Yamaha K-1020 Service manual

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This manual has becn It has

been assumed that basic servicc

Products, are alrcady known WARNING: Failure to

IMPORTANT:

Thc data rcscarch, engineering, and products. notice Servicc

provided

Modifications

or obliSation to retrofit. Should any discrepancy appcar to exist,

Division.

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IJITPORTANT NOTICE

providcd

for

use

the

of authorized

proccdures

understood

and

follow

appropriate service and safety may result in product that all servicc required should be dppointed

The authorization, ccrtification, establish a

is belicved to

Static dischargcs can destroy experrsive components. Discharge body may have gauge

Turn the you

personal

perform

to

rer vice

prescntation

principle

scrvice

are, therefore,

wires

black

unit

OFF during disassembly and

power

apply

as specificd.

reprerentativc.

or

salc

agent relationship of any form.

be accurate and applicable to the

departments

inevitable

accumulated by

connect to this buss).

to th€ unit.

inhcrant to the industry, and more

users,

by the

iniury, dcstruction of expcnsivc components

For

of this manual to any individual

recognition

of and changes in specification are

grounding

0n

f--ffir-il

-(D'S,0

Yamaha

Retailers and their service

have

and

thesc reasons, we advisc all

performed

Yamaha

by an authorizcd Yamaha Retailer or

of any applicable

are continually striving

yourself

parts

not

thereforc procedures

whcn

or

unit/s

indicatcd on the covcr.

please

ground

to the

replacement. Recheck

(D

personnel.

specifically

been rcstatcd.

servicing this

Yamaha

firm

does not constitute

technical capabilitites, or

to

subject to change without

contact the distributor's

any static electricity

buss in the unit

Yamaha

product

failure

and

improve Yamaha

product

work

all

of the

owners

The

your

(heavy

before

the

I

H

CONTENTS

I

TOSERVICEPERSONEL

REARPANELS... .....1

BLOCKDIAGRAM ......2

SPEC|F|CAT|ONS.

INTERNALVIEW. ......3

DISASSEMBLYPROCEDURES . .....

MECHANICALADJUSTMENTS. 7

ELECTRICALADJUSTMENTS . ....9-11

........1

......3

4-6

-9

LSI DATA

TIMINGCHART .......13

PRINTED

wtRtNG .. .. .. . 18

fcBLocK SCHEMATICDIAGRAM PARTSLTST.

TABLES

CIRCUIT

BOARD

(Pattern

Side) . .

..19-21

.....22,23

12

14 - 17

.24-36

SINCEI'87

@YAMAHA

NIPPON GAKKI CO., LTD. HAMAMATSU,

2.5k 533

Printed in Japan.

El

@

JAPAN

'85 . I

K-ro2()

..--.-

T

e-^

*

t{

TO

I

Cntical

Components and to

those

2.

Leakage When verify insulated

Meter by

0.1 Leakage Be

sure to

REAR

I

U.S.A.

SERVICE PER,SONNET

Components

must be

originally Current

service has

that

from

impedance

F

5r

current

test

I having replaced

installed.

Measurement

been

all

exposed

supply

should

must

for

leakagewith

nformation. special

characteristics

parts

with

(For

completed,

conductive

circuits.

be equivalent

not

exceed

the AC

having

l20V Model

it

is

imperarive

surfaces

to 1

0.5mA. plug

specif ications

PANELS

& Canadian

models

are marked

Onlv)

ihat

are

5O0 ohm

polaIrres.

in tjoth

'

equal

yo,

properly

shunreo

WALL OUTLET

INSULATING

.@.

TABLE

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British

European

model

& Australian

model

models

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SPECIFICATIONS

T

K-|o20

Type

Head R

Motors

Wow

& Flutter No more

Fast

Wind Time

Frequency

Normal Chrome Metal

Signal to Noise

Dolby Dolby B Dolby dbx on

Harmonic

Normal Chrome lvletal

Response

tape

(-20d8)

tape

oft

on on

C

Distortion

tape

& Erase

(-2OdB)

Ratio

P

Heads: Combination, Pure Sendust with

Heads: lon-plating Ferrite, Double-gap

4-track. 2-channel stereo

triple-laminated

Capstan:

Reel:

No more

About

(High

DC Servo

Flat torque

Assist:

+0.06%

than

than 0.03%

70 seconds/45

winding)

Speed

to

20

18.O00H2

to

20

20,000H2 + 3

to

20

23,000H2 t 3

More than More More More

Less than 0.5% Less than Less

Motor DC Motor DC Motor

(W.

Peak);

(W.

