Onwa KF-667 manual Suppressing Interference, Suppressing Low Level Noise

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2.12 Suppressing Interference

Interference from other acoustic equipment operating nearby or other electronic equipment on your boat may show itself on the display as shown below.

To suppress interference, do the following:

1.Select MENU1 with the [MODE ]switch.

2.Select NOISE LIMITER.

3.Press [+] or [-] to select degree of suppression desired. 3 provides the highest degree of suppression.

Interference from	Electrical interference
other sounder

Turn the noise limiter circuit off when no interference exists, otherwise weak echoes may be missed.

2.13 Suppressing Low Level Noise

Light-blue dots may appear over most of screen. This is mainly due to unclean water or noise. This noise can be suppressed by adjusting CLUTTER on the menu.

When the automatic mode is on, the clutter suppression setting is fixed at AUTO. To suppress low level noise in manual sounder operation do the following:

1.Select MENU1 with the [MODE] switch.

2.Select CLUTTER LEVEL.

3.Press [+] or [-] to select degree of suppression desired, 3 provides the highest degree of suppression.

Low level noise

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Contents Model KF-667 Safety Instructions Table of Contents Features IntroductionPage Principle of Operation System Configuration Display UnitTransducer PowerTD/Temp CONTROLS, Indications Control FunctionBrill Indications VoltageDisplay Mode Selection, Description Turning the Power On/OffAdjusting Brilliance Display mode selection200K, 50K high frequency, low frequency mode Display mode descriptionDual frequency mode Zoom mode high or low frequency Marker ZoomHow it works Adjusting GainAutomatic Operation Enabling automatic operationDisplay Range Selection Selecting Picture Advance SpeedBasic range selection Erasing Weak Echoes Range shiftingMeasuring Depth to a Fish School Scope Display Menu Operation Menu selectionMain menu description System MenuSystem menu description Menu item Description System MenuSuppressing Interference Suppressing Low Level NoiseAlarm description AlarmsSelecting Background and Echo Colors Activating/deactivating an alarm Silencing the buzzerWhite Marker Fish School Echoes Interpreting the DisplayZero Line Bottom EchoSurface Noise/Aeration Replacement of fuse MAINTENANCE,TROUBLESHOOTINGMaintenance General checkingCleaning Maintenance of the transducerBasic Troubleshooting Basic troubleshootingWater Temperature Sensor option Check Transducer CheckMenu Tree MENU1Specifications on Color Video Sounder KF-667Power Supply Index