Sharp GF-777 Installation instructions

GENERALDISASSEMBLYINSTRUCTIONS
FOR
RE-BELTING&REPAIR
OF
NON-FUNCTIONALFF &REW
INSTRUCTIONS&PHOTOS
BY
BOBBYJENKINS*
AKA FATDOG
www.stereo2go.com
*-Exceptwherenoted
Note:Someofthepicturesdidn'tturnoutgreat, butthey shouldbegood enough togetyou through
theprocess.

UNPLUG THE BOOMBOX AND REMOVE ANYBATTERIES!!
Removeall oftheknobsandswitchcoversonthefrontsideoftheboombox. Iliketolinethemup in
theorderItookthemoff oftheboombox.
Turntheboomboxaroundandremovethescrewsholdingtheboomboxtogether. Ifyoudothispart
right, all ofthescrewswill stayintheirrespectiveholes. Justincasethethreadsareslightlydifferent
foreachscrew, youlessenthepossibilityofwearingoutthethreadedposts.

Don'tyankorpull thebackoff withforce. Therearesomeplugsthatneedtobedisconnectedfirst.
First, therearetwowiresfortheantennasthatneedtobedisconnected. Takenoteofthecolorsofthe
wiresandwhichpostthewireswentto.
Atthebottomofthecase, thereisaplug forthepowerlead. Disconnectthisplug. Youcannow
CAREFULLYremovethebackoftheboomboxcompletelyandsetaside.

LookingattheinternalsoftheGF-777, therearefourmainareasthatkeeptheprimaryelectronicsin
place, asmarkedbythearrows.
Removethefar-rightscrew. Itwill bealongscrewwithawasher. Removethescrewlocatedatthe
topoftheboomboxwherethearrowispointing. Finally, removethescrewatthebottomofthe
vertical, blackspeakerconnectorblock. Also, removethemetalbarthatholdstheheadphoneand
micboardsinplace.

Thefourth, andfinalarea youneedtolookatisatthefarleftoftheboombox(lookingfromthe
back). Removethescrewsforthemetalplateandthepowerswitch.
Backonthevertical, blackspeakerconnectorblock, therearesomeplugsontheleftunderside.
Disconnecttheplugsasindicatedbythearrows. Oneshouldhaveblueandpurplewires. Theother
shouldhaveyellowandblackwires.

Almostthere. Tothefarrightoftheboombox, thereisanotherconnectorbyoneofthewoofers.
Disconnectthisplug.
Now, Icannotstress thisenough-VERYCAREFULLY!!! -liftandremovethecompletebracket
housingfromtheinsideoftheboombox. Donotforce anythingatthispoint. Ifsomethingiscaught,
findoutwhatitisbeforecontinuing.

Thiswouldbeanexcellenttimetocleanoutsomedustbunniesandgeneralnastiness fromthefront
cover.
Therearefivescrewsholdingthetapedeckmechanismtotheplastichousing. Fourofthescrewsare
ratherobvious.

Thelastoneissomewhathidden. It'sontheotherside, partiallyobscuredbytheblack, input
connectorblock. Removethescrewsholdingtheinputconnectorblocktothehousingandthen
removethelastscrewholdingthetapedeckmechanism.
Thereisalsoaplug (notpictured)directlyunderneaththeinputconnectorblock. Disconnecttheplug
afterremovingthescrewsfortheblock. Next, disconnecttheplugsasindicatedbythebluearrows
inthepicturebelow. Also, itmighthelptoloosenthesquarePCboardabovetheplugsbyGENTLY
pryingbackthecatchingpostsasindicatedbythepurplearrows.

Ifyouneedtoreplace thebeltthatoperatesthetapecounter, payspecialattentiontoitslocation. One
oftheposts/spindlesisunderneaththedialfaceplateanditissomewhatawkwardtogetthebelt
aroundthepostbeforeconnectingthetapedeckspindle. Inthisexample, I'vealreadyreplacedthat
belt. So, inordertokeeptensiononthebelt, Idecidedtoloopitontooneofthefrontswitches.
Believeme, thiswill definitelyhelp.
Nowthatthetapecounterbeltisdisconnected, youcanliftouttheactualtapedeckmechanism. BE
VERYCAREFUL!! Thereisanextensionthatishookedontoablack, plasticarmunderneaththe
dialfaceplate. Youwill havetoworktheextensionoff thearmbeforecompletelyremovingthetape
decks.

