Garmin GPSMAP 7400 Series Owner's Manual

Also see for GPSMAP 8000 Series: Owner's manual Quick start manual Instructions Owner's manual Installation instructions

Contents

Garmin GPSMAP 7400 Series Owner's Manual Manual pdf 25 page image

Advanced: Configures various sonar display and data sourcesettings (Advanced Sonar Settings).Installation: Configures the transducer (Transducer InstallationSettings).RealVü Sonar SettingsFrom a RealVü sonar view, select Menu > Sonar Setup.Point Colors: Sets a different color palette for the sonar returnpoints.Bottom Style: Sets the style for the bottom. When you are indeep water, you can set this setting to the Points andmanually set the range shallower.Bottom Colors: Sets the color scheme for the bottom.Color Key: Shows a legend of the depths the colors represent.Overlay Data: Sets the data shown on the sonar screen.Installation: Configures the transducer (Transducer InstallationSettings).LiveVü Sonar SettingsFrom a LiveVü sonar view, select Menu > Sonar Setup.Color Scheme: Sets the color palette.Trails: Sets the how long the trails appear on the screen. Thetrails show the movement of the target.Grid Overlay: Shows a grid of range lines.Noise Reject: Reduces the interference and the amount ofclutter shown on the sonar screen.Scroll History: Shows the sonar history in a traditional sonarview.Overlay Data: Sets the data shown on the sonar screen.Installation: Configures the transducer (Transducer InstallationSettings).Sonar Noise Rejection SettingsFrom a sonar view, select Menu > Sonar Setup > NoiseReject.Interference: Adjusts the sensitivity to reduce the effects ofinterference from nearby sources of noise.The lowest interference setting that achieves the desiredimprovement should be used to remove interference from thescreen. Correcting installation issues that cause noise is thebest way to eliminate interference.Color Limit: Hides part of the color palette to help eliminatefields of weak clutter.By setting the color limit to the color of the undesired returns,you can eliminate the display of undesired returns on thescreen.Smoothing: Removes noise that is not part of a normal sonarreturn, and adjusts the appearance of returns, such as thebottom.When smoothing is set to high, more of the low-level noiseremains than when using the interference control, but thenoise is more subdued because of averaging. Smoothing canremove speckle from the bottom. Smoothing and interferencework well together to eliminate low-level noise. You canadjust the interference and smoothing settings incrementallyto remove undesirable noise from the display.Surface Noise: Hides surface noise to help reduce clutter.Wider beam widths (lower frequencies) can show moretargets, but can generate more surface noise.TVG: Adjusts the time varying gain, which can reduce noise.This control is best used for situations when you want tocontrol and suppress clutter or noise near the water surface.It also allows for the display of targets near the surface thatare otherwise hidden or masked by surface noise.Sonar Appearance SettingsFrom a sonar view, select Menu > Sonar Setup > Appearance.Color: Sets the color scheme and color gain.Overlay Data: Sets the data shown on the sonar screen.A-Scope: Displays a vertical flasher along the right side of thescreen that shows instantaneously the range to targets alonga scale.Depth Line: Shows a quick-reference depth line.Edge: Highlights the strongest signal from the bottom to helpdefine the hardness or softness of the signal.Pic. Advance: Allows the sonar picture to advance faster bydrawing more than one column of data on the screen foreach column of sounder data received. This is especiallyhelpful when you are using the sounder in deep water,because the sonar signal takes longer to travel to the waterbottom and back to the transducer.The 1/1 setting draws one column of information on thescreen per sounder return. The 2/1 setting draws twocolumns of information on the screen per sounder return, andso on for the 4/1 and 8/1 settings.Sonar Alarm SettingsNOTE: Some settings require external accessories.Select Settings > Alarms > Sonar.Shallow Water: Sets an alarm to sound when the depth is lessthan the specified value.Deep Water: Sets an alarm to sound when the depth is greaterthan the specified value.Water Temp.: Sets an alarm to sound when the transducerreports a temperature that is 2°F (1.1°C) above or below thespecified temperature.Contour: Sets an alarm to sound when the transducer detects asuspended target within the specified depth from the surfaceof the water and from the bottom.Fish Alarm: Sets an alarm to sound when the transducerdetects a suspended target within the specified depth rangeand the specified color range.Advanced Sonar SettingsFrom a sonar view, select Menu > Sonar Setup > Advanced.Transmit: Stops the transducer from transmitting.Shift: Allows you to set the depth range on which the sonar isfocused. This allows you to zoom in a higher resolution in thefocused depth.When using shift, bottom tracking may not work effectively,because the sonar looks for data within the depth range ofthe focused area, which may not include the bottom. Usingshift also can impact the scroll speed, because data outsidethe depth range of the focused area is not processed, whichreduces the time required to receive and display the data.You can zoom in to the focused area, which enables you toevaluate target returns more closely at a higher resolutionthan just zooming alone.Echo Stretch: Adjusts the size of the echoes on the screen tomake it easier to see separate returns on the screen.When targets are difficult to see, echo stretch makes thetarget returns more pronounced and easier to see on thescreen. If the echo stretch value is too high, the targets blendtogether, and if the value is too low, the targets might besmall and difficult to see.You can use echo stretch and filter width together to obtainthe preferable resolution and noise reduction. With echostretch and filter width set to low, the display has the highestresolution, but is the most susceptible to noise. With echostretch set to high and filter width set to low, the display has alower resolution, but has wider targets. With echo stretch andSonar 19