McIntosh MR80 User manual

ReadingTime:32Minutes
Price:$2.00
THEMclNTOSHMR80DIGITALFMTUNER

VARIOUSREGULATORYAGENCIESREQUIRETHATWEBRINGTHEFOLLOWING
INFORMATIONTOYOURATTENTION.PLEASEREADITCAREFULLY.
WARNING:TOPREVENTFIREORSHOCK
HAZARD,DONOTEXPOSETHISUNITTO
RAINORMOISTURE.
TheMclntoshyouhavepurchasedisa Model
MR80.Ithasa serialnumberlocatedontherear
panelofthechassis.Recordthatserialnumber
here:
SerialNumber
Themodel,serialnumberandpurchasedateare
importanttoyouforanyfutureservice.Recordthe
purchasedatehere:
Purchasedate
Uponapplication,MclntoshLaboratoryprovidesa
Three-YearServiceContract.YourMclntoshauthor-
izedserviceagencycanexpediterepairswhenyou
providetheServiceContractwiththeinstrumentfor
repair.Toassist,recordyourServiceContract
numberhere:
ServiceContractNumber

YourMR80DigitalFMTuner
cangiveyoumanyyearsof
satisfactoryperformance.Ifyou
haveanyquestions,pleasecontact:
CUSTOMERSERVICE
MclntoshLaboratoryInc.
2ChambersStreet
Binghamton,NewYork13903-9990
Phone:[phone]
TakeAdvantageof3 years
ofContractService...
FillintheApplicationNOW.
Contents
SERVICECONTRACTINFORMATION. ..1
INSTALLATION..2
HOWTOCONNECTAND
BACKPANELINFORMATION...4
FRONTPANELINFORMATION
ANDUSEOFCONTROLS.. .6
TOPPANELINFORMATION
ANDSECONDARYCONTROLS...8
PERFORMANCELIMITS. . .9
PERFORMANCECHARTS.-10
TECHNICALDESCRIPTION.14
BLOCKDIAGRAM..20
MclNTOSHTHREEYEARSERVICECONTRACT
AnapplicationforA THREEYEARSERVICECONTRACTisincludedwiththismanual.
Thetermsofthecontractare:
1.Mclntoshwillprovideallparts,materials
andlaborneededtoreturnthemeasured
performanceoftheinstrumenttothe
originalperformancelimits.TheSER-
VICECONTRACTdoesnotcoverany
shippingcoststoandfromtheauthoriz-
edserviceagencyorthefactory.
2.AnyMclntoshauthorizedserviceagency
willrepairMclntoshinstrumentsatnor-
malservicerates.Toreceiveservice
underthetermsoftheSERVICECON-
TRACT,theSERVICECONTRACTCER-
TIFICATEmustbepresentedwhenthe
instrumentistakentotheserviceagency.
3.Alwayshaveservicedonebya
Mclntoshauthorizedserviceagency.If
theinstrumentismodifiedordamaged
asa resultofunauthorizedrepair,the
SERVICECONTRACTwillbecancelled.
Damagebyimproperuseormishandl-
ingisnotcoveredbytheSERVICE
CONTRACT.
4.TheSERVICECONTRACTisissuedto
youastheoriginalpurchaser.Topro-
tectyoufrommisrepresentation,this
contractcannotbetransferredtoa se-
condowner.
5.ToreceivetheSERVICECONTRACT,
yourpurchasemustbemadefroma
Mclntoshfranchiseddealer.
6.Yourcompletelyfilledinapplicationfor
theSERVICECONTRACTmustbepost-
markedwithin30daysofthedateof
purchaseoftheinstrument.
7.ToreceivetheSERVICECONTRACT,all
informationontheapplicationmustbe
filledin.TheSERVICECONTRACTwill
beissuedwhenthecompletelyfilledin
applicationisreceivedbyMclntosh
LaboratoryIncorporatedinBinghamton,
NewYork.
8.UnitsinoperationoutsidetheUnited
StatesandCanadaarenotcoveredby
theMclntoshFactoryServiceContract,
irrespectiveoftheplaceofpurchase.
Norareunitsacquiredoutsidethe
U.S.A.andCanada,thepurchasersof
whichshouldconsultwiththeirdealer
toascertainwhat,ifany,servicecon-
tractorwarrantymaybeavailablelocally.
Copyright1980© byMclntoshLaboratoryInc.
1

