Aiwa AD-1800 Manuel utilisateur

Type:

Recording

track

system:

4-track,

2-channel

Circuit:

Power

source:

Power

consumption:

Frequency

response:

SN

ratio:

Wow

&

flutter:

Tape

speed:

Recording

system:

Erasing

system:

Rewind

time:

FF

time:

Usable

cassette

tape:

Motor:

Head:

Input:

MIc:

SPECIFICATIONS

Hi-Fi

stereo

cassette

tape

deck

LINE

(iN):

with

Dolby

system

and

DNL

DIN

(IN):

1

IC,

62

transistors,

43

diodes,

2

FET,

3

LED

Output:

“EE”

model

LINE

(OUT):

AC

110

~

120V/220

~240V

switch

changeable,

50/60

Hz

“UK”

model

AC

120V/240V

switchable

50

Hz

DIN

(OUT):

24W

LH

tape,

30

~

14,000

Hz

Fe-Cr

tape,

30

~

18,000

Hz

Headphone:

CrO,

tape,

30

~

17,000

Hz

Dimensions

(w.h.d):

65

dB

(Doiby

NR/DNL

ON,

Fe-Cr

Weight:

Accessories:

tape)

0.05%

(WRMS}

4.76

cm/sec.

(1-7/8

ips)

1.0%

AC

bias

AC

erase

95

sec.

(w/

C-60)

95

sec.

{w/

C-60)

C-30, C-60,

C-90,

(C-120)

AC

hysterrisis

synchronous

motor

Ferrite

guard

head

(FGH)

Max.

input

sensitivity:

0.25

mV

Impedance:

200

ohms

~

10k

ohms

Set

using

ISO

screws

DATE

OF

ISSUE

25/12/1975

Max.

input

sensitivity:

50

mV

Impedance:

100

k

ohms

or

higher

Max.

input

sensitivity:

0.1mV/k

ohm

Impedance:

2.7

k

ohms

Standard

output

level:

0.775V

(O

VU)

Optimum

load

impedance:

50

k

ohms

or

higher

Standard

output

level:

0.775V

(O

VU)

Optimum

load

impedance:

50

k

ohms

or

higher

Load

impedance:

8

ohms

423

x

152

x

295

mm

(with

dust

cover)

7.5

kg

(with

dust

cover)

Dust

cover

x1

Tape

cassette

x1

DIN

cord

x1

Head

cleaning

pole

x1

©

The

external

design

and

the

specifications

are

subject

to

change

without

prior

notice.

e@

Dolby

Noise

Reduction

Circuit

Under

License

from

Dolby

Laboratories

Incorporated.

e@

The

word

‘Dolby’

and

“‘Double-D”

symbol

are

trademarks

of

Dolby

Laboratories

Incorporated.

MODEL

AD-1800EE,UK

AIWA

DISASSEMBLY

INSTRUCTIONS

1.

To

Remove

Wooden

Cover

5.

To

Remove

Dolby-NR

Circuit

Board.

(1)

Remove

six

screws,

(1)

through

(6).

(1)

Pull

off

the

Dolby-NR

circuit

board.

(Refer

to

Fig.

1}

(Refer

to

Fig.

4)

6.

To

Remove

DNL

Circuit

Board

(1)

Pull

off

the

DNL

circuit

board.

{Refer

to

Fig.

4)

Dolby

NR

Circuit

Board

Dolby

NR

Circuit

Board

Sy

2.

To

Remove

Chassis

i"

<

Fig.

4

>

(1)

Pull

off

the

six

control

knobs.

(7)

REC/PB

Circuit

Board

(2)

Remove

six

screws,

(1)

through

(6).

(Refer

to

Fig.

2)

7.

To

Remove

Auto-Stop

Detectron

Circuit

Board.

{1)

Remove

two

screws,

(1)

and

(2).

(Refer

to

Fig.

5)

8.

To

Remove

Auto-Stop/CrO,

Switch

Circuit

Board

(1)

Remove

one

screw

(1).

(Refer

to

Fig.

6)

3.

To

Remove

Jack-1

Circuit

Board

(1)

Remove

three

nuts

((1)

through

(3))

and

unsolder

lead

9.

