Simrad ES80 - Adjusting the Gain (Echo Sensitivity)

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406273/C
Adjustingthegain(echosensitivity)
Youcancomparethisgainsettingwiththevolumecontrolonyourcarradio.When
thegainisincreased,theechoeswillappearstronger.Weakechoeswillbeeasierto
see.However,sinceyoualsoincreasetheacousticnoiseinthereception,theES80
presentationswillalsoshowthisnoise.Toomuchgainmaytherefore"distort"the
presentation.
Context
Comparingthegainfunctionwiththevolumecontrolonyourcarradioisnotvery
accurate.Infact,thegainintheES80isconstant.TheGainfunctionisusedtoadjust
thesensitivity
.Thisdonebycontrollingtheminimumlevelofdetection.Whenyou
increasethegainlevel(morepositivenumber),youreducetheminimumlevel,andthus
increasethesensitivity.
Theechostrength(A)changeswithtime.Theminimumlevelofdetection(B)isadjusted
upordownwiththeGainfunction.IncreasingtheGainwithamorepositivenumber
reducestheminimumlevel,andthisincreasesthesensitivity.Onlyechoesoverthe
minimumlevelareshownintheechogram(C).
TheES80hasadynamicrangeof
140dB.ThismeansthattheES80
canreceivebothverystrongandvery
weakechoes.Actually,theES80will
detectechoesfromplanktontowhales,
bottomonmostdepths,andpresentthe
informationfreefromdistortion.Asa
comparison,ouroldechosounders
ES380andET100had-usinganalogue
TVG-adynamicrangecorresponding
toapproximately65dB.
Procedure
1ObservetheMainmenu.
ItsdefaultlocationisontherightsideoftheES80presentation.
SimradES80ReferenceManual