that can be placed on the plotter screen (and saved in
memory) to represent some special event or area of interest to the GPS user.
Also known as Event Marker.
Initialization Refers to the procedure of telling a new GPS receiver where it is, when it
is turned on for the first time. Information required for initialization
includes approximate present position in latitude/longitude coordinates, the
current local time and date.
Magnetic North Magnetic north is the location our compasses point to; it lies several
hundred miles to the south of true north, at a
location in Canada.
Map Datums Since the earth is not flat a method must be used to create a "flat
map" from a round earth. Maps and charts are based on a survey of the area
that’s covered by the map or chart. These surveys are called
"Datums". Maps that are created using different datums will show the
same latitude/longitude in slightly different locations. Different datums are
based on different mathematical models of the earth's shape and dimensions
(ELLIPSOIDS) plus an additional factor of PROJECTION.
MGRS (Military Grid
Reference System)
An alphanumeric version of a numerical UTM (Universal
Transverse Mercator) grid coordinate.
Multiplexing
Receiver GPS receiver that rotates a small number of channels to multiple satellites
in order to provide current positioning data. Typically, multiplexing receivers
require more time for satellite acquisition and lock on, and are not as accurate
as parallel channel receivers. Multiplexing receivers are also more prone to
lose satellite fix in dense woods compared to parallel
channel GPS receivers.
Noise Noise is visual "clutter" that appears on the display. It's caused
by too many undesirable signals being picked up by the fish finder (typically
from electrical sources such as trolling motors, alternators, spark plugs, radio
transmitters, etc.) Manually adjusting the sensitivity helps fine-tune the
sonar to show the most detail with the least noise. For automatic sensitivity
adjustments for the best picture possible, Advanced
Signal Processing (ASP™) is also found on all Lowrance units.
Output Power The amount of electrical energy applied to the transducer by the sonar
transmitter. Expressed in watts, typically the higher the output power the
sonar unit has, the deeper it can penetrate, and the finer the detail that can
be shown.
Parallel-Channel
Receiver GPS receiver that simultaneously tracks multiple satellites to provide the
fastest, most reliable and accurate navigational data...under the severest of
environmental conditions.
Peak-to-Peak Normally used to describe the output power of a sonar transmitter. This
value is a measurement of the total swing of an AC voltage from its peak
negative value to its peak positive value.
Pixels These are "picture elements," or little squares of color that come
together to form shapes and images on a liquid crystal display (LCD). The more
pixels per square inch, the sharper and more detailed picture you see.
Plotter Display Provides an overhead "bird’s-eye" view of your current position,
relative to the waypoints and event marker/icons
you’ve saved. A dotted-line
marks the shortest route to the chosen waypoint, and a recorded plot-trail
indicates the path you’ve taken so far.
Position Display One of the primary navigational data screens that emphasizes the present
position latitude/longitude coordinates, as well as other helpful information.
Present Position Current location on the face of the Earth, in terms of the specific
latitude/longitude coordinates, displayed in degrees/minutes/& thousandths
of a minute.
Programmable
Windows The ability to customize existing split-panel window groupings with the
specific combination of navigational data preferred.
Pulse Length The length of time a sonar unit transmits a pulse of sound into the water.
Sometimes referred to as Pulse Width.
Range Range is the depth of the water column - from the surface down - displayed
on the sonar screen. Lowrance units will automatically adjust the range to keep the
bottom (and depth shown in feet or meters) displayed in the lower part of the
screen. There's also a manual mode where anglers can select the range they want
to view from a menu of depth choices.
RMS Literally "root mean square." A DC voltage that will produce the
same heating effect (power output in Watts) as the AC voltage. For a sine wave,
the RMS value is equal to 0.707 times the peak value of an AC voltage. Example:
divide Peak-to-Peak by 2 (or in half) and multiple by 0.707 = RMS voltage.
Route Consists of two or more waypoints combined in a course of travel. It
provides the automatic capability to navigate through several waypoints, without
having to reprogram the unit after arriving at each one. Once programmed into
the GPS unit, the route provides the option of navigating forward through the
waypoints or in reverse order.
Satellite
Status Display
An information screen that shows technical data about each satellite in view.
Information includes receiver channel numbers; actual satellite I.D. numbers;
status of satellite tracking (T) or searching (S); satellite elevations and
azimuths; signal-to-noise ratios (higher the number, the better); and dilution
of precision ratings (GDOP is most important; smaller the number, the better).
Savable Plot
Trails The capability to save the actual trail created on the plotter display,
thereby enabling the GPS user to either backtrack the course immediately...or
retrace the trip at a later time.
Selective
Availability (S/A)
The system used by the U.S. Department of Defense prior to May 1, 2000 to intentionally degrade the
accuracy of satellite GPS signals being transmitted to civilian GPS receivers.
Until recently, all brands of civilian GPS receivers were equally affected by S/A. With random
S/A on, the government had agreed that civilian GPS accuracy levels would
consistently be 100 meters or less, 95% of the time. Now that S/A restrictions
have been lifted, accuracy levels have improved to 20 meters or less.