To

Remove

FF/REW

Muting

Circuit

Board

of

capacitor

(4).

(Refer

to

Fig.

3)

(1)

Remove

two

screws,

(2)

and

(3).

(Refer

to

Fig.

6)

4.

To

Remove

Rec./Pb

Circuit

Board

(1)

Remove

three

screws,

(5)

through

(7).

@

FF/REW

(Refer

to

Fig.

3)

Muting

circuit

board

Auto

stop/

Cr02

switch

circuit

board

AIWA

MODEL

AD-1800EE,UK

10.

To

Remove

Switch/Volume

Circuit

Board

(1)

Remove

sixteen

screw,

(1)

through

(16).

(Refer

to

Fig.

7)

11.

To

Remove

LAMP

Circuit

Board

(1)

Remove

one

screw,

(1).

(Refer

to

Fig.

8)

12.

To

Remove

Meter

Circuit

Board

(1)

Remove

two

screws,

(2)

and

(3).

(Refer

to

Fig.

8)

13.

To

Remove

Bias

Osc

Circuit

Board

(1)

Remove

two

screws,

(4)

and

(5).

(Refer

to

Fig.

8)

14.

To

Remove

Stop

Muting

Circuit

Board

(1)

Remove

one

screw

(1).

(Refer

to

Fig.

9)

15.

To

Remove

LED

Circuit

Board

(1)

Remove

two

screws,

(1)

and

(2).

(Refer

to

Fig.

10)

16.

To

Remove

Counter

Lamp

Circuit

Board

(1)

Remove

four

screws,

(1)

through

(4).

(Refer

to

Fig.

11)

<

Fig.

11

>

17.

To

Remove

Motor

Circuit

Board

(1)

Remove

two

screws,

(1)

and

(2).

(Refer

to

Fig.

12)

18.

To

Remove

Jack-2

Circuit

Board

(1)

Remove

the

nut

and

washer

(1).

(2)

Remove

six

screws,

(2)

through

(7).

(Refer

to

Fig.

13)

MODEL

AD-1800EE,UK

AIWA

Low

level

peak

lamp

lights

High

level

peak

famp

lights

NEW

CIRCUIT

DESCRIPTION

+7

2.

Point

Peak

Indicators

Since

VU

meter

cannot

follow,

indicated

level

is

lower

than

actual.

—_

e@

Peak

indicator

circuit

diagram

B

+3

>

®

od

ao

a

i:

=

BH

VU

meter

~

indication

Inadequate

damping

produces

higher

—_—

LEVEL

indicated

value

than

actual.

Input

waveform

TRi

METER

"

:

Time

—>

.

af

a

.

<

Fig.

15>

e@

Recording

Level

Settings

According

to

Tape

4—+

Distortion

can

be

suppressed

to

below

3%

and

optimum

LED(L)

LEDIM)

recording

performed

by

setting

the

recording

levels

as

®

ry

-

14

Bi

follows.

HIGH

;

F

cae

Ri

LOW

LH

Tape:

Lights

occasionally

at

+3dB;

does

not

light

at

TRS

Re

|

+7dB

TR

,

Fe-Cr

Tape:

Lights

often

at

+3dB;

lights

occasionally

at

©

=

+70B

a

\

wy

ss

i

6

CrO2

Tape:

Does

not

light

at

either

+3dB

or

+7dB

i

T

I

Pr

|seRe

Zo

i

Ra

|

Input

and

output

level

distortion

characteristics

<

Fig.

14

>

Presently

employed

VU

meters

are

capable

of

indicating

continuous

wave

signals

of

approximately

300msec.

They

are

incapable

of

following

faster

pulse

type

signals

however,

resulting

in

an

indicated

value

considerably

lower

than

the

actual!

jevel.

Thus

if

the

recording

level

is

set

in

reference

to

the

VU

meters,

an

instantaneous

high

level

input

can

cause

an

over

level,

resulting

in

distortion.

Peak

indicators

are

provided

for

preventing

this

situation

and

are

capable

of

indicating

to

about

Imsec

instantaneous

inputs.

