Fisher FM-190 User manual

Service Manual
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FM-190 X-190

CAUT ION: This is a FISH ER precision high-fidelity in-
strument.It should be serviced only by qualified personnel -
trained in the repair of transistor equipment and printed circuitry.
EQUIPMENT AND TOOLS NEEDED
The following are needed to completely test and align modern high-fidelity instruments
such as amplifiers, tuners and receivers.
Miscellaneous
Adjustable-line-Voltage Transformer or
line-voltage regulator
Load Resistors (2) -8-ohm, 50-watt (or higher)
Stereo source (Turntable with stereo cartridge
or Tape Deck)
Speakers (2) Full-range, for listening tests
Soldering iron (with small-diameter tip).
Fully insulated from power line.
Test Instruments
Vacuum-Tube Voltohmmeter DC VTVM
Audio (AC) Vacuum-Tube Voltmeter (AC VTVM)
Oscilloscope (Flat to lOOkc minimum)
Audio (Sine-wave) Generator
Intermodu lat ion AnaIyzer
Sweep (FM) Generator (88 to 108 mc)
Marker Generator
Multiplex Generator(preferably with RF output-
FISHER Model 300 or equal).
Many of the items below are included just as a re-
minder-they are normal procedures,for experienced
technicians. Shortcuts can be taken but often they
cause additional damage - to transistors, circuit com-
ponents or the printed-circuit board.
Soldering-A well-tinned, hot, clean soldering iron tip
will make it easier to solder without damage to the
printed-circuit board or the many many circuit com-
ponents mounted on it.It is not the wattage of the
iron that counts - it is the heat available at the tip.
Low-wattage soldering irpns will often take too long to
heat a connection - pigtail leads willget too hot and
damage the part.Too much heat, applied too long, will
damage the printed-circuit board. Some 50-watt irons
reach temperatures of 1,000°F- others will hardly
melt solder. Small·diameter tips should be used for
single solder connections -larger pyramid and chisel
tips are needed forlarger areas.' '
• When removing defective resistors, capacitors, etc.,
the leads should be cut as close to the body of the
circuit component as possible.(If the part is not being
returned for in-warranty factory replacement it maybe
cut in half - with diagonal-cutting pliers -to make
removaleasier.)
• Special de-soldering tiplets are made for unsolder-
ing multiple-terminal units like IF transformers and
electrolytic capacitors. By unsoldering all terminals at
the same time the part can be, removed with little
chance of breaking the printed-circuit board.
• Always disconnect the chassis from the power line
when soldering. Turning the power switch OFF is not
enough. Power-line leakage paths, through the heating
element, can destroy transistors.
Transistors-Never attempt to do any work on the
transistor amplifiers without first disconnecting the
-~AC-power linecord - wait until the power supply filter-
capacitors have discharged.
• Guard against shorts - it takes only an instant for
a base-to-collector short to destroy that transistor and
possibly others direct-coupled to it.[In the time it
takes for a dropped machine screw, washer or even
the screwdriverrto glance off a pair of socket terminals
(or betweena terminal and the chassis)a transistor
can be rllined.]
• DO NOT bias the base of any transistor to, or near,
the samevoltage appl ied to itscollector.
• DO NOT use an ohmmeter for testi ng transistors.
The voltage applied through the test probes may be
higher than the base-emitter breakdown voltage of the
transistor.
Output Stage and Driver-Replacements for output
and driver transistors, if necessary,must be made from
the same beta group as the original type.The beta
group is indicated by a colored dot on the mounting
flange of the transistor. Be sure toinclude this in-
formation, when ordering replacement transistors.
• If one output transistor burns out (open or shorts),
always remove all output transistors in that channel
and check the bias adjustment, the control and other
parts in the network with an ohmmeter before insert-
ing a new transistor. All output transistors in one
channel will be destroyed if the base-biasing circuit
is open on the emitter end.
• When mounting a' replacement power transistor be
sure the bottom of the flange, the mica insulator and
the surface of the heat sink are free of foreign matter.
Dust and grit can prelent perfect contact. This re-
duces heat transfer to the heat sink. Metallic particles
can puncture the insulator and cause shorts - ruining
the transistor.
• Silicone grease must be used between the transist-
or and the mica insulator and between the mica and
the heat sink for best heat conduction. Heat is the
grea,test enemy of electronic equipment.It can shorten
the life of transistors, capacitors and resistors. (Use
Dow-Corning DC-3 or C20194 or equivalent compounds
made for power transistor heat conduction.)
• Use care when making connections to speakers and
output terminals. Any frayed wire ends can cause
shorts that may burn out the output transistors - they
are direct-coupled to the speakers.There is no output
transformer - nothing to limit current through the tran-
sistors except the fuses. To reduce the possibility of
shorts at the speakers, lugs should be used on the
exposed ends -at lea,st the ends of the stranded wires
should be tinned to prevent frayed wire ends. The
current in the speakers and output circuitry:is quite
high. Any poor contact or small-size wire,:,~~n cause
power losses in the speaker system. Use 14 ojl16 AWG
for long runs of speaker-connecting wiring.
