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Service Manual RCA Model 18V100 Home TV Programmer

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Studio II

<, Home TV Programmer, Model 18V100

Operation

^•

Testing

^•

Disassembly Parts List

^

PRODUCT SAFETY

NOTICE StudioIIusesanisolatedpower supplytooperate the electronic circuitry.Theleakage currentto ground ofthis powerunitshouldbe checkedattimeofgamerepair.See Page 9for testprocedure.

TESTER CARTRIDGE AVAILABLE

As anaidto servicingthedigitalelectronicssystems of StudioII,a test cartridgeisavailable atnominalcostthrough

RCA

Parts Distributors.Called"TesterI",thecartridge plugs into the slot intheconsole and checks out thedigital circuitry inabout 30 seconds. See Page 4for descriptionand Page 15 forordering information.

SERVICE

PARTS

LIST

AVAILABLE

For thoseorganizationsplanningto serviceStudioIIvideo games,a kitofStudioIIrepair partsisavailablefrom

RCA

Parts Distributors.Thiskit includesallof the partsnecessary to serviceStudioIIunits inthefield.See Page15for descriptionandforordering information.

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Table of Contents

Page

STUDIO

IIPC

BOARD EXCHANGE QUESTIONNAIRE

15

DESCRIPTION 3

Control Console 3

SelectorSwitch Unit 3

Power Supply Unit 3

STUDIO

IISERVICING - 4

System Checking 4

System Connections 4

TestProcedures 4

Control Dissassembly ¹¹

ComponentReplacement Procedure 11

Clock Frequency Adjustment Procedure 13

PC

BOARD EXCHANGE

¹⁴

ExchangePlanDescription 14

PCBoard Packing and Shipment 14

STUDIO

IISERVICE

PARTS

KIT 14

REPLACEMENT PARTS AND ACCESSORIES

¹⁵

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^

^

Information furnished byRCAisbelieved tobe accurate andreliable.However, no responsibilityisassumed byRCAforitsuse:nor for any infringements of patents or otherrightsof third partieswhichmayresultfromitsuse.Nolicenseisgrantedbyimplication or otherwise under any patentrightofRCA.RCAretainstherighttomakechangesinthisproductat itsdiscretionasmaybe periodically required.

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POWER SUPPLY

UNIT

¹⁸

FOOT

CONSOLE CORD

TV/STUDIO

II

SELECTOR SWITCH

KEYBOARD A

ON/OFF INDICATOR LIGHT

STUDIO

^II

CONSOLE CLEAR BUTTON

KEYBOARD

B

CHANNEL 2/CHANNEL

3

SWITCH SOUND ON/OFF SWITCH (UNDER CONSOLE)

Figure1. StudioIIMajor Assemblies

Description

GENERAL

DESCRIPTION

StudioIIisa sophisticated,microprocessor-based system forhomeentertainmentusing abroadcast

TV

receiver asthe display device.

Heart of the StudioIIisa solid-state,40-pinintegrated circuitmicroprocessorthatfunctionsas amicro-miniature computer. Itprovides centralcomputercontrol for a great varietyof educational and entertainment programs. Program memoryfor five built-ingames

-

"Doodles", "Patterns",

"Bowling", "Freeway", and "Addition"

—

isincludedinthe console.

A

receptacleintheconsole acceptsplug-inprogram cartridgesformanyadditionalgames suchas"Tennis",

"Baseball" and "Blackjack".

SYSTEM

DESCRIPTION

StudioIIconsistsofthreemajorpieces:

Control Console

—

Houses the keyboards andallelectronics forprogramselectionandprocessing.Allelectronicsinthe

console(digital,RFoscillator/modulatorand audiocircuits) areona singlePCboard.Signalinformationfrom the console

istransferredto theSelectorSwitch Unit througha single coaxial cable.Thissamecable carries

DC

power from the SelectorSwitch Unittotheconsoletooperate theelectronics.

SelectorSwitch Unit

—

Formsthe interfacebetween the Control Console, the StudioIIPower SupplyUnit,the

TV

receivingantennaand the

TV

receiver.

A

two-position switch allowsthe

TV

receiver tobeconnected conveniently toeither theStudioIIorto thereceiver'santenna system.Thisswitch also serves as thegame's on/offswitch.