HowtoConnectand
BackPanelInformation
Refertopage5.
AUDIOOUTPUTS
UsetheFIXEDOUTPUTjacksontherearpanelto
feedprogramtoa stereocontrolpreamplifieror
otherequipmentwhichhasitsownvolumecontrol.
ThefrontpanelVOLUMEcontroldoesnotaffectthe
loudnessofthetunerattheFIXEDOUTPUTjacks.
Theoutputlevelisa nominal1 voltfor100%FM
modulation.
UsetheVARIABLEOUTPUTjackstoconnectto
equipmentsuchasa poweramplifierora tape
recorderwherecontrolofthevolumeatthetuneris
desired.TheoutputattheVARIABLEOUTPUTjacks
isa nominal2.5voltsfor100%FMmodulation.
Thereisnodifferenceinthesignalqualityateither
pairofoutputjacks.
BothpairsofOUTPUTjacksmaybeusedsimul-
taneously.Theoutputimpedanceatbothoutputsis
verylowsothatlongaudiocablescanbeused
withouta lossofhighfrequenciesduetocable
capacity.
RFINPUTS—ANTENNACONNECTIONS
Twooffourdifferentantennasystemscanbe
usedwithyourMR80.1)anoutdoorFMantenna,2)
anallchannel(UHF-VHF-FM)antenna,3)a cablein-
putfromyourlocalcablecompany,or4)theindoor
dipolesuppliedwiththeMR80.A switchisprovided
onthetoplevelsetpaneltoselectbetweentwoof
thefoursystemsmentioned.
Anoutdoorantennaisrecommendedforoptimum
performanceinallareas.Infringeareas,bestresults
willbeobtainedwitha highlydirectionalFMan-
tennausedinconnectionwitha rotator.Rotatethe
antennauntilthebestreceptionisobtained.Con-
necta 300ohmoutdoorantennatothe300WAN-
TENNA(red)terminals.Connecta 75ohmantenna
and/or75ohmcablesystemtothecoaxialantenna
jack.
Aflexiblefoldeddipoleantennasuppliedwith
yourMR80maybeusedinurbanorinhighsignal
strengthareas.Theflexibilityofthethinflatwire
assemblypermitsittobeplacedundera rug.tacked
behindthestereoorplacedinanyotherconvenient
location.Insomecasesitmaybenecessarytoposi-
tiontheantennaforbestsignalreception.This
shouldbedonebeforeitispermanentlylocated.
Avoidlocatingthisantennanexttootherwiresor
metalobjects.Thisantennamaynotproveeffective
inhouseshavingmetalsidingormetalcladinsula-
tion.
Thecablesignalfroma localcablecompanyora
secondFMantennawith75ohmsimpedancemay
beconnectedtothecoaxialcablejack.
REMOTESCAN
TheREMOTESCANCONTROLSIGNALjackisto
beconnectedtothecablepushbuttonassembly
suppliedwiththeMR80forremotetuning.Plugthe
cableintotheCONTROLSIGNALjack.Pressingthe
pushbuttonattheendofthecablecausestheMR
80toscantothenextstation.Themodeofscancan
beselectedbytheSTATION'Sslideswitch.Inthe
PRESETpositioneverytimethepushbuttonis
depressedtheMR80willscantothenextpresetsta-
tion.IntheALLpositiondepressingthebuttonwill
causetheMR80toscantothenextstation.
IfREMOTEtuningisnotused,leavethejackfree
ofanyconnection.
SCOPE
Theverticalandhorizontalscopejacksarepro-
videdtoconnecttoa maximumperformancein-
dicatororanoscilloscopeforindicationofFM
multipathandsignalstrength.Connectthevertical
jacktotheverticalinputoftheindicatorandthe
horizontaljacktothehorizontalinput.
UNSWITCHEDACPOWEROUTLET
Thisoutletmaybeusedtopowerauxiliaryequip-
mentsuchasanantennarotatorora maximumper-
formanceindicator.Powerisavailablewheneverthe
MR80isconnectedtoa powersource.
4

