Yamaha R-50 Service Manual

--

FRONT PANEL

I

STEREO RECEIVER

R-50

III

r--i---T-----=.;=-r--;---lF;;r:

l* ll

"ll

*

ll I

l l'!|!rE!GllE.

lt:t:iiiiili:iii.iillr.r.rrl

CONTENTS

I

TOSERVICEPERSONNEL

......1

SPECIFICATIONS. ._....1

PANEL

REAR

INTERNALVIEW.
DISASSEMBLYPROCEDURES.
ADJUSTMENTS

PRINTED

SCHEMATICDIAGRAM
BLOCKDIAGRAM
PARTSLTST.

..

.

. ......,

CIRCUIT BOARD

......3

,..

4-6

....9

......9

..10-19

2

3

7,8

SINCEI8'7

NIPPON

GAKKI

@YAMAHA

LTD. HAMAMATSU, JAPAN

CO.,

474

2.5k

83.3.

Printed

in

Japan

lll@

a

R-5()

TO

I

(Pr:epared

12701

service

Before

carefully

SERVICE

in accordance

of

this

read

PERSONNEL

with UL Standard

this

appliance

manual.

service

Please make Leakage-current

meter

are acceptably

before returning the

supply

to the

by

suitable

parts

circuit

customer.

AND USED

measurements

that exposed

from the

appliance

PROBE WITH SHIELDED

A

B SEPARATED

MEASURING CURRENTS

PART

OF

Confirm that

APPLIANCE

the leakage

TO ANOTHER.

current

than 0.5mA AC.

SPECIFICATIONS

I

please

you,

by

or Resistance

determine 1

to

insulated

LEAD.

AS

CLIP

FROM

not more

is

WHEN

ONE

LEAKAGE

GROUND

Appliance

Usable

30dB

Sonsitivity

Mono

CURRENT

intended

Ouietinq

(S/N

26dB)

MEASUREMENT ClRCUITS

for connection to a 1 20

75rl

(DlN)

0.8lrv
o.8pv

o.8pv

volt

(9.3dBf)

(9.3dBfl

(9.3dBfl

power

supply.

(G)(B)(A)

(G)(B)(A)

852

0.02%THD

17.5W8r}

Phono
Aux,Tape

Maximum

Output

Frequenry Response

RIAA

Total Harmonic

t ntermodulation

Tone Control CharactotistiG

lnput

Signal

l kHz 0.01%

Rec Out

0.015%
20Hz

Equalization Deviation

Phono

Phono

Aux,

to

Aux, Tape

Bass

Treble boost/cut

THD Phono 85mV

Level/lmpedance

THD

to 100kHz Aux,

Distortion

(lV)

to

Tape

SP

Distortion

(SmV

5.1kO

boost/cut

1W8o

Out

lnput Shorted)

Shorted

Tape

lkHz

1.8d8

2.5mYl47k{t

O.42mV

20mV

120mV/1ko

o59v1220a

-3dB

lo.sdB

0.015%

0.008%

88dB/80dB

60dB

(at

tlOdB

(at

tlodB

(G)

50Hz)

2okHzl

nal to

Mono

Mono
Stereo

Mono

Stereo

Harmonic Distortion

Stereo

tkHz o.1%

lkHz 0.15%

lkHz

l4OkHz

lkHz

to 15kHz

30Hz

US & Canadian Models

General Model

European Model

British &

Power Consumption

Australian

Models

Devl

85dB

(G)(B)(A)

(G}(B)(A)

SOdB

80dB

(G)(B)(A)

76dB

(G)

0.15%

4OdB

-1.5""

513 to 1620kHz
510 to 1620kHz

120V

AC,60Hz

110

120V

(U)(C)
(R)

ACl220

-

240V AC,50/60H2

22OV AC, SOHZ

240V AC,50Hz

180W

100w

(G)(A)(B)
or

-

Attenuation

FM 10O%mod lkHz

40kHz mod

FM

Mono

stereo

(at

-20d8

500mV/5ko

380mv/5ko

1

(15.3d8f)

1.6pV
(38.1dBfl

22sV

lkHz)

(G)

max.

Switched

Unswitched

200W
200W

max.

7-118x4x1

(Ul

U.S.A. model

.....

(C)

Canadian model

.....

(A)

..... Australian

(G)

European model

.....

(Bl

British model

.....

(Bl

General

.....

