Installation manual

SimradES70
Echosoundertheory
Whenyouuseanechosoundertherearesomebasicknowledgethatyoumayndit
usefultopossess.
Topics
•Aboutbiomassonpage108
•AboutTVGgainonpage109
•Aboutdynamicrangeanddisplaypresentationonpage111
•Aboutoutputpoweronpage112
•Aboutpulsedurationonpage113
•Aboutbottomslopesonpage115
•Aboutrangeselectiononpage117
Aboutbiomass
Figure36Biomass
informationpane
ProvidedthatyouuseanES70withasplitbeam
transducer,orhaveavalidbiomasslicenseonasingle
beamtransceiver,youwillhaveaccesstotheBiomass
informationpane.
Thisbiomassvalueisanindicatortohowmuchsh
youcurrentlyhaveinthecurrentechogram,orinthe
zoomedarea.Everysingleshwillemitanecho,and
thesumofalltheseregisteredechoesarepresentedas
anumber.Smallerorganismssuchasplanktonwillalso
emitechoes,butthesearesoweakthattheywillhardly
inuenceonthetotalbiomass.
ES70recordsallthetargetsfromthesmallestplanktontothelargestwhale,andprovides
thesendingsasanumber.Forallpracticalpurposesthisnumberwillprovideyouwith
informationabouttheshabundancetoallowyoutodecideifitpaysofftostartshing.
Youmustalsoconsiderifthisnumberisaresultoflargeamountsofplanktonorbait,or
108
343539/B