DC-Voltage Measurements-These basic tests of the
transistor circuitry are made without the signal gener-
ator. Without any signal input measure the circuit volt-
ages -as indicated on the schematic. The voltage
difference between the base and the emitter should
be in the millivolt range -a sensitive DC meter is
needed for these readings. A low-voltage range of 1volt,
full scale - or lower - is needed.
Audio-Voltage (gain) Measurements-The schematic
and printed-circuit board layout diagrams are used.
Input signals are injected at the proper points - found
most quickly by using layout of the printed-circuit
board instead of the schematic. An AUDIO (AC) VTVM
connected to the test points should indicate voltages
close tothose values shown in the boxes on the sche-
matic.Many ot the signallevels in the input stages
are only a few millivolts-they can not be read on the
AC ranges supplied on most Vacuum-Tube AC/DC Volt·
ohml'eters VTVMs). Even with a l-volt range a signal
level of 100 millivolts (.1 volt) will be the first 1/10
of themeter scale. A reading of 1 millivolt (.001 volt)
willhardly even move the meter needle. '

DIAL STRINGING PROCEDURE
• Hook one end of the spring over the bottom eor in the
front••nd drive-drum (with the drum rotated to its extreme
counterclockwise position).
• Stretch the tension spring until the loop on the free end
sticks out of the s lot in the edge of the drive-drum. Now
Insert a length of stiff wire, about l-inch long (0 piece of
straightened-outpaper clip willdo nicely) through the loop
.to keep the spring stretched while stringing the dial cord.
Place the piece of stiff wire in the outer groove of the
drive-drumi bridging the slot in the drive·drum.
• Tie a small, non-slip, loop in the end of the dial cord.
i Thread the loop in the dialcord through the opening in
the driveo/lrum slot, under the spring, and hook the loop
over the top ear inside the drive drum.
• Wrap the dial cord around the clrive-drum (counterclock-
wise) about * of a turn, in the inner groove, ond then around
the top guide pulley.
• Stretch the dial cord to the left end of the dial, around
th.nwo guide pulleys and then back to the fly-wheel drive
shaft.
• Wind 3 full turns of dial cord around the.drive shaft (as
shown in the upper detail drawing).
• While keeping th" dial cord taut rotate the drive-drum to
TOINNEA~
GROOVE
o
TO OUTER
GROOVE
its extreme clockwise position and fit the clioIcorcl into
the remaining pulley.
• Set the dial cord in the outer groove of the front-end drive-
drum and thread it through the loop in the end of the tension
spring. (See detaildrawing.ot lower right.)
• Pull all slack dial cord through the loop in the tension
spring •
• Check all pulleys for proper threading of the dial cord.
• Tie a small knot in the dial cord to secure it to the loop
in the tension spring. (Use a tweezer with a small tip to
help tie the knot.) Keep dial cord as tout as possible while
tying the knot.
• Apply a drop of quick-drying cement to the knot to prevent
it from slipping or becoming undone.
• After the cement has dried completely pull out the piece
of stiff wire and gentlylet the spring contract t9~Q.pplytension
to the dial cord. ...':'
. . :~.
• Rotat. the front·end drive-drum ta its extreme'tbunter-
clockwise position.
• Set the clial pointer to the zero (0) calibration on the log-
ging seale of the s Iide ••.uIe cliol.
• Attach.the pointer to the dial cord and cement it in place
with a drop or two of quick.dryin,ll cement.
If replacement parts are out of stock, locally, they may be obtained
directly from the Parts Department of FIStlER Radio Corporation.
They will be shipped "best way", either prepaid or C.O.D. unless
otherwise specified.
For instrument-operation information and technical assistance write
Richard Hamilton, Customer Service Department,FISHER Radio
Corporation,Long Island City, NewYork 11101.

TROUBLESHOOTING GUIDE
When 0 defect occurs in On electronic circuit the first
component suspected is usually the vacuum tube. Many of
the inexpensive tube testers will not indicate all the possible
~ internal faults in a voeuum tube - sli ght defects often sneak
past these testers. It is better to substituteanother tube of
the same type.
Sometimes j tis possi bleto swi tch (transpose) tubes from
one circuit to another. This .method of testing is most suitable
when testing an individual stereo channel. When a good tube
is switched with 0 defective One of the SOme type the symptom
will be'ransferred from one stereo channel to the other.
When substituting tubes itis absolutely necessary to be
certain the tube being inserted is ·good - a new tube, from a
fresh Iy opened carton, is not necessari Iy a perfect tube. De-
fects ",an occur from shipping and handling.