FMCABLE
INPUTOR
2ND75WANTENNA
LEAD-IN
FMANTENNA
OPTIONAL
75W ANTENNA
LEAD-IN
REMOTECONTROL
PUSHBUTTON
POWERAMPLIFIER
PREAMPLIFIER
LEFTSPEAKERRIGHTSPEAKER
5
MAXIMUMPERFORMANCE
INDICATOR
OR
OSCILLOSCOPE
TOAC
POWER
SOURCE

FrontPanelInformationand
UseofControls
TheMR80Tunerhasthemostflexiblecontrol
systemeverdesignedina stereoFMtuner.Correct
useofthesecontrolswillyielda higherlevelofper-
formancethanpreviouslypossiblewithconven-
tionaltuners.
VOLUMECONTROLANDACPOWERSWITCH
TheVOLUMEcontrolhasbeenprecisiontracked
throughoutthelisteningrange(0to- 65dB)forac-
curatestereobalance.
ItsetstheoutputleveloftheVARIABLEOUTPUT
jacksandthefrontpanelHEADPHONEjack.The
FIXEDOUTPUTjacksarenotaffectedbytheposi-
tionoftheVOLUMEcontrol.TheACpowerswitchis
partoftheVOLUMEcontrol.TurningtheVOLUME
controlfullycounterclockwiseturnstheACpower
off.
TUNINGCONTROLSANDFREQUENCYDISPLAY
FrequencyDisplay
TheFrequencyDisplayindicatesthereceivedfre-
quencytothenearest100kHz.
Tuning
TherearefourmethodsoftuningyourMR80.
Automaticselectionofthetuningmethodispro-
videdbytouchsensorsassociatedwitheachofthe
tuningcontrols.
ManualTuning
WhenpowerisappliedtotheMR80,thecircuitry
automaticallyselectsthemanualorknobtuning
controlmode.Turningthetuningknobclockwise
willincreasethereceivedfrequency.Counterclock-
wisedecreasesthereceivedfrequency.
Note:WhentheMR80isoperatedbutisnotcon-
nectedtoanyotherdevice(preamp,poweramp,
antenna,testequipment,etc.),thereisa chancethe
frequencydisplaywillblankoutwhentuningwith
themaintuningknob.Thisisnormalandcaneasily
becorrectedbyreversingthe120VAClineplugorby
connectingtheMR80toanyotherequipment.
AutoScan
AUTOSCANisprovidedbytwotouchpadsim-
mediatelytotheleftofthetuningknob.Thesetwo
touchpadsstartthetunersearchingfora newsta-
tion.Thesmallarrowwilllightnexttothepad
touchedandindicatethedirectionofscanning.It
willscaninthedirectionchosenuntilitstopsata
stationorreachestheendoftheband.Attheband
endthetunerwillreverseitsscandirection.
Preset1,2,3 & 4
Thesetouchpadslocatedtotheleftofthefre-
quencydisplayselectoneofthefourpresetsta-
tions.Justtouchtooperate.A smallrectanglewill
lightabovethepadindicatingwhichpresethasbeen
selected.
RemoteSCAN
RemoteSCANofeitherthepresetsorallstations
isprovidedforasdescribedunderbackpanelinfor-
mation.
INDICATORLIGHTS
Threeindicatorlightsareprovidedimmediatelyto
theleftofthepresettouchpads.Theuppermost
STEREOindicateswhena stereobroadcastisbeing
received.Thesecond,LOCK,indicateswhenthe
tunerislockedtothestation.Thelockcircuitinthe
MR80isuniqueinthattunedfrequencyislockedto
thestation,nottoaninternalstandardasinthecase
ofmanydigitaltuners.ThisallowstheMR80tobe
tunedtoanyfrequencywithintheFMbandandlock
onthatfrequency.Otherdigitaltunerscanonlylock
onspecificchannelassignments.Thislockcircuitis
sopowerfulthatitmustbedisabledinordertotune
thetuner.Youwillnoticethatthemomentthatyou
touchanyoneofthetuningcontrolsthelocklight
extinguishesandonlycomesonwhenthestationis
properlytuned.Oncelockhasbeenestablishedit
willremainonevenifthestationbeingreceived
shoulddriftupto2 megacycleseithersideofthe
centerofthecarrier.Thus,perfecttuningisalways
assured.Thethirdindicatorlight,FILTER,indicates
whenthestereonoisefilterisinoperation.Thein-
dicatorlightsareinthreedifferentcolors:redfor
STEREO,amberforLOCK,andgreenforFILTER.
SELECTIVITYSWITCH
TwodegreesofIFselectivityareselectablebythe
SELECTIVITYswitch.TheNARROWornormalposi-
tionprovidesadequateselectivityforstereorecep-
tionevenunderseverereceivingconditions.Five
linearphasepiezoelectricIFfiltersprovidelow
distortionreceptionwiththishighdegreeofselec-
tivity.SettingtheSELECTIVITYswitchtoSUPER
NARROWaddsanadditional4-pole4-zeroquartz
crystalfiltertothefivepreviouslymentionedfilters.
UsetheSUPERNARROWpositiontoreceivesta-
tionsfromdistantcitieswhichareonchannelsadja-
centtolocalstations.Theremaybeuseablesignals
whichwereneverheardbeforewithordinaryFM
tuners.
6

