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442703/B
1SetPulseTypetoCWMedium.
2SetFrequencyto14kHz.
3SetVerticalTXSectortoNarrow.
4SetNoiseFiltertoOff.
5SettheBottomFilterThresholdtoOff.
dOpentheSetupmenu.
•SelectBITEtoopentheBITE(Built-InTestEquipment)dialogbox.
5SelectTransceivertoopenthepage.
Thispageprovidesagraphicpresentationofthe12transceiverboards.The
presentationreectstheirphysicallocationintheTransceiverUnit.Only
staticinformationisprovided.TheBoardInformationparametersofferkey
informationaboutthesupplypowertotheselectedtransceiverboard,aswellas
theenvironmentalconditions.
6Makesurethatallthe12transceiverboardsarefullyfunctional.
7SelectTransducertoopenthepage.
TheTransducerpagepresentsalltheelementsthatareusedintheST90transducer.
Thepresentationattemptstoorganizetheelementsinthesamemannerasinthe
physicaltransducer.Thetransceiverboardsareshownas"buttons".Selecta
transceiverboardtohighlighttheelementsthatarephysicallyconnectedtothe
board.
8SelectReceptionTesttostartanautomatictestoftheindividualtransducerelements.
ThereceptiontestvalidateseachsingleelementintheST90transducer,andreturns
thestatususingasimplecolourcoding.
•Green:Thetransducerelementisfullyoperational.
•Red:Thetransducerelementoffersreducedperformance.
•Black:Thetransducerelementisnotworking("dead").
Formoreinformation,observethetooltipprovidedforeachelementrectangle.
9Verifythatthenumberofunserviceable("dead")elementsdoesnotdegradethe
ST90performance.
Asmallnumberofunserviceabletransducerelementsareaccepted,evenfor
operationaluse.Thisisregardedas"gracefuldegradation”.
TheST90operateswith384individualchannelshandledby12transceiverboards.
Ifasinglechannelfailsduringnormaloperation,youarenotlikelytodetectit.
Evenifseveralchannelsfail,youmaynotseeit.
Thedetectionofafaultychanneldependsonthephysicallocationoftherelevant
transducerelement.Iffaultychannelsaregroupedtogetheronthetransducerface,
thismaycauseavisibledefectintheST90presentation.Iftheyarescattered,
thevisibledefectmaybealothardertosee.Inallcases,theechoesfromthe
SimradST90InstallationManual