Simrad ST90 - Page 353

442703/B
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Note
Withoutexternalnoisesourcesthelevelshouldnotexceed≤50dB.Ifthislevelis
exceededinanydirectionyoumustlocatethenoisesource(s).Ifthenoiseoriginateson
yourownvesselwestronglysuggestthatrelevantactionsaretakentoreducethenoise
andthusincreasetheST90performance.
Procedure
1Makesurethatyouhavesufcientwaterdepthbelowthekeelbeforeyoulower
thetransducer.
2Lowerthetransducertoitsbottomposition.
3Selectthedefaultsettings.
aOntheMainmenu,selectUserSettings.
bObservetheFactorySettingslist.
cSelectthesettingyouwishtouse.
dSelectActivateSelectedSetting.
eSelectOKtoapplyyourchangesandclosetheUserSettingsdialogbox.
4Makethefollowingpreparations.
aOntheMainmenu:
•SetRangeto1500m.
bOpentheOperationmenu.
•SetTXPowertoOff.
cOpentheActivemenu.
1SetPulseTypetoCWMedium.
2SetFrequencyto14kHz.
3SetVerticalTXSectortoNarrow.
4SetNoiseFiltertoOff.
5SettheBottomFilterThresholdtoOff.
dOpentheSetupmenu.
•SelectBITEtoopentheBITE(Built-InTestEquipment)dialogbox.
5SelectNoisetoopenthepage.
6SelectStartNoiseMeasurements.
aObservethenoisecurve.
bReadthemaximumandaveragenoisevalues.
cRepeatforselectedfrequencies.
dRecordthefrequenciesandthemeasuredvaluesintheresulttable.
Settingtowork