Specifications

Examples
Figure14TunadetectionintheAtlanticOcean(1)
Thescreencapturefroma
Spanishvesseloperating
intheAtlanticOcean
showsscatteredYellow
ntunaveryclosetothe
surface.Theschoolwas
rstdetectedataround
1200meters.Thesonar
usesHyperbolicFM
mode.Thefrequencyis
setto28kHzwithnarrow
transmitterandreceiving
beams.
Figure15TunadetectionintheAtlanticOcean(2)
Thevesselisnow
preparingtosettheseine.
Thesonarpresentation
showsspreadY ellown
tunaclosetothevessel
onitsportside.Thesh
isspreadoutoveranarea
from200metertoalmost
600meterfromthevessel.
Echoesfromthepropeller
waterareclearlyseen
behind,andontheport
sideofthevessel.The
tiltissetatplus1degrees
asthetunaswimvery
closetothesurface.The
sonarusesHyperbolicFM
mode,andthefrequencyis
setto28kHzwithnarrow
transmitterandreceiving
beams.Totalcatchwas26
tonsoftuna.
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