Furuno FR-8051 manual Watch Alarm, Echo Average, Silencing the aural alarm

Page 38

Guard zone to set

A D A

B C

Set cursor on point A (or B) and

(1)press GUARD ALARM.

(or GUARD2)

GUARD1

IN

(or OUT)

Press

GUARD

ALARM.

(4)

Guard zone

(or GUARD2)

GUARD1

SET

(2)

(or GUARD2)

GUARD1

SET

Set cursor on point C (or D).

(3)

1.29 Watch Alarm

The watch alarm works like an alarm clock, sounding an aural alarm and blinking a visual indication "T ALM" at the predetermined time interval. When the alarm sounds, you can silence it by pressing the AUDIO OFF key.

You can select time interval (3 min, 6 min, 12 min, 15 min, or 20 min) on the TIME ALM menu.

1)

Press the MENU key.

2)

Select the TIME ALM menu.

3)

Press the ENTER/SELECT key.

4)

Select TIME ALM and press the ENTER/SE-

 

LECT key.

Figure 1-25 How to set the guard alarm

Note: When the radar range is less than one half of the guard zone range, the guard zone disap- pears and the indication of active guard zone (GUARD1 or GUARD2) appears in highlighted video. If this happens, raise the range to re-display the guard zone.

Silencing the aural alarm

When a target violates the guard zone, the target flashes and the aural alarm sounds. You can si- lence the aural alarm by pressing the GUARD ALARM key. When this is done, ACK replaces IN (or OUT). This means the aural alarm is tem- porarily deactivated; but, the target still flashes. Press the key again to reactivate the alarm.

Canceling the guard zone and guard alarm

Press and hold down the GUARD ALARM key about two seconds until the guard zone disap- pears.

5)

Select time interval (or OFF).

6)

Press the ENTER/SELECT key.

7)

Press the MENU key.

1.30 Echo Average

The echo average feature effectively suppresses sea clutter and other random noise. Echoes re- ceived from stable targets such as ships (if not moving at high speeds) appear on the screen at almost the same position every rotation of the antenna. On the other hand, unstable echoes such as sea clutter appear at random positions.

To distinguish real target echoes from sea clutter, this radar performs scan-to-scan correlation. Cor- relation is made by storing and averaging echo signals over successive picture frames. If an echo is solid and stable, it is shown in its normal in- tensity. Sea clutter is averaged over successive scans and reduced in brightness. This makes it easier to discriminate real targets from sea clut- ter.

To properly use the echo average feature, first properly suppress sea clutter with the A/C SEA control and then select echo average function as follows;

How to turn on echo averaging

1)Press the MENU key.

2)Select the ECHO SIG menu.

1 – 23

Image 38
Contents Marine Radar First Edition NOV Safety Information Do not diassemble or modify the equipment Radio Frequency Radation Hazard IiiUse the correct fuse Table of Contents Maintenance Vii Features Word to FR-8051/8111/8251 OwnersForeword Configuration of FR-8051/8111/8251 Transceiver Module SpecificationsAntenna Unit Environmental Conditions Power Supply and Power ConsumptionDisplay Unit OthersXii Equipment ListsStandard Set Name Type Qty RemarksXiii Optional EquipmentSpare Parts Name Type Code No RemarksFunction Type Categorization by SpecificationXiv Operation Control DescriptionDisplay Indications 25 NMDisplay indications lower part Transmitting, Stand-by Turning the Radar On/OffSelecting Range Presentation mode Description Representative display Presentation ModeSelecting presentation mode Presentation mode DescriptionChanging pages on the Initial menu Menu OverviewBasic menu operation Menu tree MK Erase erase all fixed marksInitial Tune SET AUTO, Manu SPD Mode MAN, LOG, NAV Adjusting Picture Brilliance Tuning the ReceiverAdjusting Sensitivity Selecting tuning modeSuppressing Sea Clutter Adjusting Brilliance of Control Panel and MarkersAdjusting Range Ring Brilliance Automatic anti-clutter controlMeasuring the Range Suppressing Rain ClutterHeading and North Markers Measuring range by the range ringsMeasuring Bearing Canceling the cursor offset Collision Assessment by Measuring Range Offset EBLIndex Lines Off-centering the PictureFunction key ZoomInscribing Marks on the Display Automatic speed input Own Ship SpeedTurning on a function Echo Trails Ship’s GraphicInterference Rejector Manual speed inputTrail time Canceling echo trailStarting echo trail Trail referencePlotting a target Electronic Plotting E-plotTrail brilliance True or relative vector Canceling target plottingTarget data Vector timeSelecting guard zone type Setting a Guard Alarm ZoneSetting a guard zone Activating the guard zonesCanceling the guard zone and guard alarm Watch AlarmSilencing the aural alarm How to turn on echo averagingSuppressing Second-Trace Echoes 26 Echo averageNoise Rejection Presetting pulselengthEcho Stretch Selecting PulselengthSelecting pulselength set to use Waypoint DisplayOutputting Cursor Position TLL data Sector Blanking Alarm Output Signal On/OffSelecting Unit of Range Measurement, Bearing Reference Radar Picture, Target Properties and Radar Pulse Range ResolutionRadar Observation Indirect echoes Bearing ResolutionFalse Echoes Multiple echoesMinimum range Minimum and Maximum RangesSide-lobe echoes Blind and shadow sectorsLocating a Ship or Survival Craft in Distress by Sart Gain Maintenance When Working on the Antenna UnitInterval Check point Check and measures Remarks Part Type Life expectancy RemarksProblem Remedy TroubleshootingSimple Troubleshooting Problem Check point and probable Remedy Cause Advanced-level TroubleshootingServiceman qualification Problem Check point and probable Remedy Cause Problem Check point and probable Remedy Cause Diagnostic Test Diagnostic test, test patternLocation of Parts Antenna UnitRF Transceiver Unit Modulator TriggerRF transceiver unit FR-8051/8111 Display Unit common to all models Display unit, top viewDisplay unit, right side view Transmitter Receiver Performance Performance MonitorOperating a performance monitor Display Meaning Transmitter normal Receiver normalFluxgate Heading Sensor C-2000 Auto Plotter ARP-15Video Plotter RP-15 Page