SIGNALCOLUMN
AcolumnofLEDlampsrespondtothesignal
strengthofthestationbeingreceived.Thestronger
thesignalthehigherthecolumnreaches.Thereisa
controlonthetunertoppaneltoadjustthecolumn
heightforfullscalewhenreceivingthestrongest
signalinyourlisteningarea.
FILTERSWITCHANDFUNCTIONINDICATOR
TheMR80FILTERswitchprovidesautomatic
stereonoisereductiononweakstereostations.With
theswitchintheAUTOpositionthefilterwillbeon
onlywhenthestationisbroadcastinga stereopilot
toneandthesignalstrengthisbelow100microvolts.
WiththeswitchintheINpositionthefilteriscon-
nectedatalltimes.Thefilterhasnoaffectonmono
stations.Thefilterfunctionindicatorlightglows
greenwhenthefilterison.
MODESWITCH
AtwopositionMODEswitchisprovidedsothat
youmayselecteitherautomaticstereoormono
reception.IntheSTEREOpositionthetuner
automaticallyswitchesfrommonotostereomode
whena pre-determinedsignaltonoiseratiohas
beenreached.IntheMONOpositionallstationswill
bereceivedmonophonicallybuttheSTEREOindicator
willlightifthestationisbroadcastinginstereo.
HEADPHONEJACK
AHEADPHONEjackisprovidedtodrivelowim-
pedancedynamicheadphonesfromaninternal
poweramplfier.
SCANCONTROL
TheSCANcontroladjuststhespeedatwhichthe
tunersearchesforthenextstation,whenusingthe
AUTOSCANmodeoftuning.Ifthedialiscrowded
withstationsusea slowscanspeed.Iftherearefew
stationsfastscanningcanbeused.
MUTINGCONTROL
MUTINGsuppressesthebackgroundnoiseand
hissnormallyheardbetweenstations.Turningthe
controlcounterclockwisetotheOUTpositiondis-
ablesthemutingcircuits.Turningthecontrolclock-
wiseincreasesthesignallevelrequiredtounmute.
ThiscontrolalsoadjuststhesensitivityoftheAUTO
SCANtuningcircuitsandthenumberofstations
youwillreceivewhenusingthistuningmode.
7

TopPanelInformationand
SecondaryControls
Onthetopofthechassisbehindthefrontpanela
recessedpanelcontainsthesecondarycontrols.
WhentheMR80isinstalledinthecabinetaccessto
thispanelmaybegainedbydepressingthetwo
PANLOCbuttonsandslippingtheunitpartiallyfor-
ward.
Preset1 thru4
ThePRESETtuningadjustmentsareusedtoset
thereceivedfrequencyforeachpreset.Toseta
presettothedesiredstation,touchthecorrespond-
ingpresetpadandatthesametimeadjustthe
presetcontrolonthetoppanelforthedesiredfre-
quencyindication.Youmusttouchthepadwhile
tuningtoholdthefrequencylockcircuitinactive,
otherwiseerroneoustuningwillresult.
Preselect
TheRFPRESELECTswitchswitchesanaddi-
tionaltunedcircuitbetweentheantennaandthe
firstRFstagetoimmunizeagainstoverload.Usethe
preselectorinverystrongsignalareas.
Input
TheINPUTswitchselectseitheranantennaor
cableastheRFinputsource.TheCABLEinputmay
alsobeusedasa secondantennainput.
Lock
Thisswitchwilldisablethelockcircuitsonly
whenthemaintuningknobisinuse.UsetheON
positionforallnormalreception.SwitchtotheOFF
positionwhenthereceivedstationhasa deepfade.
Thispreventsthefrequencylockcircuitfromchang-
ingtuningtolocktoanadjacentstrongerstation.
De-emphasis
The50/75msbuttonselectsthecorrectde-
emphasisforyourcountry.75msisusedontheNorth
Americancontinentand50msisusedinWestern
EuropeandtheFarEast.25msde-emphasisisalso
availablebydepressingthebuttonmarked
Note:Thenormaloperatingpositionofthefive
pushbuttonswitchesisfortheswitchestobeinthe
outorupposition.
SignalStrength
Usethiscontroltosetthesignalstrengthcolumn
tofullscaleforthestrongeststationinyourarea.
Thiscontrolisa sensitivityadjustmentforthesolid
statesignalstrengthindicator.Itmerelyadjuststhe
heightofthecolumn.Itdoesnotaffectthesensitiv-
ityofthetuner.
8