RMS)

seconds

(C-6O)

t

59

than

67

than

75 dB

than

95

0.5%

than

0.8%

core

dB

3

dB dB

dB

I nput

Sonsitivity

ne 40

Li

Output Level/Load

Line Head

ohones Channel Cross Talk

Power Supplios

U.S. & Canadian Models European Model British & Australian General

Consumption

Power Dimensions{WxHxD}

Weight 7.6 kg Specifications are subject to change without notice.

(u)......

(c)

......

(A)..........

(G)..........

(B)

..... . British

(R1..........

I mpedance

Separation

i'125

Model

U.S.A. model Canadian Australian

European model

General

(31

Hzl

Models

model

5O

Hz)

1 1

360

3.6 mW/8

12OV

22OV AC,

220

1240V

435 x 134

17I

la"

24OV

120

0

I

mV/30 k-ohms

mV/47 k-ohms

x

{16

ohms

40 dB

dB

60

AC,6OHZ

50HZ

AC,5OHZ

AC. 50/60H2

watts

28

mm

x 380

x 15"

5-1

14"

lbs.

12 oz.}

I NTTNNAL

I

VIEW

PoWER

O

€) @

()dbx @

@cnpsreru (D

@

Op-COM

@powEa

TRANSFoRMER

U.S.A.

& Canadian models: European model : Australian & General model:

powEn vnrru

Ootby Circuir Board

clRcurr BoARD

crRcurr

Circuit Board

MoroR neel MoroR nssrsr MoroR

lC: LM6402G-494

crRculr

GA68600

British

G468620

BoARD

models:

(1)

GA68590

GA68610

3

K-ro2()

DISASSEMBLY

I

1.

Adjustment

head a. Remove b.

Remove 2 screws

of mechanism unit and replacement of

parts.

the

cassette

Plate.

c.

Remove pl

*

In this

can be

4 screws @ in Fig. 1 and remove the

ate.

state, the

replaced.

PR,OCEDURES

lid.

in f

O

head

'l

ig.

be adjusted and its

can

remove the

and

blind

front

parts

Fis. 1

Bemoval

2.

Remove 5

d-

of

mechanism unit

screws

cover.

b.

Remove

Cassette Lid

c.

Disconnect connectors

the

cassette

Fis.4.

in f ig. 3 and remove the top

@

lid.

#1

through

rfi,

+7

and

Fis

#8

d.R

m

3

in

d.

Remove 2 screws O in Fig.

playback

e. Remove the

head.

screw

@

head.

f.

Remove the E ring @ in

pinch

from

roller.

the

ring

E

roller.

washer

@

O

side

g.

Remove

up

side

h.

Bemove the

.

wiring diagram

Hsd {viewed

nderside)

u

replace

2 and

in

f ig. 2 and replace the erase

f ig. 2 and

in

f ig. 2 and replace the

in f

ig. 2 and

replace

the record/

the supply

the

take-

idler.

.

CONNECTOR

oA,

G, B

models

WIRING

.R

model

Voltage

.U,

C

models

rr)

RE

t, BE

BL

R.

A,

lF6frE;'Tfil

-

G, A mod.l! otrl

\

312

Fig.2

E: G

RE: A, B

1

model-

models

I

: I

i

I

; i

i

!

d.

Remove 4 screws

mechanism

unit

gradually

€)

in

f ig.

5 and

to the rear.

pull

out

the

Replacement of capstan

3. Remove the mechanism unit.

a.

Remove 4 screws

b.

plate.

.

Srtting flywhsl belt (viryed

trom the rsr)

@

motor

in f lg. 6 and

remove

the

A

back-

r''

Fig.5

O

WIRING

OF MECHANISM

Reel Motor

UNIT

-

Sensor Circuit Board

Lavel

Fig.6

A

I

/

I

J

i

j

{

i

K-ro20

\A

^

molor.

c. Remove 3

screws

Capstan

[)

Motor

in Fig. 7

replace the capstan

and

Remove 2 screws @ and

remove the

Remove 2 screws

s.

reel motor installation

@

motor.

nuts @ in Fig. 9 and

plate.

ln

fig.9

and

replace

the

reel

Fig.7

4.

Replacement

Remove the mechanism

a.

b.

Remove

2 screws @ in

of reel

motor

unit.

Fig. 8 and remove

Plate.

c. Remove the reel base as shown

"

Note

coil springs

that

of

the supply

reel are different. Supply side: Silver Take-up side:

d.

Remove

e.

Remove

flywheel

Green

(Refer

the back

plate

the washer @ in f ig. 8 and

(take-up

side).

to

in

Fig.

8.

reel

and

6.) remove the

the blind

takeup

Replacement

5.

of assist motor

a. Remove the top cover.

b.

Remove

the

blind

plate.

c. Remove 2 screws @ in

motor installation

d.

Remove 2 screws @ in

plate.

motor.

