ImmersionRC Duo 2400 User manual

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Duo 2400 Diversity Receiver
Twinreceiversforbestreception
Conventionalreceivershaveonebigdrawback,theyonlyallowforasingle
antennatobeconnected.Ifforsomereasonthereceptionfailsthere’sno
backupandyoulosethesignal.NotsowiththeDuo2400diversity
receiver.Withitstwinreceiversitallowsyoutohookuptwoantennas
andthemicrocontrollerinsidewillautomaticallyswitchtothereceiver
withthestrongestsignal,withoutanyswitchingnoiseorachangeinthe
imagereceived.
With‐85dBsensitivityperreceivertheDuo2400issensitive,very
sensitive.Pairedwithtwoflatpatchantennasitwillgiveyoumany
miles/kilometersofrange.ItisengineeredfromanFPV‐er’sperspective
andhencehasfeaturestomatch.It’llwarnyouwhenthereceiverbattery
runslow,orwhenswitchingantennas.Thediversityreceiverworksbest
witheithera2Sor3SLiPobatteryandthelowvoltagewarningcanbeset
accordingly,eitherautomatically,oruserconfigurable.
EquippedwithtwobufferedAVoutputsitallowsyoutoconnectyour
goggles,aswellasyourrecordingdevice,withouttheneedforY‐cablesor
asignalsplitter.OperatingtheDuo2400DiversityReceivercouldn’tbe
simpler.Afterapplyingpowerit’llbeepthenumberofLiPocellsithas
detectedandsetsthelowvoltagewarningtomatch.Selectingchannelsis
abreeze;fourchannelsaccordingtothefrequenciesusedbyAirwaveand
anothersixasusedbyLawmateareavailablewiththepressofabutton.
ImmersionRC–RealVirtuality
Twinreceiversforbestreception.
Automaticantennaswitching.
Calibratedreceiversforseamless
switchingbetweenantennas.
Dual,bufferedAVoutputs.
Automaticoruserconfigurable
lowbatteryalarm.
Canbepoweredfrom6‐12V,2Sor
3SLiPobatterypreferred.
Highbandwidthstereo‐audio.
Singlebuttonoperationfor
channelselection.
Visualindicationofselected
antenna.
TwinfemaleSMAantenna
connectors.
FMAudio/VideoModulation.
‐85dBtypicalsensitivity.
50ohmantennaimpedance.
1VppVideooutputlevel.
3VppAudiooutputLevel.
Small,lightweight,durable,
anodizedaluminumcasing.
Weight:195‐grams.
Size:82x105x26mm.
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Operating the Duo 2400 Diversity Receiver
Operatingthereceiverissimple,asasinglepush‐buttonallowsforswitchingchannelsaswellassetting
upuserconfigurablesettings.Afterapplyingpower,andprovidedthe‘auto’settingforthelowvoltage
warningisselected,it’llbeepthenumberofLiPocellsithasdetected.Sotwobeepsindicatea2SLiPo
andthelowvoltagewarningissetto6V,threebeepsindicatea3SLiPoandthelowvoltagewarningis
setto9V.
TheDuo2400DiversityReceiverhas10channelsitcantuneto;fourofthesearereservedforAirwave
audio/videotransmittersandsixforLawmateaudio/videotransmitters.It’llcyclethroughthese10
channelswitheachpressofthebutton.Airwavechannelsareindicatedwithasinglebeep,Lawmate
channelswithadoublebeep.WhenswitchingtoLawmatechannelsthere’llbealongdoublebeepfor
thefirstLawmatechannel,withsubsequentchannelshavingshortdoublebeeps.Whenswitchingto
Airwavechannelsthere’llbealongsinglebeep,withsubsequentchannelshavingashortsinglebeep.
Thelastchosenchannelisstoredandwillbetunedtoatpowerup.
Whenthelowvoltagebatteryalarmistriggeredthereceiverwillstarttobeepindicatingyouneedto
chargeorchangethebattery.Furthermoreit’llalsobeepwhentheinputvoltageistoolow,lessthan5V
ortoohigh,morethan13V.Atvoltageslessthan5Vitwillnotworkreliably,atvoltagesover13Vitwill
runhotoveralongerperiodofuse,sothisisnotrecommended.Thepowerinputisreversepolarity
protected,howeveritisgoodpracticetoalwayscheckpolaritypriortoapplyingpower.TheDuo2400
diversityreceiverpowerconnectoriscenterpinpositive,whichseemstobethenorm.
Programming the Duo 2400 Diversity Receiver
TheDuo2400DiversityReceivercanbeconfiguredtostoreuserselectedconfigurationsettings.The
selectedchannelwillalwaysbestoredsoatpowerupitdefaultstothelastselectedchannel.Other
settingsthatcanbeconfiguredare:
•Lowvoltagealarmthreshold
•RxSwitchTickenable/disable
•RxSwitchHysteresis
Programmingthesesettingsisaccomplishedbyusingthepushbutton,withfeedbackfromtheinternal
beeper,inamannersimilartothatusedbymostESCs(ElectronicSpeedControllers).