If you have any doubts about the quality of a tubetry it
in an identical'eircuit that is operating properly. For example,
a tube with heoter-eathode leakage may operate normally in a
circuit with its cathode grounded; transpOSe (switch) it with
One in a circuit thathas a cathode-bias resistor and it will
cause a lotof hum.
•AC-interloek plug and ,..,eket, power cord and plug. wall outlet.
•Automatic shut~ff switch 51 (partof SELECTOR switch)
•Power switch 54.
•Automatic shut-off switch 51(partof SELECTOR switch).
•J9 and its plug and theinterconnecting cable and theturntableswitch on the
record player.
Distortion
Hum, Weak or
No oudio output Check: •SPKR switch position and its operation.
Test or.substituteVI. Test for proper DC voltages at: CR2, C2, R3; R3,R6,C3B; R6, R7, C3C;
R7, C3D.
•Setting of HUM ADJUST CONTROL (R2).
•29S-volt DC 'power supply fi Iter (C3A, B, C, 0 ),
•Bios supply (CR3 andC4) forAC ripple.
DistortIon
Hum, Weak or
No 'Cudiaoutput
(LEFT ehonnel only) SELECTOR In PHONO nod FM positions.
•Removeplug from Ll;FT RCRDR OUT jock, if used.
Test (filament leakage for hum) Or substitute VI, V4, VS.
Hum or
No audio output (RIGHTchannel only) SELECTOR in PHONOand FM positions.
•Remove plug from RIGHT RCRDR OUT jock, if used.
Test (fi lament leokage forhum) or substitute VI, V4, V5.
Hum or SELECTOR in PHONO positionsonly
No audio output •J3, J7, J9 and their plugsand interconnecting cables to therecord player.
•Clean and tighten oil ground connections. .
•ReverseAC line-card plug in wall outlet
•Reverse AC line-eord plug from record player in J18 (on chassis) if used.
Hum or
No audio outputSELECTOR inFM position only.
•Try other stations
•Reverse AC line.cord plugin wall outlet.
Check: • Antenna connectionsand antenna (outdoor)
Test (filament leakage for hum) orsubstitute Vll, V12, V13, V14.
Hum-
No audio output
Distortion Check: • Balanced modulator0401 and C409, C410; C407,
C412i L401, L402.
Test (filament leakage for hum) or substituteV401, V402. .
•IS. V402, C406, R433, R434, R43S, CR402, CR401.
•Ali9nment of Z421.

11131-2 MULTIPLEX e PRINTED CIRCUIT
IT
IR
------,
C412
470
(JJ
12K MPX
~GENERATOR.
180
1
r---~
I
_J
IA
I ALIGNMENT INSTRUCTIONS e MULTIPLEX SECTION I
ALTERNATE ALIGNMENT PROCEDURE
Formultiplex generator. without an RFoutput
Thepr.f.rred aHgnmentprocedure, in table1below, u•••amultiplex Slen.rator with, an RF output, lik.the
FISHER Model300. Optiml:lm performancewill b. obtained onlywhenthemultiplex decoder I. connectedto
theFM detector withwhich it willb.used.CheckIFalignment ~irst-poor alignmentcanpreventproper multi-
plex decoder operation.
When uling this alignment procedure, it i. nec.uary todisconnecttheratio detectorfromthe multiplex decoder
ot thepointwherethe oenerator i. connected. Unsold.r point1T carefully.Thegenerator inputmust b. through
asimpl.low-pass f1l••r-o12 K resistor betweenthe multipl." generator and theMPX input with G 180 pF .capa.
citorfrom theMPXinput endof ther•• istorto ground (Figure2, onschematic).
TESTEQUIPMENTREQUIRED: MULTIPLEX GENERATOR,AUDIO(AC) VTVM, 100 kC OSCILLOSCOPE WITHEX.
TERNALSWEEP JACKS,ALIGNMENT TOOL.
TAILI Z
TEST EQUIPMENT REQUIRED:MULTIPLEX GENERATOR, AUDIO <AC)VTVM. 100 kC OSCILLOSCOPE WITH EX·
TERNAL SWEEP JACKS,ALIGNMENT TOOL.
TAIU 1
GENIIATORINDICATORALIGNMENT
IUPS
CONN_CTIONAUDIO
UVIL
TV" AND ADJUSTINDICATION
CONNICTION
CompOSiteoutput of19 kc pilot
100 mV RMS
1
MPX generator toAC,VTVM 21 top Q~d bottom Maximum reading on VTVM
dem:cfvI~T~fr ~ti1nt1) only
(2S0 MV poP) to TP 0421
19 kc outptJt ofo:c~tl~~~~u:sn~ro~: ~':~-~~~b\~gto
2
generator to 01c1l10-Oscilloscopevertkol
Scopehorizontal Inputl
---
---
Input to TP 422
ZZ 38 kc.llSioloulpattern [see figurelJ
generator not etlnnectedshould beasslow-
toMPX settlon moving aspo"lble.