PowerSupply Unit

- A

sealed,120

VAC

to9

VDC

adapter witha 6-foot(1.8m) cordand plugthatconnectsto aminia- ture(3mm)phonejackon the SwitchSelector Unit.The9

VDC

^iscoupled to the game's 18-foot (5.5m)coaxialcable through anRF-filtering circuithousedinthe SelectorSwitch Unit.

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Studio

II

Servicing

TherecommendedStudioIIserviceprocedureistodeter- mine whether the problem^isinoneoftheperiphery components,theinterconnectingcablesor intheconsole itself.IfthePCboardintheconsoleisfoundtobefaulty, itmust be returnedto

RCA

for repairon an exchange^basis.

SeePage14.

IMPORTANT:

Noattempt should bemadeto adjust or repairaninoperativePCboard—with theexceptionofthe clock-frequency adjustment described on Page13.

As anaidto servicingStudioII,a test cartridge (seebelow)

isavailablefromRCA. Thecartridgeisnotessentialto service StudioII;however,itdoes provideaquickand convenient meansfor isolatingmalfunctionsinthedigitalsystems.

WhenaStudioIIcomesinfor service,itisimportantthat you haveallthree assemblies: SelectorSwitchUnit,Power Supply Unit and Console.Ifthecomplaintinvolvesoneor moreplug-in cartridges, theseshould be includedaswell.

SYSTEM CHECKING

Checking StudioIIoperationcanbedone quickly and easilyusing a test cartridge availablefrom

RCA

(seePage 15 forordering information). System performance canalsobe checked by operating eachbuilt-ingamefunction;however, thisproceduretakesmoretime thanthe test cartridgecheck.

SYSTEM CONNECTIONS

StudioIIconnectsto the300-ohm

VHF

antenna terminals ofany

TV

receiver.Figure2describesthehookupofthethree subassemblies.Figures 4,5 and 6descirbe thehookups with typical video-tapemachinesandtypical cable

TV

setups.

Recessedontheunderside oftheconsolearetwoslide switches(Fig. 3).Oneswitchesthegamesound(beeper)onor offwhile the otherchanges operating channel. StudioIIoper- ateson

TV

Channel 2or

TV

Channel 3 depending on the positionofthe switch.The switch should besetontheunoc- cupied channel;or areaswhere both channelsareoccupied, onthechannelwiththeweakest broadcastsignal.Units areshipped from the factory with the switchinChannel 3 position.

Slidethe switch onthe SelectorSwitch Unit(Fig.7) to

"Studio11".This sends powerto theconsole(indicatedbythe redglowofthepilot lighton the console) and connects^itto the

TV

receiver.StudioIIisnowreadyforoperation.

TEST PROCEDURES

Pressthe"Clear"button ontheconsoleandpressKey4on left-handKeyboard

A

(Key A4). ThissetsStudioIIfor"Free- way"and thetrack (Fig. 8)appears immediately.Ifnecessary, adjustthereceiver's finetuningandvertical/horizontalhold controls.

OperationalChecks TestCartridge (SeePage7forprocedureusing built-inprograms).

Thetest cartridge,whichplugs into the cartridge sloton the StudioIIconsole,scansthedigitalcircuitry fortroublewitha rou- tinethat takesabout30seconds.Ifitfinds amalfunction, thefact

SELECTOR SWITCH

TOANTENNA

\0>

POWER

SUPPLY*use 75ohm/300 ohmmatching transformerifrequired.

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Figure2.StudioIIConnection Diagram

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Figure3.LocationsofChannelChange andSound On/Off Switches

ANTENNA

I VIDEO CASSETTE MACHINE

TWIN

.STUDIOII

SELECTOR SWITCH

BOX

TWIN TV

RECEIVER

LEAD? LEAD^

^

-^ANTENNA/ TERMINALS

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Figure 4. SelectorSwitchBoxConnectsBetween Video CassetteRecorder and

Home

Receiver

CO-AX CATV. TWIN TWIN

TUNER

STUDIOII

SELECTOR SWITCH BOX

TV RECEIVER

CABLE LEAD^ LEAo7

^ANTENNA, TERMINALS

Figure5.SelectorSwitchBoxConnects Between

CATV

Tuner and

Home

Receiver

f

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r

isindicatedon the

TV

screen;ifthereisnotrouble,the cartridge setsupa test for thetwokeyboards.

