Raymarine c97 - Radar Context Menu; Radar Range and Image Quality

16.5Radarcontextmenu
Theradarapplicationincludesacontextmenuwhich
providespositionaldataandmenuitems.
Thecontextmenuprovidesthefollowingpositional
dataofthecursor’slocationinrelationtoyourvessel:
•Latitude
•Longitude
•Range
•Bearing
Thecontextmenualsoprovidethefollowingmenu
items:
•AcquireTarget
•PlaceWaypoint
•PlaceVRM/EBL
Accessingthecontextmenu
1.Non-touchscreenandHybridT ouchdisplays:
i.Movethecursorovertheareaorobjectand
pressingtheOkbutton.
2.HybridT ouchandTouchonlydisplays:
i.Selectandholdonanareaorobject,or
ii.WiththeChartCall-outdisplayedselectthe
Call-outbox.
16.6Radarrangeandimagequality
Radarimagequality
Anumberoffactorscanaffectthequalityofaradar
image,includingechoes,seaclutter,andother
interference.
Notallradarechoesareproducedbyvalidtargets.
Spuriousormissingechoesmaybecausedby:
•Sidelobes.
•Indirectechoes.
•Multipleechoes.
•Blindsectors.
•Sea,rain,orsnowclutter.
•Interference.
Throughobservation,practice,andexperience,you
cangenerallydetecttheseconditionsveryquickly
andusetheradarcontrolstominimizethem.
SideLobes
Sidelobepatternsareproducedbysmallamountsof
energyfromthetransmittedpulsesthatareradiated
outsidethenarrowmainbeam.Theeffectsofside
lobesaremostnoticeablewithtargetsatshort
ranges(normallybelow3nm),andinparticularwith
largerobjects.Sidelobeechoesformeitherarcson
theradarscreensimilartorangerings,oraseriesof
echoesformingabrokenarc.
D16 3 8-5
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ItemDescription
1Mainlobe
2
Sidelobes
3Antenna
4Arc
5
Trueecho
6
Sideechoes
IndirectEchoes
Thereareseveraltypesofindirectechoesorghost
images.Thesesometimeshavetheappearanceof
trueechoes,butingeneraltheyareintermittentand
poorlydened.
Radarapplication
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