Specifications subject to change without notice.

model

model

REAR PANEL

I

v

U.S.A. & Canadian modets

v

General model

R-5()

ATTEilTloi:milo

r@

v

British

&

v

European model

Australian models

[o t20 eeo aao vcE

lmwAre solaoHz^,

rpto c fir co,uD.

@

+@-

-O+

@o

2

R-5(,

INTERNAT

r

VIEW

eowen

Q

ELEcrRoLYTrc

O
@otooe

@eu
@rnorur

tr tC:

@

@eowen
@nowen

@unrru

@uex
@urcno

@rururruc

TRANsFoRMER

U.S.A.
European model:

Australian

General

BRTDGE:

roor ANTENNA

END

ttPC577H

swrrcH

tc:

ctRcutr

lc: LA338o

coNPUTER rc:

& Canadian models:

& British

models:

model:

cAP.:

68oopF

s4vB2o or RB4O2or 4D4841

PAcK

E,Fl

STK-4873

BoARD

coNTRoLLER

(1)

LC65o2c-604

tc: LC721o

g

cA66400

GA66410
GA66420
GA66430
46V

DISASSEMBLY

r

*

Replacement

@Removing
@Removing

@Removing

of the

Top

Front Panel

Bottom Cover

parts

Cover.

PR.OCEDURES

of

almost circuit boards in this

Cup

. . .
. .

Screw

Binding

.

Screw

Head

3xB

Binding Head

Screw

3x8

4x8 FNM3-3g

Tapping

FCRM3-B[

Tapping

FCBM3-BQ

(Remove

unit

parts

possible

is

@

in order

by

Removing

r-o"r.

"

W

of disassembty

removing

Heat

Sink . .

@

p

the top

Pipe

as numbered.)

bottom

and

.

.

Binding Head

Screw

3x8 FCM3-BI

Fixture

cover.

Tapping

Fig. 1

Block

Heat Sink

Fig.2

3

ADJUSTMENTS

I

AUDIO SECTION>

power

the

supply

OF

voltage

switch

pushed

is

point

Test

+B-E

_B-E

+20-E
+12-E

+9-E

-9-E

+5.6

-

FB-E

AB-E

terminal

Speaker

pin

or

ol

5

(L

ch) and Pin 12

(R

ch)

on,

E

1C112

for

wait

Rating or standard

At FM
At AM
At FM
At AM

minutes before measuring,

5

+36V t

tsv

-36V

+20v t2v

+12.5V t

+O.sV

+9.5V

t0.5V

-8.9V

+5.6V t0.5V

reception mode'

t

+12V

reception mode

less than

reception

less than

reception mode

+

+12V

t50mV

OV

5V

lV

1V

+1V

+1

lV

mode

V

Make sure
comes within

be

to

sure

Adjustment

that AC

Models

AC

u-c 120V

?/i20v

G

A,B

240V

the most stable

of

method

line voltage

line voltase

t

10%

L,10%

+

10%

operation.

Rimark

load

No

<CONFIRMATTON

adjustment

Before

1: After

Note

Step

1

2

Confirmation

Power

DC offset

\l

<TUNER

oBefore

Note 1) After

Note
Note

ADJUSTMENT>

adjustment

the Power switch

minutes

most stable

2) Adjust

driver.

screw

not

3) Do

before

the

forget

pushed

is

measuring,

operation.

coil and

OSC

keep the bottom cover

to

IFT

on,wait

to be

sure

of

with a nonferrous

on.

for

the

o

5

SSG

AM SG

OSC

ACVM

Measu

FM SG

DIST. M

FC

ring inslruments

FM

signal

Stereo

AM

signal

Oscilloscope

Distortion meter

Frequency

volt meter

AC

generator

signal

generator

abbreviation

generator

counter

\-/

FM TUNER

1.

oUse

200H2

REC OUT.

.On

step

(J|0OO36

between TPI

Adiustment

Step

Detuned

1

confirmation

2

Discriminator

balance

ment

station

3

confirmation

Monaural

4

tion adiustment

4

SECTION

to lskHz

2 connect

1 and

or similar)

(S

OUT)

item

noise

adjust-

center set

distor-

bandpass

the auxiliary

in series

and TP2

Auxiliary

Connection

terminal

TPl

-TP2

(S

out)(NVcc)

FM

300s}

ANT

TP1

-TP2

(S

(NVcc)

out)

FM

300r}
ANT

REC OUT
(TP7,

TP8}

filter

to measure

center

the resistor 1OkO

with

(NVcc).

center

meter

tnstrument

Auxiliary

meter

FM

SG

[gguH,

(75.2dBr)

lzoosrr

IMONO

uoo

[roox

Auxiliary

meter

FM

SG

[98MHz

lzoaep l75.2dBtl I

I monaural 1 OOHz orl

1oo%

L+oon'

DIST. M. OSC

BPF

required

center

t

tttt,

lkHz

center

t

1t<Hz I

meter

MoD_.j

the

I

]

|

I

oSet

the switches

INPUT ....