NOTE: TheTestCartridge requires substitution ofthepowerunitduringtest.Usethe special

500mA

powerunit (see Parts List) instead of the originalpowerunit.

1.Pressand hold "Clear" button on Studio^{IIconsole.In-} sert TesterIcartridge into slotwhile holding "Clear" button.

NOTE:Insert cartridge intoconsole withlabel sidetoward "Clear" button. Followlabel directions concerning removalofconductive rubberstrip coveringthe plug.

2.Release"Clear" button.

A

pattern similar tothatof Fig.

9a appears onscreenimmediately, andTesterIbeginsits scanof thesystem(indicatedbythe black streakmoving throughthewhitefieldinthelowerhalf ofthepattern).Ifthe patternfailstoappearor a patternother thanthatshown appears,afaultychipisindicated.ReplacePCboard.

Inabout11seconds,thefirstscaniscomplete.Thedisplay shifts tothepatternshowninFig.9bwithawhitestreak scanningablackfield.This scan takes another1 1seconds. At theendof thesecondscan, thesystem changes thepatternon the lowerhalfto a series of transient verticalwhitelineson blackand thena seriesof blacklinesonwhite.This sequence takesabout 2 seconds. Attheendof this shortsequence,the pattern againshifts-to that illustrated in Fig. 9c. Thisindi- catesallmemoriesoperational.

A

digit or digitsappearingin the"checkerboard"patterninthecenter of the screen, as showninFig.9e, indicateschipfailure inthePCboard and the board must bereplaced.

Ifthecheckerboard appearsas in Fig. 9c,touch the keys

-

oneat atime

-

ofKeyboard A, and then Keyboard^B.As each key switchcloses, the digitonscreenshould changeto a checkerboardsquare.(Ifanydigitremains onscreen afterkey actuation, thekeyboardisdefectiveand must be replaced (seePage11).Whenallkeyclosures arecomplete(indicating

CATV CO-AX CATV

MATCHER

STUDIOII

SELECTOR SWITCH

BOX

ANTENNA TERMINALS

TV RECEIVER

Figure6.SelectorSwitchBoxConnects Between

CATV

Cable Matcher and

Home

Receiver

ANTENNA TERMINALS

£1

nc/i

TV -« »- STUDIOII

o

-T®~L

STICKY TAPE

TO CONSOLE

Figure8.Adjust ReceiverforSharp"Freeway"Display

(d) Operable Keyboards andElectronics

mmmm^m

(e) BadKey A7andDigital Failure

Figure7.SelectorSwitchBox Figure9.Tester1ScreenPatterns

laxoos ITQdVO3HV0

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Figure 10.OverallBlockDiagram of Studio^IISystem

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satisfactorykeyboardfunction), the pattern shiftsto the

"OK"

patternofFig. 9d.Thepattern flip-flopsbetweenblack-on- white and white-on-blackuntil the"Clear" buttonisactuated.

Ifthe"Clear" button functions normally,thewhole sequence starts again asthe buttonisreleased.This completes the

"TesterI" test.

NOTE:Reconnectthe originalpowerunit into thesystem. Store thespecial unitwith thetest cartridge for future use.

Operational Checks UsingBuilt-inPrograms The followinginstructions are foroperating thebuilt-in

"resident" gamesto evaluateStudioIIperformance:

"Bowling"Game

Press"Clear"key. PressKeyA3(left-handkeyboard).

Screenwill display"scorecard"(Fig. 11) forabout 3 seconds and immediatelysetsupalley (Fig. 12)with bowlingball moving up anddownat theleftside.

PLAYER A SCORE

PLAYERB SCORE

ana noa

FRAME NUMBER

Figure 11.Bowling "Scorecard" Display

STRAIGHT, KEY^«r5

Figure12.BowlingBallReleaseKeys

Keyboard

A

isinaction: Pressing

A5

releases a straight balltowardthe pins;Key

A2

sendsa ballwithaleft(upward) hookwhileKey

A8

delivers a right(downward)hook(Fig. 12).