Sensitivity This is a manual adjustment that allows users to fine-tune the fish finder
to see the most underwater detail with the least visual noise.
For anglers who'd rather spend more time fishing than adjusting, Advanced
Signal Processing (ASP™) does this automatically, and is a feature of all Lowrance
sonar units.
Skimmer®
Available in a variety of operating frequencies, Skimmer transducers feature a
low profile for high-speed performance...even up to 70 mph! The patented design
helps prevent cavitation and other interference that
affects sonar performance. Finely tuned to provide exceptional echo sounding,
transom-mounted models feature a kick-up bracket for protection against impact
with debris and obstructions.
Speed/Temp Using special sensors, Lowrance units can digitally display surface water
temperature, boat speed and distance log (odometer) in addition to showing the
depth range. Serious anglers, especially tournament pros, use speed and
temperature information as aids in their fishing strategies. Note: displaying
speed is used solely for trolling purposes, and does not work at
"top-end" boat speeds.
Speed Over
Ground (SOG)
Digital reading that indicates your current ground speed. (Selectable in
miles-per-hour, knots, or kilometers-per-hour)
Steering Screen Shows a graphic, "highway view" of the GPS user’s Course
Over Ground. Provides helpful instructions as to how far off-course...which
direction to steer, right or left, to make corrections...and displays related
nav-data pertaining to the waypoint.
Straight
Line Navigation The standard method of navigation used by recreational GPS products. When
commanded to navigate to a waypoint, the unit draws a straight, dotted line from
the present position to the selected waypoint. It’s the shortest, most direct
route to the destination. Caution: Straight line navigation does not take into
account any obstacles in the path; interim waypoints may be required to navigate
safely around obstacles
Structure Structure is basically all solid objects rising from the bottom of a lake or
river that isn't part of the actual bottom...like sunken trees, brush and rock
piles...which creates habitats, feeding grounds and cover for game fish. For
locating and separating close-holding fish from structure, GRAYLINE®
is the preferred choice of more anglers.
Thermocline These are areas underwater where warmer layers of water meet cooler layers,
and where fish are often active. Generally, baitfish hang just above the
thermocline, while larger game fish are found suspended in or just below it.
Lowrance units will display thermoclines when used in the manual mode, showing
actual sonar returns, and with the sensitivity set correctly.
Time To Go (TTG)
Digital reading showing the time remaining from your current position to the
next waypoint. This function takes into account your Distance
To Go (DTG), and your Velocity Made Good (VMG)
to give you as closely as possible the amount of time left to reach your
waypoint. Displayed in hours, minutes, and seconds, it will continue counting
down until waypoint is reached.
Transducer The part of the fish finder that functions like an antenna to send out sonar
signals (sound waves) and receive return echoes that are displayed as pictures
on the sonar screen. Lowrance transducers can be attached to the transom
or inside the hull of a boat, or even to a trolling motor using a special
mounting.
True North True north is the top of the world, where all lines of longitude converge;
not to be confused with magnetic north.
UTC Coordinated Universal Time. Time at the prime meridian at Greenwich,
England. Formerly known as GMT.
UTM (Universal Transverse
Mercator)
Universal Transverse Mercator (UTM) coordinates define two-dimensional,
horizontal positions. Each ZONE in UTM is given a number from 00 to 59 starting
at the International Date Line and progressing east. UTM also divides each zone
horizontally as well. These divisions start at the equator and are 8 degrees
wide. The first half of the alphabet is used for the Southern Hemisphere while
the second half is used for the Northern Hemisphere. Thus a point just above the
hemisphere would be the letter N proceeding to the letter X at the north pole,
while just below it would be an M and proceeding backwards to the letter C at
the south pole.
Velocity Made
Good (VMG)
Digital speed reading, similar to Speed Over Ground
(SOG), that compensates for progress being made toward a waypoint. For
example, when traveling directly on course toward a waypoint, the SOG and VMG
readings may match. However, when traveling off course, the VMG reading will
typically be slower than the SOG. VMG is a true indication of the speed being
made to the selected waypoint.
Waypoint Location, spot, or destination (latitude/longitude) that can be stored in
memory to be recalled and used at a later time for navigation purposes. Simply
think of it as an electronic address.
WAAS - (Wide Area Augmentation System) A satellite navigation system designed by the U.S. Federal Aviation
Administration (FAA) to boost the accuracy of GPS satellite navigation. Improvements in
accuracy are approximated to be within 7 meters. Note:
Currently, WAAS is not fully implemented. It was created for aviation
applications. It uses geostationary satellites over the equator, which makes
WAAS signals easily blocked in North America by terrain obstructions. Users may experience
temporary loss of WAAS support, especially in wooded areas.
Zoom With zoom, you can enlarge the Lowrance sonar or GPS map display for a
closer look at small detail and fish target signals. In the sonar automatic zoom
mode, the bottom is constantly tracked and displayed in the lower portion of the
screen (also called "zoom bottom track"). In the manual zoom mode, you
can create a zoom "window" of any size, and move it anywhere up or
down in the sonar water column...it doesn't remain locked on to display the
bottom.