BandSelect

TUNING/MODE ...

VOLUME . .

Adiustment

locations

T101

(ST

DIST}

T102

(DISCRI

CENTER}

TUNING

+UP

vc101

(MONO

or

SW

DOWI

DIST)

following

to the

TUNER

FM

..

AUTO

Min

Adiustment

Adjust
maximum at detuned

point.

Adjust
pointer

iary center

to

at detuned

0

Confirm that the auxil-

iary center
deflects to 0 at
the signal

Reduce distortion

minimum

method

noise level to

that

so

the

of the auxil-

meter

meter

of FM

points

point.

tuned

SG

to

positions.

Rating

standard

Less than

-64d8

or

Bemarks

Confirm

all signal O
indicators

lisht

that

Step

5

6

7

Adiustment

VCO

Stereo

confirmation

Separation

mation

Pilot

I

adlustment

I

10

11

adiustment

distortion

confir-

cancel

Discriminator

confirma'

balance

tion

.

adiust'

offset

lf

ment

search

Auto

reception
mation

confir-

item

Connection

terminal

FM

300s,

ANT

TPs

-TP6

(+12)

11gtvl)

TP4

TP3

-

(19kHz)

FM

300s,

ANT

OUT

REC
(TP7,

TP8)

FM

300s)

ANT

REC OUT
(TP7.

TP8)

FM

3000

ANT

OUT

REC

(TP7,

TP8)

Tfi

-TP2

(S

out)(NVcc)

300s,

ANT

300a

ANT

TEST

nals

(K4,

T6)

3000

ANT

tnstrument

FM SG

fgSMHzttt<Hz I

zoasp

I
I Unmodulated

hesistor

FC

(G)

FM

'98MHz

70dBp

STEREO

1kHz,

Dtsr-

BPF

FM SG,

lsst\rHi

zoaer,

I
I STEBEO

rtnz,

I

bsc,

FM

lg8MHz

zoaep

I

Lprlor

osc

ni.annnant RPF

Auxiliary

FM SG

FM

FM

l-98MHz

l-roac,

FM

[98MHztlkHz I

[zoaeu

FM

Short

FM

[9BMHz

lzoaar

I ruoNo

termi-

Irooga

(7s.2dBf)

2.2Mo

SSG

SG,

t

(75.2d8f)

100%

M, OSC

SSG

(7s.2dBf)

toox

acvNlt,

SG.

SG

SG

required

lkHz

L, R

MOD.I

f

ttl'{z

R

L or

rrltoo-l

ePr

SSG

t

1t<Hz

(75.2d8f)

MoD

9%

meter

cente

i

lkHz

t-15-2dBfll

(75.2d8f)

t

t tHz

l25.2dBtl

tgz

t

moo

I

-l

I
I

I

I

|

I

I

I

-l

-]

Adiustment

locations

VB102

(vco)

Stereo

tor

T101

(ST

VRl01

(PILOT

CANCEL}

I

VR103
(FM

TUNING

+UP

indica'

DIST)

FINE)

or

DOWN

Adiustment

Connect

O

2.2Mo

(i9M)

and
stereo

Adiust

@

frequency

Confirm

age

opposite

minimum

Observe

the

that

le\rel

minlmum

Confirm
auxiliary

points

signal

By
terminals,
shifts
adiust

lowest

comes

g8.0MHz-1*79

Confirm

SW

search

possible

ing

between

and

force

mode.

level

OSC

carrier

reduced

to 0

of

shorting

by

so

effective

to I

r-This

I

When

button.

method

resistor

TPs

(+12)

1p6

set

the

that

so

lgkHz

is at

the

that

the

of

channel

waveform

adjust

and

leakage

to

the

that

center

tuned

at

FM SG

TEST

counter

the

digit,

one

the

that

0.

or

-8O.O

shifting

auto

that

recePtion

the

with

in

VCo

leak-

is

meter

digit

figure

is

tun'

on

so

then

E

the

Rating
standard

19kHz

lOHz

Less

-48dB

model

G

only

than

Less

26dB

More

34dB

or

I

than

Less

-35dB

than

than

Bemarks

indi-

lights

adlust-

remove

and

FC

2.2MA

resistor.

adiust

when

,

within

is

it

lf

points to 0,

allover

start

step

from

adiust-

After

open

ing,
TEST

nals.