Knocking outallpinson one throwregistersa strikewitha scoreof20 ("ST- 20"atlowerleftcorner ofalley);twothrows, a score of¹5("SP-15" onscreen).Thescorecard reappearsfor about 3 secondsafterthesecondballisthrownorallpins are downed.Player2 thenplays right-handKeyboardB.

OPPOSING CAR CONTROLLED BY THE COMPUTER

PLAYER'S CAR

Figure13."Freeway"Screen Display

"Freeway" Game

Press"Clear"key. PressKeyA4;racetrackappears onscreen (Fig. 13). PressKey BOtostart race. Pressand holdKey B4to steer car toleft;Key B6steers car to right. Press

A2

tospeed uprace (throttle);Key

A8

slowscar (brake).Object:Accum- ulate"mileage"by avoidingcollisionswith computer-con- trolled(narrow-bodied)carinatwo-minuterace.Atthe end oftherace,thescreen displaysthedistance traveled.

PLAYERA SCORE

PLAYERB SCORE

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THREE NUMBERSTO BEADDED

Figure14."Addition" Screen Display

"Addition" Function

Press"Clear" key.PressKey A5. Screendisplayappearsas showninFig. 14. Player has fivesecondstoadd thethree digitsinthe lower group andpressthecorrectanswer on Key- board

A

or B.For example, the"130"onFig.14 adds up to

"4". Punch

A3

orB3toscore.The sooner thecorrect totalis entered,the higher thescore.(Maximumscore foreach entry

is11).Ifthewrong^totalisentered,the keyboard "locks out"

andthe player getsno second chance on the on-screen com- bination.Thereare20setsintheruninrandomorder.

"Patterns"Function

Press"Clear"key. PressKeyA2. Screen remainsdark.

PressKeyB4,thenKeyBO.Thecomputer then "paints"the screenwhite fromrighttoleftand from bottomto top.Once thematrixisallwhite,the computer thenpaintsthescreen black. PressKey B5, thepaintingstops or freezes, pressKey BO,paintingresumes.

The keysofKeyboard B "write" onthe screenaccording tothewhite arrowheadson the keyboard(Fig.15).Toform aninteresting pattern, press"Clear"key,thenA2,B215 times,B6once,and then BO.Thememorystoresupto130 keyentriesor"moves". After 130 moves, the computerauto' matically starts to repeatthepattern.For129orfewer moves.

Key BOmust be pressedto starttherepeat cycle.

KEYBOARDA KEYBOARDB

f

aha

I

nan

;

a

l

B

^StudioII

©

CLEAR KEY#0

STARTS COMPUTER PATTERN

Figure15.Keyboard"B" MovesSpot According to White ArrowheadsonPanel

"Doodles" Function

Press"Clear"key. PressA1.Singledot appearsonscreen at lowerleftcorner.Use keys onKeyboard Btomovespot according to white arrowsonpanel (Fig. 16).Key B5leaves a trailasplayer"writes" withKeyboardB. PressingKeyBO leavesnotrail.Retracestepsto erase linesalreadywritten.

Figure16.In"Doodles", etchasketchelectronicallywith the

"B"keyboard

Keyboard Tests

If"TesterI" cartridgeisavailable,useitto isolatekeyboard malfunction.IfTesterIisunavailable,thekeyboards can be testedusingthebuilt-in"Addition" game:

Step1:Punch up "Addition"game(Key A5).Soundswitch must be "on".

Step2:Whenthe three-digitnumberappears onscreen, enter a series ofwronganswers, beginning withA1.As each buttonispressed,the beeper sounds,indicating the particular buttonisoperational.Thebeepersounds only during thefive secondsthatthe random-orderdisplayisonscreen. Usually, theentirekeyboard can be checked during thefive-second display.Ifany keyfailstosound,thatkeyisfaultyand the entirekeyboard should bereplaced.

am ana 13D

KEY #5 START

PLAYER A ENTERS

Q

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\___

\

io ni B

o\po

DDD DDD a

Studio11 DDD

DDDD DDD

<

©

CLEAR I

^

—

—

^.