Toentertheprogrammingmenu,holddownthepushbuttonfor5secondsorlonger.Oncethe
programmingmenuhasbeenactivated,thereceiverwillstartcyclingthroughthemenuoptions,inthe
orderlisted.
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Tochangeoneoftheitems,waitforittobe‘played’,andimmediatelyafter,pressthebutton.
Thereceiverwillthen‘play’thecurrentvalue,asanumberofbeeps,andwillthenstartfromthefirst
option,andplayeachoptionuntilthelast.Selectinganoptionissimplydonebywaitingforittobe
playedandpressingthebuttonbriefly.
ForexampletochangetheRxSwitchTicksetting:
Buttonpressedfor>5seconds
DashDotDotDot‐thirdmenuitem–  pressbuttonbrieflytoentersetting
DotDot‐currentsetting
Dot‐firstavailableoption‐ TickOffpressbuttonbriefly
AtthispointtheRxSwitchTicksettinghasbeenchangedto‘TickOff’.Themodulewillnowcontinue
withthenextiteminthemenu,andcontinuetotheendofthelist.Oncetheendofthelistisreached,
thereceiverwillautomaticallyexittheprogrammingmodesignaledbytwoshortbeeps.
Beep Codes
BeepCodeMenuMenuChoices
- . LowBattVolts1–Auto(for2Sor3SLiPo)*
2–6v
3–7v
4–8v
5–9v
6–10v
7–11v
8–12v
Default:6Vfor2S,9Vfor3S
- . . LowBatt100mV1–0.0v….10–0.9v
Default:0.5v(forthresholdof9.5v)
(IgnoredinAutomode)
- . . . RxSwitchTick1–TickOff
2–TickOn*
- . . . . Hysteresis#beeps*5dB
Default:1=5dB
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Notethat*indicatesthedefaultvalue.
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Rx-change Ticks
Whenthediversityreceiver’smicrocontrollerswitchesreceivers,itissuesanaudible‘tick’.Auseful
confidence‐buildingfeaturewhenusingthereceiver,butifyoufeelthetickingbecomesannoyingyou
havetheoptionofturningitoff.
Low Battery Volts
Low Battery 100mV
Thesetwooptionscanbecombinedtosetthethresholdatwhichthelow‐voltagealarmsounds.
InAutomode(thedefault),thereceiverwillsensetheattachedbatteryvoltage,andwillsetthealarm
voltageaccordingly(6Vfor2Sand9Vfor3SLiPo).ThismodeisdesignedonlyforusewithLiPobatteries.
ForusewithNiCD,NiMh,orotherbatteries,setthealarmvoltagemanually,forexample:
9.2v setLowBattVoltsto5(9v),andLowBatt100mVto3(0.2v)
10.0v setLowBattVoltsto6(10v),andLowBatt100mVto1(0.0v)
WhenpoweringthereceiverfromLiPobatteries,itisimportanttonotethatthedischargecurveisfairly
flat,anddropsoffquicklyneartheend.Settingathresholdofaround3.0/cellisrelativelysafe.Itis
howeverhighlyrecommendedtoperforma‘dry‐run’aftersettingthevoltagewarningthresholdto
makesurethelowbatterywarningissetupcorrectly.
Ifuponconnectionofabatterypackthereceiverbeepscontinuouslythenthelowbatterywarningisset
higherthanthevoltagefromthebatterypack,soresetaccordinglyorchargethebatterypack.
Notethatregardlessofthelowbatteryalarmsettings,afixedalarmwilloccurwhenaninputvoltage
smallerthan5Vorlargerthan13Visdetected.Thissafeguardsthereceiverfrombeingusedwithinput
voltageswithwhichthecorrectoperationcannotbeguaranteed.
SafetyNote:Eventhoughthisalarmwillprovidesomeprotectionagainstlossofvideosignalduringan
FPVflight,itishighlyrecommendedtofullychargeallbatterypacksusedbeforeeachandeveryflight.
Hysteresis
Thehysteresiscontrolisusedtopreventunnecessaryreceiverswitchingwhenthedifferencebetween
theirsignal‐strengthsisminimal,forexamplewhenflyingcloseby.Thedefaultvalueshouldbe
reasonableinmostapplications.
Antenna Selection
Thediversityreceivercanbeusedwithstandard2.4GHzantennas,equippedwithamaleSMA
connector.Theideabehindtheuseoftwoantennasistopreventnullsduetomultipathinterference.A
combinationofantennascanbeusedforoptimalsignalreception.Twosmall8dBiflatpatchantennas
provideagoodcompromiseformost,buttwodifferentantennascanalsobeusedtofillinanynulls,for
examplealowgain3dBiandahighgain11dBiomni‐directionalantenna.
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