AC VfVM and oscilloscope
3
SaM. 01 Step I
1000 cpson 0.7 V RMS vertlc:ol Input to left
ZI top Maximum reoding on VTVMl clean
leftdlannel only 13.92 V p·P} l:nonnel output lug1000 cps linewave on os,IUoS'ope
{f.rmlnal Jill
4
Sam.a.Step I
1000 cps on0.7 V~MS Somea$Step 3 MPX leparatlonMlnl~ul~~~~atJn3b 0be~~~~~~~d be
right ehann.1only (3.92 VP'Pl <:ontrol (R4~.obtained In Step 3
VTVM (llid oscillos,op.SomeVTVM reading
Q' obtaln.d in
5
SamealStep 1
SamealStep40.7 V RMS ••.••rticell Input to rlahl
13.92 V poP) ehonnal outputlug
---
Step 3 : :: 2 db;clean1000 cpssine
{terminal lSI way.on (ncilioitope
6
JOOOcpson 0.7 V RMSMPX separation M~:i~ul~~3~n1 °be~~~~~d
SameasStep I I.ft chonnel only (3.92 V p·P) Sam.e05Step 5 control (R41.
ifneceualY- obtaInedin Step 5.
GENEIATORINDICATOR ALIGNMENT
ITIPS
IF
TY" AND
CONN.etION MODULAtiON DIVIATIONCONHleTlON ADJUST
INDICATION
1
MUI~rl:t=r::tor 19~rvlfot
±7.5 kc VTVMto TP~21 21 top and Maximum readIng: on VTVM
onte.nna terminal,bottom
19kc outJIut of Verti<:Qllnput of osc lIo- 0:c1'1~:a;u:sndC:Z ~r:~.~~ ~II;gto
2generator te osdllo·
KOP'horizontal Inpvtl
---
---
scopeto A.22; set oscillo- ZZ 38 kc. lInaiouspattern (see figure11
generotor not c:ol'll'l.cf,dscopefor ell:ternol Iweepshould beas slow·
to MPX I.dlon moving en possible.
Compo'1te MPX,VTVM and osdllolcope
~o«J~~:n.r~:C:~~eO:n~~{o~~~~~ 3
vertical input to righT
Sa~asStep I 1000 r;plon±75kc .channel OIJlputlugZI top
leftr;hann.1only[termlnal1RI
4CompositeMPXr Same asStep3MPX separation Mlnl:;U{;:a~~03dJIt£ 0be~Z~~~rnu~d be
SomeasStep1 1000 cpson
±7S kr; control (R-4'·
right channel only obtained InStep3
VTVM and OIcilloteopeSameVlVM reading atobtained In
5
SameasSt~p 1
SameasStep4±75 kc verticalinputtolrlght
---
Step3 ±:2db l clean 1000 cps sin.
channel output lug waveon oscilloscope
(terminal IS)
6
CompositeMPX;MPX separation M~:I;U;:a~~(ltJ"3b °be~~~fn~d
Same asStep'11000 cpson·±75 kc Same01Step 5 control {R41.
left dlaMel onlyif nec.nary-obtained In Steps.

.,I
lOOk.'
I
I
I
L _
-
81 SELECTOR SWITCH
I
OFF-SHOWN IN
•
FM MONO
•
M STEREO
•
FlI STEREO F1LTEIt
.~
I.1'0111ALl..VOLTAtMID (:UMINT
MtASUltEM NT In L.IM VOLTAGI
T01l1VAC.
t. DC VOLT"'E MIAIUftitl· WITH DC \lTV"
TO ~eI S 'ltITH NO atONAL INPUT .
lIl.lCTOfl •• ITCK IN ·'M MONO' 'OIITION.
"
TUIlt1l
,"OWlR
COMNECTOR

1.9" tolerance·for all fixed capacitor., un Ie•• otherwl••
noted Or marked GMV (guaronf•• dminimum value). All
capac-Itonnot marked uF are pF(uuF).