—

PLAYERB ]ENTERS 'SUM

Figure 17.Using"Addition" toCheck Keyboards

"Double-Hit"KeyboardComplaints

Someearlyproductionunits (SerialNos.37125and lower) occasionally exhibit akeyboard malfunctiontermed "double- hit"whenStudioIIoperatesinthe"Patterns"mode(un- wanted dots appear onthe screen,and the beeper sounds twiceforonlyone keyentry).Theonlyremedyfordouble hitsiskeyboard replacement.

CoaxialCable Tests

Thecoaxial cable carriesmodulatedRFfrom the console and

DC

from the powerunit.Use anohmmetertotestthe cablefrom the plug end(Fig.18).

A

goodcablemeasures 5 to

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CABLECONNECTOR

I—

/©n —

OHMMETER N

Z>««">

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I

II

4-

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Figure 18.Checking ContinuityofCo-ax Cable

8

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50ohmsresistancewith negativeohmmeterpolarityonthe center conductor. (Withpositive polarityon center conductor, resistanceshould be between 20 and 30k ohms.) See "Coaxial Cable Replacement".

SelectorSwitch Unit Tests

The quickesttest for atroublesomeSelectorSwitch Unitis substitutionwithanewunit (see Parts List).Ifanewunitis unavailable, use a

DC

voltmeter andohmmetertocheckunit circuitry (seeschematic ofFig.19) foropenor short-circuited components.

TWINLEAD TVSET CONNECTION GAMEINPUT

TERMINALS

A A

>-9- (PHONOJ1

JACK)N

H

TRANSFER SWITCH

1

O ^1-

I 0= 1o r

J3 TVANTENNA

TERMINALS

STUDIOI

RFC2

A ^A

DCINPUT TERMINALS (PHONE JACK)

Figure19. Schematic,SelectorSwitch Unit

Whenthe switchisinthe "StudioII" position,itconnects thecoaxial cablefromtheconsole to the twinleadand com- pletes the

DC

circuitbetweentheconsole andpowersupply.

Withtheswitchin the"TV"position,itdisconnects the con- soleand formsa circuitbetweentheantenna terminals and the twinlead fornormal

TV

reception.

IftheSelectorSwitch Unitisdefective,itmust be replaced (see Parts List) sinceitcannot besatisfactorily repaired inthe field.Itiscarefullymanufacturedso asnot to exceed theRF radiation limits specifiedby the FCC.

Ifsnowypicturesoccurinthe"TV"position orStudioII

cannot be shutoff,check antenna connectionsfor short circuits

to the metalboxorrivetsholding terminal board.Ifeither antennaleadtouchestheboxorrivets,snowypicturesmay result.(Lateproductionunitsuse insulated rivetswhich eliminate problem))

Power Supply Unit Tests

The Power Supply Unit operates betweencarefullychosen voltageandripple limits.Tocheckunit for satisfactoryopera- tion,connectunit asshowninFig. 20.

DC

output under these conditions ranges between 8.5 and 10V. Ripple onthis

DC

(measured withoscilloscope)must not exceed¹

V

peak-to- peak. Replaceunitifbeyondthese specifications (see Parts List).

Leakage Current Test

With the Power Supply Unit plugged^intoan

AC

outlet, checkforleakage currentto earthground on bothpolesof thephoneplug, asshowninFig.21,usingan

AC

milliam- meter. Leakage currentmustnot exceed0.5mA.Reverse

AC

plugpolarityand recheck leakagecurrent.

EARTH GROUND

Figure 21.

AC

Leakage Test

NOTE:Ifpowerunitchecksout

OK

butisinoper- ativewith operable StudioIIconsole,checkfitof plug-in jack.Someearlyproductionplugsandjacks havetolerances that conflictand prevent adequate plugpenetration.Solution to problemisoften simply to increase effective lengthof plug byfilingthejack slightly asshowninFig. 22.(Use sharpknifeto remove anyuntrimmedmoldflashfrom plugif present.)

