Kongsberg cNODE MiniS - General acoustic considerations; Acoustic range; Transducer type; Acoustic noise

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Generalacoustic
considerations
Takethisinformationintoconsiderationwhendeployingthetransponders.
Acousticrange
Thetermdepthratingshouldnotbeconfusedwiththetermacousticrange.Theacoustic
rangeisdependentonmanyfactors,andsomeofthefactorsareoutsidethecontrolof
theuser.
Vesselsystem
Thedirectivityandcoverageareaforthevesselsystemisdifferent,dependingonwhich
systemyouareusing.Somesystemshavehighdirectivityandomnidirectionalcoverage,
whileothersystemshasreducedcoverageandlessdirectivity.Thetranspondershould
alwaysbewithinthecoverageconeofthevesselsystem.
Transducertype
Therearedifferenttypesoftransducersusedwiththetranspondersdependingon
operationalneeds.Anomnidirectionaltransducer,suchasTD180,coversalargearea,
buthaslessacousticpowercomparedtoafocusedtransducer,suchasTD30V .Afocused
signalgiveslessfootprint/coverage.Thevesselshouldalwaysbewithinthesignal
footprintofthetransponder.
TxPower
Theabilitytodetectsignalsdependsonthesignalstrength.Thetransmissionpowercan
beadjusted,bothforthevesselsystemandforthetransponder.
Acousticnoise
Acousticnoiseispresentatallvessels.Atgivenconditions,thenoiselevelcan
beexcessive.Avessel’spropellersandthrustersproduceacousticnoiseduring
manoeuvring,andincertaininstancesonboardmachineryandpumpsmayalsoproduce
acousticnoisewheninuse.Heavypropeller/thrusteruseaswellaswavescangenerate
airbubbles,whichcangetinfrontofthevessel’stransducerandblocktheacousticsignal.
cNODEMiniSInstructionManual