Symbol Oe.crlption
ClM.ldo<l •• 01uF.20l1. 600V
C2 EI•• ,..lyll ••100uF. 250V
C3 EI.ctrolytrc,4-Sectlon
A-l00uF.250V
B- 40uF. 350V
C- 200uF. 350V
0- 20uF,350V
C4
C5
C6.7
ca. 9
Cl0.11
C12,13
C14.15
C16.17
C18.19
C20.21
C22.23
C2d
Electrolytic, 8uF, SOY
Mylar, .047uF, 2S0V
Ce;romh:, 33,N7S0,l000V
C•• oml •• 3900. 1000V
C.ramlc,2200, lOOOV
Ceramic, 1800,1000V
Ceramic,68, N2200,lOOOV
C••• ml•• ,02uF.20l1.500V
C.ramlc,39, N1S00,1000V
Mylar, .022uF, 400V
.Mylar. ,012uF.250V
M.ld.d, .0TvF.20l1.600V
C.629·138
C50197·52
C5~0015
C50072-34
C5OO72·5
C5007208
C5OO70012
C5OO89·5
C50070017
C50197.28
C50197-49
C2747
PortNch
C2747
C50180015
C50180058
In ohm., 5" tolerance, 1/3·W unI••• otherwl•• noted.R20 Pot.,SOOK, Balance Control R501600137
K=Kilohm., M=Me;ohm •• R21A,BPot.,SOOK,Dual,VolumeControl R501600139
5ymbol De-erlptlon Part Mo.R22.23 Dep.Carbon. 22KR33DC223J
RI C.mposltlon.820K. 10%, ~W RC20BF824K R2d,25 Dep.Car~on, 47KR33DC473J
R2 Pot., Wir.wound, 500,Hum Adj. R516·128 R26,27 D.p. Carbon, 3901('R33DC394J
R3 Compo.'tlon,1.6K, 11m, lWRC30BFl52KR28,29 D.p. Carbon,1KR33DC102J
R4 Compo,ltlon, 270K,
JoIw
RC20BF274J R30, 31 Oep. Carbon, 220 R33DC221J
R5 Composition, 470K,
JoIw RC20llF474J R32.33Oep.,Carbon,47KR33DC474J
R6Compo.itlon, 1.8K, 10",
}iW
RC20BF182K R34.35Compo.ltlon,lS0K,10%,KW RC20IlFl54K
R7 C.mp •• ltl.n.3.3K. 10". ~W RC20BF332K R36A.B POL, lOOK,Duol~AC Balance RI078·116·
R8,9D.p.Carbon, 820K R33DC824JR37. 38.
RIO,11Dep.Carbon, 8.2M R33DC825J 39,'40 Dep. Carbon,1MR33DC105J
R12.13 Compo.ltlon,18M,10%,y'W RC20IlFl86K Rdl •.42,
RId. 15 Dep.Carbon, 1K R33DC102J 43.44 Oep.Corbon, 1K R33DC102J
R16.17Dep.Carbon, lOOK R33DC104J R45, d6 D.p,Corbon. 6.8KR33DC682J
Rl8A, B.R47.48 Composition,100, 10%,lWRC30lFl01K
19.,B'Pot., SOOK,Dual, Ba••, Tr.bleR50160013.8Rd9,50Wlrewound,50,10%,SW R556·142
Symbol De.crlptlon Part No.PC1,2Printed Circuit,·ToneControl PC50187-9
51Switch, S.lector .51078-112
CR1.2 Olod., SiliconRectifier5R5047252,3Switch, Slide550200.5
CR3Diode,Silicon RecflflerV·1112Tl Trondormer, PowerTlO78-115
11PII.t Bulb.#1847 150009·1T2Tron.former, OutputTlO78-11M
JllPhono'.JockJ846·120·1 T3 Transformer, OutputTl078-117·1
If replacement parts are outof stock, locally, they may be obtained
directly from the PartsDepartment of FISHER Radio Corporation.
They will be shipped "best way", either prepaid or C.O.D.unless
otherwise specified.
Forinstrument-operation information and technicalassistance write
Richard Hamilton,Customer Service Department, FISHER Radio
Corporation, Long Island City, NewYork 11101..
CAPACITORS
'0" tolerancefor all fixed capacitor.,unle ••oth.rwl.eC17C•• oml.,5000. +80 -29". 500V C5008906.
notedor mark.d GMV (guarante.d minimum volue),All
capacitorsnotmarked uF are ·pF (uuF).C18 Ceramic, 2700,lOOQV ·C50072.17
C19C•• aml •• 5000 •.+80·-20l1,SOOV C5i1089-6
Symbol Deecrlption Port Ho.C20C••• ml••. 02uF.GMV.1000V C50071-6
.Cl C.romlc, 21,5%, N7S0, 1000V C50070032C21Electrolytic,2.S.ctlonC50180076
C2Ceramic, 1000, GMV,tOOOV C5OO7lo2A- 40uF, 350V
C3 Ceramic, F••dthru, 1000 GMV C592·187B- 20uF.350V
C4 Ceramic, 8, ±;SpF, NPO,500V CC2OCJ080D5 C22 Ceramic, 5000, +80
-2<m, SOOV QOOS9-6
C5 C.roml •• 10. ±.5pF, Nl50. 500V CC20PJl 0005C23Ceramic·,2700,10aGv C5OO72.17
C6.1 C.ramic~Trimmer C662.123 C24Ceramic, 5000. +80 -20%, SOOV C50089-6
C8.,BVariable,FMC818·116C25 C.raml ••2700, 1000V C50072·17
C9C•••ml•• 8. ±.5pF. NPO. 500V CC20CJ080D5C26C.ra.II ••5000. +80 -20l1.500V CSOOSU
Cl0 Ceramic, 1000, GMV, 1000V C5007lo2C27,28.