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-ft-

TO120V

ACLINE ADJUST FOR

250mA ON MILLIAMMETER

FILEOR SHAVE SLIGHTLY TOINCREASE PLUG PENETRATION

—^

Figure 20.TestingPowerUnit OutputforVoltage and Ripple Content

Figure22. RemovalofMaterialfromFrontEdgeofJack

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Figure23.StudioIIConsole Assembly

10

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CONSOLE DISASSEMBLY

Theconsoleconsistsofsix separatesubassemblies:thetwo halvesof the cabinet, printed circuitboard,twokeyboards, anda"Clear" switch/power-onindicator.

The upper and lowerhalves ofthe cabinetareseparated by removing 5Phillips-headscrews.With thebottom coverre- moved,theundersideof the printed circuitboardisexposed.

LiftthePCboardupatthe cartridgesocketside asshownin Fig.24. Thisexposes thecomponentsideof the board.The board stands onedgeifsetbetweenpillar (near"Clear" switch) andflangeofcabinetupperhalf asshown.

3.Releasethekeyboardfromtheconsoleby unlatching two browncoloredlatches as illustrated.Keyboardisnow freeof console.

CARTRIDGE RODE ^ —"***

^k^===^

'^A ^{x% *}

\$

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SV/

^/^^^^^

"^-^ CART

X^Ss^^ SOCKET

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SL0T

TOP HALF OF CABINET

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Figure24. PCBoardinWiring AccessPosition

NOTE:The channel-change and sound on/off switches, plug-in cartridgeconnectorand other componentsmountedon thePCboardarenot fieldreplaceable. AllPCboardfaults(except speaker) requireboard exchange.

CAUTION:Tunersprayscontainingsiliconmust not beusedonslideswitches. Irrepairableswitchdam- age will result.

COMPONENT REPLACEMENT PROCEDURE

PCBoardRemoval

Disconnectblack,whiteand yellow wires from board;un- soldercoaxialcablefrom board andcarefully pulloutkey- board ribbonleadsfrom

RC

board connectors. See"PCBoard Packing and Shipment"forboardexchangedetails(Page 14).

Keyboard Replacement

1.Keyboard replacementrequiresconsoledisassemblyas described above.

2.Unplugtheribboncable ofthe defectivekeyboardfrom theribbonconnectoronthePCboardbypullingthe ribbon straightoutoftheconnector.

Figure25.ReleasingKeyboardfromConsole

4. Installnewkeyboard by feeding ribboncablethrough openinginconsolebeforelatchingkeyboardinplace.

5.Push ribboncable intoconnector.

NOTE: SomeStudioIIunits useunenclosedrib- bon connectors onPCboard.Ribboncablemust centerintheconnectorsothatall1 1leadscontact forproperoperation.

6.Ifribboncablefrom keyboardfailstomakegood contact inconnector, trimback 1/16inchfrom edge with ordinary householdscissorsto exposefresh contact.

Figure26.Trim Ribbon Cable withScissorsto Repair DamagedEdge

Coaxial Cable Replacement

1.Remove bottomhalfofconsolecabinet.Pryoffmetal shieldcoveringend ofcoaxial cable.

CAUTION:Prycarefullyso asnottodamagefoil wiringonPCboard.

2.Disconnectcableby unsolderingshieldfirst.Donot overheatfoil.

3.Installreplacementcable asshownbysolderingcenter leadfirst.

4.Re-install shieldcovercarefullyandfirmly.Centercoaxial

11

cable in slotincover(Fig.27). Shieldmustbefullyseatedto minimizeradiationofmodulated^carrier.

4.Fromundersideof cover,bend clipped^pigtailsbackand collapseblackplasticholder with needlenosepliersor diagonal cutters.Removeholder from consoleholes using pliers or cutter.

5. Installnew

LED

holder. Pressholdergently intoholein console coveruntilitclicks into place (Fig. 29).

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Figure27.DisconnectCo-AxShieldFirstto ReplaceCable.

Resolder Center LeadFirstonInstallation.

Do NotOverheatFoil inBoard.

LED

indicatorReplacement

NOTE:Installinganew

LED

ⁱⁿthe consolere- quires the use of a special tool thatcan befabri- cated froma piece of sheetmetalwitha sabre saw. SeeFig.28fordimensions.