Once thetapedecksareout, flipthemoverandremovethescrewsasindicatedinthepicturebelow.
Thethree screwsontherightsideofthepicturemightnothavetoberemoved, butitmadethings
easierforme.

Wefinallyreachthebelts!!!
Removeall theoldbeltsandCAREFULLYturnthetapedecksover. Youwill needtoremovethe
flywheelswithoutlosingthelittlewasherthatslidesovertheposts.

Oneofmyflywheelswasslightlydifferentfromtheother;therewasasmall "scoop"intheouter
edgeoftheflywheelforDeck#2. Ifyoursisthesameway, payattentiontothatonreassembly.
Nowthattheflywheelsareremoved, cleanthesmall idlerwheelsthatwerehidden. Therearetwo
idlerwheelsforeachtapedeck. Itprobablywouldn'thurttocleantheplasticontheflywheeltoo.
Once theidlersareclean, inspecttheentiretapedeckmechanismfordust, dirt, andgeneralgrime.
Cleanitnowbeforereassembly.

That'sit!! Nowthefunpartbegins-puttingeverythingbacktogether. Replace theflywheelsand
theirsmall washers–steadyhandsareamust. YouDO NOT wanttodropthewashersandlose
theminthetapedeckmechanism!
Install thelarge, flatbeltaroundtheflywheelandaroundtheplasticpostsasillustratedinthepicture
below. Thisisatremendoushelpwhentryingtogetthebeltsaroundthemotorspindle. Install the
secondarybelts. Makesurethatthesquarebeltsarenottwisted. Reattachthetapedeckplatewith
themotorsanduseasmall hooktoreleasetheflatbeltoff theplasticpostsandontothemotor
spindles. Beverycarefulanddon’tscratchthePCboard!
(PhotocourtesyofFrankJiang akaFYJ2972)
Continuereassemblingtheboomboxbyretracingthestepsoutlinedinthistutorial–reverseorder, of
course. Doublecheckall plug connectorsandscrews. Youdon'twanttoendup withscrews
remaining!
Afterre-beltingandcleaningtheidlerwheels, theGF-777 shouldPLAY, FF, andREWwiththebest
ofthem!It'samazingwhatalittleisopropylalcoholandnewbeltswill do.

Beforeclosingup completely, youmightwanttoadjustthemotorspeedforeachdeckandcheckthe
azimuthontheplayheadsforeachdeck.
Toadjustthemotorspeed, insertasmall, flat-headscrewdriver(preferablyplasticandapprox. 3/32”
headsize)intotheopeningonthebackofthemotor. Carefullyturnthescrewdriveruntil youfeel
theslotofthescrew. Turningthescrewclockwisewill increasethemotorspeed. Likewise, turning
thescrewcounter-clockwisewill decreasemotorspeed. Ifyoudon’thavethe“official”meansof
testingcorrectspeed(e.g. test-tonetapes, oscilloscopes, etc.), youmighthaveluckwithmymethod.
IhadacommercialcopyofaU.T.F.O. cassetteasmytestcassette. IrippedmycommercialCDof
thesameU.T.F.O. albumandconvertedthetrackstoMP3files, whichwerethencopiedontomy
MP3player. IplayedthetapeandMP3playeratthesametimeuntil thetrackswerematchedas
closelyaspossible. Whenyouhaveanextremelyslowphasingeffect(whenthetwosourcesseemto
canceleachotherout), you’vegotatapespeedthatwill beveryclosetotrue.
Toadjusttheazimuthfortheplayhead, firstremovethefaceplatesfromthecassettedoors. You
will notice underthetapedoorthereareacoupleofsmall holes, maybethree. Youcanaccess the
tapeheadthroughthelargestoftheholeswithaverysmall Phillips-headscrewdriver. Putatapein
andpress PLAYand, verygently, adjustthetapeheadbyturningthescrewleftorright. Tryjusta
littleatfirstandyou'll notice thesoundchange. Usingqualityheadphoneswill helptremendously
withthis. Youshouldbeabletolocatethecorrectpositionbeforetoo long!
(AzimuthtipcourtesyofMirkoHenriquezakaBeatbox)
Ihopethistutorialmadesense. Ifyouhaveanyquestions, pleasecontactFatdogonthe
Stereo2Go.comforum!
ThanksFYJ2972, Litfan, Beatbox, andmanyotherswhoseadvice allowedmetorepairmyGF-777!