CII C.ramlc, 33, 5%,N750,l000V C50070025 29Ceramic,330,1000V C50072·1
cn Ceramic, 24, 5%, N150,100DV C5007008C30Electrolytic, SuF,SOV.C629·128
C13C.ramlc, 47, 5%1N760, 1000V C50070.29 C31.32
C14C.,.ml •• 100,5%. N1500.1000V C5007001933 C.,amle.5000.+80 -20l1, 500V C50089-6
CU Ceramic, F•• dthru, 1000, GMV C592·187 C34C••• mle. 560. TOOOV C$OO72·14
C16Ceromlc,1000, 1000V C50072.3C35C.ramlc,5000,+80 -20%, 500V C5008904
Composition,In ohms, 10% tolerance,.Y. Wau, unle ••
oth.rwl,. not.d. K=Kllohm, M=Mtgohm.
SymbolD••crlptfon
Rl.2 lOOK
R3470
R4820
R5150K
R6,7 lK
R8T50
R9 21K
RIO lOOK
RlllK
R12GI••••3.3K. TOll, 7W
R13
Rid
RU
R16
R17
R18
R19
R20
R21
R22
R23
R24
R25
R26,27
Part No.
RC20BF10dK
RC20llF471K
RC20BF821K
RC20BFI54K
RC20BF101K
:mmm
RC20IFl04K
RC20BF102K
RPG7W332K
GI••••560. lOll,3W
150
47K
IK
47K
56K
lK
270
UK
lK
T5K
4.7M
Dep.Carbon',470K,~", l/aW
Dep. Carbon,330K, 5", 1/SW
RPG3W561K'
RC20IlF151K
RC20IF473K
RC20lFl02K
RC20IlF473K
RC201'563K
RC20BP102K
RC201lF271K
RC20llFU2K
RC20IlFr02K
RC20BFl53K
RC20llF475K
R12DC47dJ
R12D.C334J
Symbol
11,2
13
Ll
L2
L3
L4
L5
Deacrlptlon
Lamp #1847
5t.reo Scan IndicatOf
Coli,FM Ant.nna
Choke ·1.5 Mlcrohenry
Choke, RF
C.II. FM RF
,Coil, FM Oscillator
Part No.
150009.7
1501621·2
L818·1l3
L500660d
L629·180
L818-1l4
.5818.118
Choice, .68 Mlcrohenry
Choice, .~Mlcroh.nr,
Choke, 3.3 Mlcrohenry
Switch, Selector
Tranlform.'1FM IF
Transformer,FM IF
Coil, Limiter
Tran.,forme"Rdlo D.t.ctor
L50066·1
L50066·21
L50066 ••
SI194A113
ZZ662.117
%%2981
%%5021006
%%5.021009

r
I
I
I
I
r~---·
I
I
I
I
I
1
I
I
T.P.421
R428
lOOK
MPX
C408 R40SCONN.
.luF
10K TOFM OETECTOR
C407
I
HEAfERS
470
I
'---
R410 MONO OUTPUT
1M
I.
L401
I
LEFT OUTPUT
20mH
I RIGHT OUTPUT
1
180VIZOV
L402
I
I
120Y f05V
20mH
R411
I
I8llVf85V
1M
I
210V 20
TOALIGN-METER SWITCH
(NOTUSEO ON ALL MOOELS)
n@@A Il@@ @@I l@@
,.lile 101IF
,. lH 101
llC1L1MtH
,p
P811SICIIS IMOI"A4l2.
C401-C412
~~CR401-CR402 ~
L4Cl e L402
D401 .
VOLTAGES CAN VARY t20'Ilo
STEREO
MONO
I PARTS LIST
I
Symbol
D•• crlptl.oh PD,tHo.
Symbol
De.crlptlon
PartHa.
DESCRIPTION
C423
Poly.tv''''., 4700, 5", 12SV
CSOB634-21 R411 R.al.tor, C.p. Carbon, 1m, 5%, '/8W R12DC105J
C424 Poly.tyren.,220, 5"", SOOV
CSOB634-2 R412
R•• I.tor, D.". Carbon, 10k, 5%,
C42S Poly'styrene, 4700, 5%,12SV C50B634-21 I/SW'R12DC103J
Ail clrCl,Ilt c070nenti with.ymbol.btgl"nl~ with
C426 C.ramic, .02 uF, +80, _20%, SOOV
CsOOS9-4R421
D.p.Carban, 2.21,4, 5%; 1I3W
R33DC225J
.cOl Or. locat. on the prlnt.d·clleul, board; 0" be·
C427 Caramlc.2200, 301I, 1000VC5i83-10R422
Oep. Carbon, 10K, 5%, 1I3W
R33DC103J
ginning with ,042' at.mountedon themetal .ubehanl••
C428 Ceramic, 100, 20", l000V C5 83-9 ·R423
D.p.Carbon, lK, 5 , 1I3W R33DC102J
~APACITORS C429
Ceramic, 1200,10%, 1000V
C~ 83-S R424 Potet' tlometer,5K Separation
C430 C••• mlc, 68, 10" NPO,1000VC5 711,46
Con·trot
R5015o-11
M tolerancefor all fhced capaclt~.,unl.ss oth.rwls.
c;431
Mica, 4700,5", 300V.