*

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Figure29.Cross-SectionalViewofSeated

LED

Holderin Console Cabinet

6. Placenew

LED

inLEDholderwith shorter (cathode) pigtailtowardsideconnectedto"Clear" switch(see Fig.30 and 31).Thisisimportant

—

indicatorcannotlightifcon-

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*m

^5.75-

M

I

2O 3 z 2

I

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I 0.26"

MATERIAL:

0.050'ALUMINUM OR STEEL

CATHODE(-)PIGTAIL SHORTER THAN ANODE

d ^- ₊ ^{/ j}

Figure30.PolarityMarkingon

LED

-»»j o.2rj-«-

T

Figure28.

LED

Replacement Tool

1.Unsolder the black and whiteleadwiresfrom "Clear"

switch terminals andunsoldertheyellow wirefrom the

LED

pigtail.Thisfreestheconsoletophalffor

LED

replacement.

2.Snipboth

LED

pigtailsoff closeto theLED.

3.Placeconsolecover,face up,on block anddriveoutold

LED

withsmallscrewdriveror 1/8-inch drift pin.

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+

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f¥

>

T>

<r_

/YELLOW WIRE

* n

_PLASTICPILLAR

(PARTOF CONSOLE CABINET)

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Figure31.IndicatorAssembly

12

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nectedwithreversed polarity.Usefabricated tool (Fig.28) to push

LED

intoholder.LED"clicks" into place.Anytool withoutashoulderusuallypushes

LED

out of theholder.

7.Formsnippedleadwires asshownin Fig.31and connect newLEDpigtailstothem. Solder quicklytopreventover- heatingLED.

8.Reconnectblack,whiteand yellowleadsfromPCboard tocompleteinstallation.

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TO PCBOARD

BLK. WHT

Figure32.Power-OnIndicatorWiring

CLOCK FREQUENCY ADJUSTMENT PROCEDURE

Incorrectclockfrequency adjustment causes pattern weave onscreen.Thisresultsfromabeatnotebetween thevertical syncrateofStudioIIand the

hum

frequencyinthe

TV

re- ceiver.Ifthe beatnoteismorethan 0.5 Hz, theweavebecomes noticeable tothecriticaluser.Clock frequencyisaslug adjusts menton thePCboard.

1 .

Connect scope probe tothejunctionoftworesistors as showninFig.34.Connect scope ground toRFshield,cartridge postortoothersuitableboard ground.

2.Adjust scope time basefor a totalsweeplength of20 millisecondsormore(syncon "Line") andverticalinput sensitivityforabout250

mV/cm

(0.625V/in).

3.Push "Clear" buttononconsoleandadjust slugslowly forzerowaveformdrift.SeeFig.33.Guardagainst overadjust- ment.

L, W

f

V1WWVWWWWL

(VERTICALSYNCINTERVAL) '

Figure33. WaveformUsed to Adjust Clock Frequency.

Scope Time-BaseLockedto60Hz PowerLine

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Figure34.Scope ConnectionsforAdjustingClock Frequency

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13

PC ^{Board Exchange}

EXCHANGE PLAN

DESCRIPTION

RCA

operatesaPCboardrefurbishing facility atSwannanoa, NorthCarolina.DefectivePCboardssenttothis facility are refurbished and returned to the sender^ata costof $1 5.00*

provided,of course, theexchange boardisrepairable.

PC

BOARD PACKING AND SHIPMENT

NOTE:Ifcustom shipping container described belowisnotavailable,packPCboardincushion of crumpled newspapersor"bubble pack"insuitably sized carton.Makesureboardiscompletelysur- roundedwith cushiontoprevent shippingdamage thatmightmakeboarduseless forexchange. Be sureto include acompleted questionnaire (from Page15) in thepackage.

1.PackdefectivePCboardinfoamshipping containeras shown. Noterelative positions ofPCboardcomponentsand

the molded-in supportsinthefoamplastic.Iftwohalves offoampackingfailto mateeasily, reverse relative position ofone to another.

2.Packfoamenclosurein carton.Use crumpled news-

^/

papersascushion aroundfoamenclosure.

3.Fillin allblanks onquestionnaire, particularlythose indicatingabnormalsymptoms(questionnairepacked with refurbishedboard).Pack completed questionnaire on outside of upper corrugatedfillerasshownand packin carton.