PerformanceLimits
PerformanceGuarantee
Performancelimitsarethemaximumdeviationfrom
perfectionpermittedfora Mclntoshinstrument.We
promiseyouthattheMR80,atthetimeofitspur-
chase,iscapableofperformanceatorexceeding
theselimitsoryougetyourmoneyback.Mclntoshis
theonlymanufacturerthatmakesthisguarantee.
Tuning:
88to108MHz
AntennaInputs:
One300Wbalancedandtwo75Wunbalanced.
IntermediateFrequency:
10.7MHz
Sensitivity:
9.3dBf(1.6mV)for35dBofquieting
14.7dBf(3mV)for50dBofquieting
13.2dBf(2.5mV)for3%totalnoiseandharmonicdis-
tortion
SignaltoNoiseRatio:
75dBbelow100%modulation
HarmonicDistortion:
0.2%20Hzto15kHz,monoorstereo
Typically,0.08%at1000Hz
IntermodulationDistortion:
0.15%monoorstereoforanycombinationoffre-
quenciesfrom20Hzto15,000Hzwithpeakmodula-
tionequalto100%orless.Typically0.1%
FrequencyResponse:
MonoandStereo± 1dB20Hzto15kHzwith75,50
or25mSdeemphasis
CaptureRatio:
1.5dB
Selectivity:
Adjacentchannel
Alternatechannel
SpuriousRejection:
110dB
Narrow
8dB
90dB
SuperNarrow
60dB
110dB
TunerIM(RF):
-23dBmfor2 signals1MHzapart
TunerInterceptPoint:
-10dBm75W
ImageRejection:
90dB
MaximumSignalInput:
8voltsacross75W(1W)antennaterminalwillnot
increaseharmonicorintermodulationdistortion.
AudioHum:
75dBdownfrom100%modulation
Muting:
70dBnoisereductionbetweenstations
MutingThreshold:
2mVto1000mV
SCARejection:
60dBminimum
StereoSeparation:
50dBto1000Hz
StereoFilter:
10dBnoisereduction
AudioOutput:
Variable:
2.5Vinto47k
Fixed:
1Vinto47k
GeneralInformation
PowerRequirements:
120volts50/60Hz.25watts
SemiconductorComplement:
57Transistors
68IntegratedCircuits
81Diodes
4LEDDisplays
18LED's
7NeonLamps
MechanicalInformation
SIZE:Frontpanelmeasures16incheswide(40.6cm)
by5 7/16incheshigh(13.8cm).Chassismeasures
143/4incheswide(37.5cm)by4 13/16incheshigh
(12.2cm)by13inchesdeep(33cm),includingcon-
nectors.Knobclearancerequiredis1 1/4inches(3.2
cm)infrontofmountingpanel.
FINISH:Frontpanelisanodizedgoldandblackwith
specialgold/tealnomenclatureillumination.
Chassisisblack.
MOUNTING:ExclusiveMclntoshdevelopedprofes-
sionalPANLOC
WEIGHT:27pounds(12.2kg)net,39pounds(17.7kg)
inshippingcarton
9

PerformanceCharts
SIGNALINPUT
10
SIGNALINPUT