CS0332-7 R42s
Cep.Carbon,3.9K, 57\.~1/3W
R33DC392J
C432 C.ramlc,5000,20", SOOV
CSOOS9-1R426
ComPosition, 10M, 10"", 1I2W
RC20BF106K
no,.d·or mark.d GMV (guaranteed minimum volw).
C433 Ceroml~, 39, 10", H1500, 1000V
CS007O-17 11427 Dap. Carbon, 23OK,511,1I3W R33DC224J
MPX 120
All capacitor. not marked uF ar.pF (uuf).
R428 Dap.Co.bon, lOOKR12DC104J
Symbol
D••crlptlon PortNo.
RESISTORS R429 Dep.Ca.bon, 1.5M, 511,
1/3W R33DC15sJ
Symbol
Description PartHo.
R430 Dep. C••bon,47K, 5", 1I3W R33DC473J
IND1CA:TOa
C401
Capacitor,Mylar, .047uF 10% loDV
CS08574·s R431
D.p.Corbon, 68K
R12DC6S3J
AMPLIfiER
C402
C~pacltor, Polystyren., 2700 5"
R401 Re.lstor, Dep. Carbon, 33k5",
R432 Dap.Ca.bon, ISO, slI,1I3W R33DC151JAND
3llKC
12~V
C50B634-201/8W Rl~pC333JR433.434,
OSCILLATOR
C4Q3
Capacitor,Plastic Film, .1uF
R402
Reststor,Dep.Corbon,1.5m,5",
435
Composition, 33K, 10%, lW
RC30BF333K
I Z422 I el·
Z421
I e~:~~I~~~R
20" 2SOV C50B633·1 1I3W R33DC155J
C404 Capacitor, C.r. Disc., 1500, 10"
CSOBS76-4R403
Resistor, Compo.ltlon, 22M~10",~W RC20BF2~6K
MISCELLANEOUS
C405
Capacitor, Pla.tlcFllm, 1uF 20"
R404
Resistor, Dep.Carbon, 470k;S",
·2SOVCSOB633·1I/SW R12DC474JSymbol
D.ser I'ptlon Part Ne. ECC81 ECC83
C406
Capacitor, Plastic Film; .033uF
R40S
Re.i.tor, D.p.Carbon, 470k, 5",
CR401
Dlod.
Vl1'1W 12AT7 12AX7
2OlI400V CS08633·3O 1I8W Rl2DC474JCR402
Dtod.
V50A26Q.15
C407
Capacitor, C.r.Disc, 470pF .1~
CsOBS76·1R4.06
R•• lstor, D.p.Carbon, 470k,S",
CR421
Diode V1l12
C408
Capacitor, Plostlc 'Ftlm,.luF 20"
1I8W RI2DC224J D401
Ring Demodul~r
V50A26o-18
2SOV C50B633·1R407
R.sistor, o.p.Corbon, 22k, 5",
L401
Coil
L50334-2
~09
Capacitor, CAr. Disc,820 10" C50BS 76-3l/SW R12DC223J 1.402 ColiL50334·2
C410
Capacitor, Cer.Disc,820 10%
CSOB576·3 R408
R.slstor,Dep. Carbon, 22k. 5",
L421
Coli, 20uH Ls0334·2
C411
Copacltor, Pla·•.• lc· F·i1rn, .1i.1F 2OlJ'
·l/sW Rl~DC223J 1421
Tronsformer, 19 kc:
ZZS0210034
2SOV CSOB633-1 R409
R.sl.tor, o.p.Carbon, 10k, 5%,
1422
T.ransformer, 381cc
ZZ502100S4
C412 Capocltor, C.r.Disc,470pF,10"
CSOBS76·1I/SW R12DC103J
Printed Circuit Bd. PB1'131B111
C421 Mylar,.•027 uF,511.IOGV C50B57406R4io
Re.lstor, Dep. Corbon,1m, 5", MinI.Pin Term. A50A577
C422
Poly~tyren., 18~, 5", SOOV CsOB634-1lISW R12DCIOsJ
51.evlng 23--32" Lg.
E~OA684-4
.. _.-' -'-", "._', .~~ -',:-'-- .._- ._._-'.

8ALANCE
CONTROi.