4.Include checkormoneyorderfor$15.00*.

A

refurbished PCboardwillbe shippedtothe addressyousupply on the questionnaire packed withdefectiveboard.

5.Ship prepaid(ParcelPostorUPS)to:

StudioIIPCBoard Refurb. Dept.

RCA

Distributor

&

SpecialProductsDiv.

Old Bee TreeRoad Swannanoa, North Carolina28778

*Price subject tochange withoutnotice.

^^

QUESTIONNAIRE

CRUMPLED NEWSPAPER

CORRUGATED BOARD

J

Figure35.PackingPCBoardinFoamContainer Figure36.PackingFoam PCBoard ContainerⁱⁿCarton

Studio

^II

Service Parts ^Kit

Serviceorganizationsdesiringto stockservicereplacement partsmayordera kitof StudioIIreplacementpartsand assemblies through

RCA

Parts Distributors asStock No.

199047. Costfortheentire kitis$99.95*

-

ascomparedwith a total of$122.90*forthe 20individual pieces.Thekit includes:

v

Quantity Description

2 PCBoard(lesscoaxial cable) 2 Coaxial Cable Assembly

1 SelectorSwitch Assembly

1 Power Supply Unit 3 Keyboard Assembly

Stock No.

742463¹ 2

742421 2

18V102 3

18V101 3

742458 ¹

Quantity Description Stock No.

Speaker 742448

LEDPowerIndicator (Incl. Holders)742461

"Clear" Switch 742459 Pushbuttonfor"Clear" Switch 742460 Set of 4 Console Rubber Feet 742462

1Includesreusableshipping cartonforeach board

*Price subjectto change withoutnotice.

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STUDIO

^IIPC

BOARD

1 Pleasepack completed questionnaireincontainer

1 (Pricesubjectto change withoutnotice.) <

1 Pleasedescribedefectsymptom(s).(Nodisplay,

1 partialdisplay,nosound,etc.)

EXCHANGE QUESTIONNAIRE

with defective board with check ormoneyorderfor$15.

StudioIISerialNn

RETURN

SHIPPING

LABEL

Firm

Name

Firm Address

Pity State Zip

Defect:Intermittent Continuous

' Note: Forin-warrantyboard exchange,include

| RCA Form PA737"Repair Report".

Attn:

J

STUDIO

^IIPC

BOARD EXCHANGE QUESTIONNAIRE

, Pleasepack completed questionnaireincontainer with defective board with check ormoneyorder for $15.

(Pricesubjectto change withoutnotice.) StudioI!SerialNo

| Pleasedescribedefectsymptom(s).(Nodisplay,

|

partial display,no sound,etc.)

RETURN

SHIPPING

LABEL

Firm

Name

Firm Address

City State 7ip

1

Defect: Intermittent Continuous Note:Forin-warrantyboard exchange,include

| RCAFormPA737 "Repair Report".

Attn:

r

r*

Replacement Parts and Accessories

Description Stock No. Description Stock No.

PCBoard(lesscoaxial cable,packed Pushbuttonfor"Clear" Switch 742460

inreusableshippingcarton) 742463 Rubber Feet (Packageof 4) 742462

CableAssembly 742421 "TesterI"TestCartridge² 5009339

Power Unit Assembly(incl.cordandplug) 18V101 Power Unit(forusewith"Testei1") 5008333

SelectorSwitchAssembly 18V102 Console Housing,Upper Half (Dwg. No. 1809952)

Keyboard Assembly 742458 Console Housing,LowerHalf (Dwg. No. 1809951)

Speaker,2.24-inchdiameter 742448 ^DressPlate(LEDIndicatorand^''Clear"button)

LED

Indicator(incl.plastic holder) 742461 (Dwg. No. 1808321-1)

"Clear"Switch 742459 ^DressPlate("StudioII") (Dwg. No. 1808319-1)

2RequiresspecialpowerunitStock No.5008333

15

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RCA

|DistributorandSpecialProducts Division|DeptfordNJ08096 Tmk(s)® Marca(s) Registrada(s)

PrintedinU.S.A. 11/77

Form 3E4589

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