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1202VLZ4
1202VLZ4
Unbalanced RCA Connector
RCA-typeplugs(alsoknownasphonoplugs)
andjacksareoftenusedinhomestereoandvideo
equipmentandinmanyotherapplications.RCAplugs
areunbalanced.Connectthesignaltothecenterpost
andtheground(earth)orshieldtothesurrounding
“basket.”BesurethecablesarewiredperAES(Audio
EngineeringSociety)standards:
Unbalanced RCA Connector
Sleeve–Shield(Ground)
Tip–Positive(+orhot)
Unbalancing a Line
Inmoststudio,stageandsoundreinforcementsitu-
ations,thereisacombinationofbalancedandunbal-
ancedinputsandoutputsonthevariouspiecesof
equipment.Thisusuallywillnotbeaprobleminmaking
connections.
• Whenconnectingabalancedoutputtoan
unbalancedinput,besurethesignalhigh(hot)
connectionsarewiredtoeachother,andthat
thebalancedsignallow(cold)goestothe
ground(earth)connectionattheunbalanced
input.Inmostcases,thebalancedground
(earth)willalsobeconnectedtotheground
(earth)attheunbalancedinput.Ifthereare
ground-loopproblems,thisconnectionmaybe
leftdisconnectedatthebalancedend.
• Whenconnectinganunbalancedoutputtoa
balancedinput,besurethatthesignalhigh
(hot)connectionsarewiredtoeachother.The
unbalancedground(earth)connectionshould
bewiredtothelow(cold)andtheground
(earth)connectionsofthebalancedinput.If
thereareground-loopproblems,tryconnecting
theunbalancedground(earth)connectiononly
totheinputlow(cold)connection,andleaving
theinputground(earth)connectiondiscon-
nected.
• Insomecases,youwillhavetomakeupspecial
adapterstointerconnectyourequipment.For
example,youmayneedabalancedXLRfemale
connectedtoanunbalanced1⁄4"TSphone
plug.
TIPSLEEVETIPSLEEVE
Unbalanced RCA Connector
TRS Send/Receive Insert Jacks
Single-jackinsertsarethree-conductor,TRS-type1⁄4"
phone.Theyareunbalanced,buthaveboththemixer
output(send)andthemixerinput(return)signalsin
oneconnector.Seetheillsutrationbelow.
Thesleeveisthecommonground(earth)forboth
signals.Thesendfromthemixertotheexternalunitis
carriedonthetip,andthereturnfromtheunittothe
mixerisonthering.
Special Connections
Thebalanced-to-unbalancedconnectionhasbeenan-
ticipatedinthewiringof1202VLZ4jacks.A1⁄4"TSplug
insertedintoa1⁄4"TRSbalancedinput,forexample,
willautomaticallyunbalancetheinputandmakeallthe
rightconnections.Conversely,a1⁄4"TRSpluginserted
intoa1⁄4"unbalancedinputwillautomaticallytiethe
ring(loworcold)toground(earth).
Using the Send Only on an Insert Jack
IfyouinsertaTS(mono)1⁄4"plugonlypartially(to
therstclick)intoaVLZ4insertjack,theplugwillnot
activatethejackswitchandwillnotopentheinsert
loopinthecircuit(therebyallowingthechannelsignal
tocontinueonitsmerrywaythroughthemixer).
Thisallowsyoutotapoutthechannelorbussignal
withoutinterruptingnormaloperation.
Ifyoupushthe1⁄4"TSplugintothesecondclick,
youwillopenthejackswitchandcreateadirectout,
whichdoesinterruptthesignalinthatchannel.Seethe
illustrationonthenextpage.
Unbalanced 1/4" Insert Connectors
tip
This plug connects to one of the
mixer’s Channel Insert jacks.
ring
tip
ring
sleeve
SEND to processor
RETURN from processor
(TRS plug)