Confirm

muting

that

performed

is

at auto

that

not

termi-

recep-

Confirm

stereo

cator

up.

After

ing,

the

Not

T101

is

specifications.

tion.

2.

the

it

J

J

TUNER

2. AM

oConnect

Adjustment

Step

SensitivitY

1

mation

Sign'al

2

tor confirmation

Auto

3

AM

the

O

search

rqception
mation

SECTION

dummy

item

confir'

indica'

confir'

antenna

Connection

terminal

ANT

AM

OUT

BEC

(TP7,

TP8)

ANT

AM

ANT

AM

adiustment'

for

lnstrument

DST.

ACVM
AM

AM SG

l-1O8OkHz

fsoaar

AM

AM

[1 oSokHz

[ooaar

M

dummY

dummY

SG

required

antenna

t

0.1

antenna

i

0.1

kHzl

kHz

]

I

]

oWhen

FfU,

tH,

Adlustmenl

locations

PRESET

P1

P2
P3

PRESET

P3

Signal

TUNING

+UP

or

DOWN

the

once

frequency

tt',.

it memo;ied

Adiustment

Confirm

sensitivitY

Confirm

indicators

O

O

Confirm

SW

search

possible with

tunning

terminals

test

of 630kHz,

each

at

maftod

maximum

the

all

that

light.

auto

that

recePtion

the

button.

AM

signal

is

are

preset

Rating.or

$andard

less

55dB,r

shorted

1440kHz'

position

than

adjusting

in

-and

2 and

1'

Remarks

Confirm

all

indicators

goes out

detuned

point.

1080

signal

3'

that

O

at

J

DIGITAL

3.

Step

I

2

CONTROL

Adiu3tmont

memory

Preset

confirmation

channel

Last
memory

mation

confir-

itom

SECTION

Connection

terminal

FM

3000

ANT

AM ANT

!nstrument

FM SG

[98MHz

lzoaep 7s.2dBtl I

luoruo trxz I

Lroox

AM dummy
AM SG

[ro8orxz

lsodep I

L+ooxz,30%

required

i

lkHz I

rvroo

antenna

io.lkHzl

MoD

Adjustment

locations

FM/AM SW

TUNIT{G

MEMOBY SW

I

PHESET SW

l

POWER SW

SW

Adiustmont

Memoring

O

Pl at

SET
frequency.

Memoring

@

P2 at AM SG

SET

frequency.

Confirm

@

quency
recalled.

Press

O

Turn

@

off.

switch

After

@

seconds,

on.

switch

Confirm

@

PRESET

recalled.

is

method

PRE-

the

FM

SG

the PRE-

that the

memorized

the PRESET

power

the

about 5

turn the

power

that the

Fl memorized

O

fre-

is

@

Pl

ot

Rating
standard

the FM

Press

the 98MHz

tuned

seach

AUTO

J

Press the Memory

button.

.f

The Memory
lights about

J

PRESET

the

Press

the Memory

during
indicator

The

Pl

Press

tuned

AUTO

Press

The

lights and the
LED

PrCSS

The

goes

SET

lights.

.l.

PRESET LED

lights.

the AM

1080kHz

the

seach.

+

the Memory

.1.

Memory

flash6s.

of Pl

T

thE PRESET

.1.

Memory

and

out

of

LED

@ tnepRg-

SETof

not

Remarks

button

with

indicator

3 seconds

Pl

of

button and

button

indicator

PBESET

P2

indicator

the PRE-

lights.

P2

Pl dbe:

lights

and

with

.TEST

POINT

!h

(-)

ffira

Q_-r,",0.-..,

n

tl

E

t/r

l-#',",,,1118

iffii''i

-&-&-

qssB/ffi

C$3 l-rcr.4 1

ltsJJD-m

vEi6zr^'*

vco

g*3

*[H

,"'os

I

lel

,[3.

_

w

R2o4

==fu

','6tr#

"

"Q"

I

r;l

--srDsr

ffifll

,ffi]]

8Hffl;''"

mi

6