Motor

Assist lnstallation

Plate

Reel Motor lnstallation

f ig. 10

f ig.

remove the assist

and

replacethe

10 and

Plate

Fig.9

assist

F

Push the reel base

the ring.

to

the

rear

and

remove

Fig.

Assist

Motor

l0

Fis.

I

6

K-ro20

MECHANICAL

I

1. Before o

1 Check

2

4

5

6

7

t0

adjustment

magnetization,

head

Since are likely istics,

to introduce

it is very

demagnetized

Adlustm€nt

at€m

clear-

between

ance

side

take-up pinch

roller

capstan

and shaft.

Panch Roller Timing

re-

of

Height cord/playback h€ad

and tape

guide

rdlpl a

R eco back

angle

SupplV

pinch

h eight

Azimuth

Check tion

head and tape movement.

Check

9

and BEW uP

Tape

Wow/ F

head tilt

side

roller

Posr

of erase

each

FF

t

im€s

speed

V'

tak€

lutter

and

ADJUSTMENTS

dust

in

error

important that

cleaned.

Test

Tape

Point

ig.o

Headgauge

(M

Headgauge (M-3OO)

-n."as"ffi

Fig.F

(M-300)

A.C.V.M.

LINE

1OkHz,

-10d8 (MTT-

1 14)

AC-512 712,22a c-60

3kHz,

-10dB

(MTT-

111)

OUT

LINE OUT

Oscilloscope

t\,

-T"rq*t*

accumulations,

the

various

heads are

the

Instrument

required

3oo)

ir-

""t*tt"

(MC-109C)

(Cassette

Wow,/f

meter Frequen cy counter

type)

lutter

etc.

character-

properly

Mode

PAUSE

STOP

I I

j I

I lrollers I I itake-up ]

L

I I

%H".l:iH:, lAdiustmenti

head

lWith jpushed

up,

timing

icheck

pinch

which

on

side and

isuoolv

lcontact

side capstan

1l

I

lwithM300

I lblock I lverticallY I lcord/Playback I lhead,

I lthat M I lgurg" i ]oecomes

I l(Fis.

i i

PB

placed

on

adjust

3OO

and block

Parallel

E)

rv"""u,-"

REWtorque, take and back tensi- I on

I I l

I I

I I I

Check whileplaying

jback

tape.

Fr

up torque

torque. Back

speed

3kHz

lnstruments

2. .

o . . a o o .

base

Gauge

Head

frequency oscillator

Audio Oscilloscope Mirror

Cassette Torque meter Wow/flutter meter

D.C.V.M.

A.C.V.M.

Fig.

Fig

at

re'

so

I I I

I lthan r lTape

1 lthe

I

(DC (AC

A More

B

side

Supply oinch rotler height adiusting screw c)

rtn

n.i. justing

(Fig.

C)

aa-

screw

-T-

i 1 i

tension:

lAdjustleaf

(5

spring

t)

i{Fie.

I I

f

ls€mr

'xed

ar,leresrstorat

test

back

the

lg_apstglt

(Fiq.

J)

Motor.

required (M-300)

{MC-109C}

Voltagemeter) Voltagemeter)

than O.5

Take-up

]

should

roller

]

rotating first.

I I

l

gauge

Head

]

pass

through smoothlV

I lwathout

(Fig.

Jtacting lguide.

Eavback

R is maximum

]and jand

Phase

lshould

(Phase

60")

should

center of erase

smoothlY'

lhead lCapstan lshould

--ffi?,"'c,'

]35-559/cm

REW

FF, more Back

I ]5-1Og/cm

steps)

] I

Normal; Less High speed: Less

varr

3ooo

I3OOO J

of the

I

than O.O5%

Less

I

(WRMS)

natine

side

Pinc start

should

block con-

i.ts

pinch

(Fig.

F)

output

difference minimum

be difference

move in

(suppty

move

smoothlv.

torque

7oglcm

than

tenslorl:

seconds

ssseconds

+.:Hz

+.,

!uz

-rc

roller

than

of

less

side)

than

L

u5

Remarks

I

ot both

timing

lli

samultane-

is

lsides

or supply

]ous

precedes,

lment

I

adj.ust'

requrreo.

rs

t--

adj

Repeat

3 to 6 and

in steps

screw

apply

parnt

upon comp-

of

letion

r9!!.

Adjust spacer as Fig. H.

f" torque, center of tron.

]

adjust-

by

shown

"Ot.n

read the

deflec-

wow/flutter

Check while confirming

frequency

3kHz with wow/flutter meter counter.

side

ustment

lock

using

t.t"

{

/^r

2-r'1

.^

in

"P

t

l^.

I

I I

l'o?lJ"li3l

clearaoce

'";,TlI

l6190r.

