Echosoundertheory
Relatedtopics
•Adjustingthepulseduration(length)onpage72
Rangeselection
Foreveryfrequency(channel)youwishtopresentontheechosounderdisplay,youare
providedwithtwoechograms.
Figure12Rangeselection
AUpperechogram(surface
related)
BLowerechogram(bottom
related)
CScopeviewforupperechogram
DScopeviewforlowerechogram
Normally,theupperechogramwill
showtheentiredepthrangefrom
theseasurfaceanddowntothe
bottom,whilethelowerechogram
showsabottomexpansion.Thisis
amagnicationoftheareajustabove
andbelowthebottom.
Youarefreetochooseany
presentationyouwantinanyofthe
echograms.
Todothis,opentheEchogramdialog
ontheActivemenu.
Upperechogram:Pelagicorsurfacerelated
Whenyouneedtoestablishaverticaldepthrange,whynotlettheechosounderchoose
itforyou.Onthemainmenu,setRangetoAuto.
Youcanalsodeneyourowndepthrange.Toestablishadepthrangefromthesurface
anddowntothebottom,setRangetoasuitabledepth,andStartRangeto0(zero)meters.
Aphasedareamayalsobeestablished.Thisisusedwhenyouwishtoconcentrateon
acertainandlimiteddepthrangeIfyouforexamplendsaschoolofsh150meters
belowthesurface,youcansetuptheechosoundertoshowthisschoolwithoutalso
providedinformationfromthewatercolumnoverandunderit.Tosetthisup,setStart
Rangetoafewmetersabovetheschool,andRangetoafewmetersbelowit.
Ifyouarebotheredbyinterferencefromasonarusingthesameoperationalfrequency,
trytosetStartRangeto10to20meters.Youwillthenavoidthenoisewhenboth
systemstransmitsimultaneously.
343539/C
129
Comments to this Manuals