22
403825/C
Targetstrengthcalibration
summary
InordertocalibratetheEK80,areferencetarget(calibrationsphere)withknowntarget
strength(TS)isloweredintothesoundbeam.Themeasuredtargetstrengthiscompared
withtheknowntargetstrengthofthesphere,andtheEK80isadjustedaccordingly.We
stronglyrecommendthatcalibrationsurveysaredoneatregularintervals.Asaminimum,
calibrationmustbedonepriortoeachsurvey.Asummaryofthetargetstrengthcalibration
processisprovided.
Prerequisites
InordertocalibratetheEK80,thefollowingequipmentisrequired.
•Calibrationspheres:Thecalibrationspheresmustbechosentomatchtheoperational
frequenciesusedbytheEK80system.
•Wincharrangement:Thewincharrangementmustprovidethenecessarylinestolower
thesphereintothesoundbeam.
Thevesselmustbeanchoredinasuitablepositionwithsufcientdepth,calmandsheltered
water,andminimumseacurrents.
Note
Eachcalibrationspheremustbehandledwithcaretoavoidanydamagetoitssurface.
Whennotinuse,storethesphereinahouseholdsoapsolution.Allsuspensionlinesmust
beasthinandcleanaspossible.Limitknotstoaminimum,andkeepthemsmall.Even
knotshavestrongechoes!
KongsbergMaritimecansupplyavarietyofcopperandtungstencalibrationspheres
dedicatedfordifferentoperationalfrequencies.
Procedure
1PreparethevesselortestsetupforEK80calibration.
2OntheOperationmenu,setOperationtoNormal.
SimradEK80Quickstartguide