K-ro2()

-1

-\

r^

*Make

sure

;;;;;*

to

reconfirm after

Supply

Side

Height

Adjust

Take-up

Pinch

Scrw

Be

'

Be

'

scrry

sdjustment

side

Capstan

Tape

Roller

sura to

tighten

sureio

apply scrw

after sdjustment.

Pinch

Floller

Fig. A

Er€g Head

Hesd

the head fixing

lck

\

F ix

..'

Screw

Tilt

painr

Angle

scrfl

to each

Adjust

securely,

adjusiing

Adjust by beoding head contscting pinch

roller.

clearance

'Confirm

Take-up

Scrw

acljustment. ance head up

between

base

srdes.

There

on both

Side

Pinch

part

of supply side

and

should

pinch

lhe

supply

Roller

t;ming

be a

arm

and

base

atter

clear-

and

t6ke-

Fig.

B

c

a

--

---A:'

@

il I It |

il t ililt l

L-

ll

-_:-J

[r

l_-----

.il||ti----

.il|t

.t

|

"r-_I_----'

,/a\

(t@])

\7

Head

Gauge

M.300

e

Fig.

D

Adjust clearance the

upper

so

that

is obtained

and

lwor

the same

parts.

at

t-rg.

E

y"'

I

Head

Gauge

M-300

Fig. F

Difference beMeen Less

than

A .nd

l/2

B

Fis.

G

E

K-ro2()

'

ELECTRI

I

Use spacer

CAL

t

u

to

h8sd

adjust the

heighl

Capslsn Moto.

(]-\

\

\\

ADJUSTMENTS

He8d Hei0hr

\\

Orivcr

/

\

Fig.

Fig. J

Teosion

(5

mode

iteps)

8ek at Playback

{

@ @

H

@

Fig. I

.

\')A

O

PLAYBACK

*

Make sure to use taDe.

Alignment Normal CrO2 METAL

o

Proceed

F;f

E.o^-"

i iDc.offset

i-t-lFr"yb".ki'^

I I i I

F_+

s i etayuacr

I

i

J

I ],.I,.r';',,tuo|,, I

a

ldbx I I

.

RECORDING ADJUSTMENT

.

Proceed with the

t-Aai-'tf"ntT ["n".n=."";r

Meter

r

1(+4.5dBl

r

ltno

fF;k

Meter signal

l(OdB)

i '

9

ADJUSTMENTS

a new tape of

tape TDK AC223 or YAMAHA NR TDK AC512 or TDK ACl12 or

with the

playback

adjustments after having

*r;,-.";;-l-;""-

r

-

r

| I

r".oonre

response

rc

uott

L"*f

rrequency

conf irmation

conTtrmatton

recording

,

I

j

I

(J

{3t80

I 1

adiustments

-"t^Tt

"

lL^;F;;*

OUT

rLiNE

li-,i"

1 that LINE OUT voltage

1 that

, I L

I

EC standards

YAMAHA

i{tztzc

1stsa, \ i

\toonwo/m/

Mrr.3s6u I r-rr.re

+

70ps1

tUU + /Ups,

T..rj:l:jt-

l-Au;it

]fll$,"."",

oscillator

for

a test

60

CR

60

MR

60

-j-,*l1;l*-[

J;';iat-r-

lrP2{B)-E

l

I I

_+

i 1 1 lshoutd

Tpl

1

(dbx

]

after

,.

faoa*".

finished

Lrrveou-f-eivnr---trl

_ __

circuit

having finished

.

I

oui

-rp2 board)

'

M"".u,"-"nt

Appry a rkHz

from

signal that

LINE OUT

$'J*,i,'-iyJrlirtase

f,ppty " r ri.

from

LINE OUT

is

360mV

'is

*

Use 360mV

unit.

this

the mechanical

Tffr#

D.cr/M

I

i

(Acvort/da

rvteter)

; 6nt

1 i lshould

I

D.C.V.M.

1-____1

playback

the

sine *;-]u"*.tLr-r

lN

LINE

LINE lN

(-gdBV).

{-gdBV}.

so

voltase rs

*u*

rinu

so

voltage

_l _

(-9dBV)

adjustments.

JW";;11

frtor l

I I

I I I l

f__t

i i

1

Srop 1 vRTOt

]

I

adjustments.

Jnai"tln"',tl

iVR5O4

is

I

I ltisf't.

fvnsor

1VR502 I llight.

i L

] I

*roir'il-

vR102(R)

uRlon-L)

vR1o4(R)

t-f---T;"*;,"*;'"

]

{dbx

I I

l*aaE

{R)

I

tr-r

(R)

for

0dB as

_

circuit

board)

*;-

r"n-*,-i

(red}

should

I

lrisht

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150

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