•Usinganon-widebandVHFantennaoptimizedonlyforVHFradiofrequenciesmaycause
transmissionsfromtheAIStransceivertobereflectedbackintotheAIS700
,duetothepoor
impedancematchoftheantennaandAIStransceiverfrequencies.Althoughthiswillnotdamage
theAIS700(becauseAISclassBtransmissionsareofsubstantiallylowerpowerthanVHF
transmissions),itcouldresultintheAIS700triggeringasystemVSWRalarm.
•NewVHFantennasaresoldwithafixedcablelength.Thecablelengthpartlydeterminesthe
antennaperformance,andthereforecuttingthecableofanantennacanaffectitsperformance
andresultinahighVSWRratioandlimitedreception.
RecommendedspecificationsforaVHFantennasuitableforconnectingtotheAISunit:
Frequencyband
156.025MHzto162.025MHz
V SWR(VoltageStandingWaveRatio)
shouldnotexceed2:1,acrosstheentire
frequencyrange
Impedance
50Ohmwideband
Gain
3dBiMax
ConnectortypePL-259
6.3V SWRAlarmtroubleshooting
IfyouexperienceregularVSWRalarmstrythetroubleshootingguidancebelow.
P ossiblecausesPossiblesolutions
Incorrectantennainuse .
Checkthatyourantennameetstherequired
VHFantennaspecificationthatcanbefoundin
theproductdocumentation.
Antennashortoropencircuit.
Checkantennaforshortoropencircuit,repair
orreplaceasnecessary
.
ProductrunninganolderversionofsoftwareSoftwareversion1.09includedImprovementsto
Antennafaultdetection(V SWRalarm).
6.4Dataconflictsanddataloops
T oavoidpotentialdataconflictsanddataloops,productsshouldnotbeconnectedtothesame
deviceusingmorethanonenetworkprotocol.
Important:
•DoNO TconnecttoanMFDorVHFradiousingNMEA0183andSea Talkng®/NMEA2000
connectionsatthesametime.
•DoNOTconnecttoaPCusingNMEA0183andUSBconnectionsatthesametime.
•IfyouareconnectingtoaVHFRadiothathasbuilt-inAIS,youmustfirstdisabletheVHFRadio’s
AISfunction,beforeconnectingittotheAISunit(orthesamedatanetwork).Refertoyour
Radio’sdocumentationfordetailsondisablingtheVHFRadio’sAISfunction.
6.5LEDS tatusindicator
TheLEDstatusindicatoronthetransceiverprovidesanindicationofproductstatus.
LEDColorS tatus
Green
Transceiverispoweredupandoperatingnormally.
AmberTransceiverisnottransmitting.
•Waitatleast30minutestocheckthata‘Quiettime’has
notbeenrequestedbythelocalauthority.
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