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Adjustingtheoutputpowertomatchvaryingconditions
YouarepermittedtoadjusttheoutputpowerfromtheST90.TxPowerisusedtocontrolthe
amountofpowerthatistransmittedwitheachping.
Context
MostusersoperatetheST90withTxPowersettoMaximum.Thisallowsformaximum
range,andworkswellinopenwaterswithsufcientdepth.Certainoperatingconditions
maymakeitappropriatetoadjusttheoutputpower.UseTxPowertoreducethetransmitted
acousticenergycomparedtothemaximumoutput.
Tip
Ifyouworkinshallowand/orconnedwatersyoumaynditusefultoreducetheoutput
powertoavoidreverberation.
Someofourusersclaimthatreducingtheoutputmaybeusefulifyouarelookingfor
scatteredsh.
IfyouoperateintheclosevicinityofothervesselsthatarealsousingtheST90,interference
maycauseproblems.Reducingtheoutputpowerisnotapracticalwaytodealwith
interference.Itismoreefcienttochangetheoperatingfrequency.
Toinvestigateunknownand/orunfamiliartargets,someuserpreferto"reset"theST90by
turningoffallthereceiverltersandadjusttheoutputpower .
Seaconditionsvary,sometimesdrastically.Theacousticconditionsarealsochanging.
Temperatureandsalinitylayersdifferfromonedaytothenext,andfromonepositionto
another.Itisnotpossibletoidentifysettingsthatwillprovidethebestdataatalltimes.
Procedure
1OpentheOperationmenu.
2SelectTxPower.
3Selecttherequestedoutputpower.
Selecteithersideofthebuttontochooseavalue.
Selectthemiddleofthebuttontoopenasmallmenuwiththeavailableoptions.
Relatedtopics
Choosingoperatingmodeandkeytransmitparameters,page52
SimradST90OperatorManual