~:~
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r~~
3901<
.,. ...
'.,1<
ca •
N.
•OUUF
'"
••
,
*.OOV
,,8f€2
It".•.
'"
lOOK
~.""
lAC BA"
mJ
"
[E]
...
IPHONO
"
~
..
OUT
S2B
I HIGH FILTER SW I
OFF
r---....,
I 1201C 750 I III
8AS,,- L-L1t- I '17
.......... .J .02UF
"'8a [ IIII'B RuI
••" J L~ ••,
r·
CI5llF
l TREBLE
I 21k3000 I
L.:: J
PC2
NOTe::
I, ALL VQL1lI4ES MEASUR£O WITH 'VTVM
AT I nV.ACI.lfl£. NOSl6NAI.INPUT
2.*VOLTAGf 'VAlIIlr:J WITH AU
S. ALLcall'AOTOIl: 1 NOT MARKEDAIl:E PI" lUUFJ
4.VOI..T.AQES .M£ASlRt£O WITH TUNER OFF ANO
WU O Cfl£"'E SLIGNTLY WITH TUN[R ON
PoS SfSELECTORSW
I PHONO - SHOWNIN
2 FM
3 AUX

I ALIGNMENT INSTRUCTIONS I
iet the SEL.ECTOR switch to theMONO pOlitlon.
S.t tuning dial to tho extr.,melow-frequency pOlltlon.
.Dial pointer should lineup with the calibration mark
It thelow-froquoncy end of thedial scal •• ROlot tho
~ial pointer if necessary.)
Narm up the chauis andthe t•• t equipment forat loost
15 minutes.
Adjust linovoltage(power input to c:ha•• i•..) for 117 volt.
AC SO to 60 eye I•••
(Use only the proper, fully insulated,alignment tools.)
'Reduce signal generator output during alignment to k.ep
VTVM reodingbelowthatspecified for step 1.
Repoat steps 4 and 5 to obtain proper dial calibration
and maximum sensitivity.
STEP DIAL SIGNAL GENERATOR DC VTVM ADJUST INDICATION
GENERATOR FREQ.MOD.
COUPLING Tl;T2, T3,
Moxlmum negotl ve
I
Tut Point3*
T4,ond Ts valtog8
Unground.dtube
10.7 MC Nonetopand bottom (b_low 20 volt.)
S.t dial .hl.ldof V2
-
pointer for
extreme
Ho•.I.ud of DC VTVM
low·frequency
to TEST POINT 4.
position. GroundI.ad ofDC
2
Un5lround.d tub.
10.7 MC NoneVTVM to
i unctIon of T5 topZ.ro Indicationon
two •• rl•••.conn.ct.d
,hl.ldofV2eXf.mal r•• I'for •nro"c.nt.rdial.
.
(47K S%), wlr.d boo
~~d~o~~~:POINT3
±22.S KC
deviation Through lOOK
L5 and L4
390 MC 90MCo'
r.slstor to
400 co••
Tut Point 2
Two 120·ohm
±22.S KC
Adl"'t formaxi·
Through lOOK
mumn.gatl ••••
carbonresl.tond••••lationvoltog. and check
I
4106 MC
In•• rI•• with
106MC
r•• i,tor to
C7 ond C6
forsinusoidal
g~.rotorI.ocl.
0'
T.st Point 2
;
to theani.nno
400 e•.•••
wav.form,with
seop., otLEFT
t.rmlnals
±22.S KC
Through lOOK
or RIGHT outPl,It.
S
98 MC (Flour. l). 98 MC
d••••latlon r•• lstor to
Ll
0'
T.•• t Point 2
400ep ••
~
TEREOSCAN
I LAMP
R4
AND381<C ~ STEREO
OSCILLATOR SEPARATION
Z422
s
Z421 . C,NTROL
I9KC PILOT
r;1 ~ ~ ~ANDSIGNAL
LJ U LJ~ AMPLIFIER
ECC81ECC83
12AT7 12AX7
1ST 2ND 3RDIF
$ G $ [~:t@)~ G
EF94 Z2 6HS6 Z3 EF94 Z4
6AU6 6AU6
ECC8s8n ~
6AQ8 U
L-RFAMPZl
AND
OSe·MIX
RIGHTLEFT
~
OUTPUTS
I CHASSIS LAYOUT
• AMPLIFIER I
CHA:~~t6RIVER eHAN~~rTDRIVER LEFTANDRIGHT
..'INPUTAMP
O0
AND01NV ECC:QINV ~ECC83
'.:.J 12AX7V ~;2AX7
$~~99o.
INT sPKRS RIGHTPUSH·PULLLEFTPUSH·PULl :lo..
I r- 000-, I POWEROUT POWEROUT@@~~
RIGHT COM lEFT ELL80@ELL80@ l FM 1 FM J
6HU8 6HU8 RI~rT ~EI)T