Earlier

single

point

designs

(a

single

peak

indicator

which

lights

at

+6VU)

however,

were

ambiguous

and

difficult

to

interpret.

The

indicator

was

not

supposed

to

light,

but

if

it

did

not

light,

the

level

could

not

be

determined.

The

2

point

peak

indicator

system

employed

in

the

AD-1800

represents

an

improvement

over

earlier

systems.

Two

peak

indicators

are

used

with

different

lighting

levels

(42.5~3VU

and

+6~7VU),

allowing

more

accurate

peak

indication.

@

Circuit

Description

ia)

Output

level

(dBm)

Distortion

(%)

20

3 5

7

.

gy

|

Input

signal

(1)

is

amplified

approximately

10dB

by

TRt.

Dput

level

(dB)

<

Fig.

16>

Previously,

it

passed

from

(2)

through

the

SFR

and

was

rectified

and

connected

to

the

meter.

However,

since

the

meter

load

is

heavy,

TR1

output

voltage

became

varied

by

SFR

adjustment,

preventing

connection

to

the

peak

indi-

cator

circuit.

TR2

is

therefore

inserted

at

that

point

as

an

emitter

follower,

reducing

meter

amplifier

output

impedance

in

order

not

to

influence

meter

and

peak

indicators.

The

signal

to

the

meter

amplifier

is

divided

at

(3).

The

peak

indicator

signal

is

rectified

at

(4)

and

the

voltage

is

applied

to

SFR2.

At

this

point

the

signal

from

the

other

channel

is

mixed,

while

the

peak

indicator

lighting

level

is

determined

by

adjusting

SFR2.

When

(6)

reaches

a

specified

voltage,

TR3

and

TR4

Darlingtons

become

on,

and

LED

(L)

lights.

C1

is

inserted

at

this

point

to

provide

a

certain

degree

of

lighting

time,

since

instantaneous

lighting

with

a

pulse

signal

input

would

be

difficult

to

observe.

The

voltage

at

(6)

is

divided

at

R3

&

R4.

By

a

higher

level

than

TR3

on

level,

TR5

and

TR6

become

on.

R1

and

R2

are

inserted

as

protector

resistors

to

control

the

current

flow

through

the

LED.

AIWA

MODEL

AD-1800EE,UK

=

Hall

IC

Tape

End

Detector

Circuit

In

order

to

remedy

the

drawbacks

(noise,

life,

maintenance,

etc.)

of

earlier

mechanical

contact

type

tape

end

detectors

(G.

switch

and

reed

switch),

a

magnet

and

Hall

IC

are

employed

in

the

AD-1800.

stopping

circuit

(|

®

;

G.SW

|

~—

d+

©

|

t

|

GSW

|

!

©

I

ic

1

AD-1500

oe

4600

@|

Hall

IC

1

Ring

magnet

Oh

AD-1800

<

Fig.

17

>

e

Automatic

Stopping

Circuit

Diagram

When

a

magnetic

field

is

applied

at

right

angles

to

the

current

flow

in

a

Hall

element,

an

emf

(Hall

voitage)

becomes

generated

at

right

angles

to

the

magnetic

field

and

current

flow.

As

the

output

of

the

Hall

element

is

smail

(0.3V

at

|

=

20mA,

B

=

1000

Gauss),

the

AD-1800

element

is

incorporated

into

an

1C

amplifier

(more

than

2.5V

at

Icc

=

13.5mA,

B

=

350

Gauss).

<

Fig.

18

>

Hall

element

e@

Operating

Description

The

waveform

at

point

(b),

shown

in

Fig.

19,

pertains

to

stopping

circuits.

An

identical

waveform

can

also

be

obtained

from

a

ring

magnet

and

Hall

IC.

Six

magnetic

poles

are

provided

at

the

outer

circumference

of

the

ring

magnet,

producing

more

than

500

Gauss

at

2mm

from

the

outer

circumference.

The

magnetic

flux

pattern

through

1

rotation

of

the

ring

magnet

is

shown

in

Fig.

21.

Approx.

2mm

OFF

+8

Ring

Peas

Hall

IC

|

ON

| |

)

vs

Point

(b)

waveform

<

Fig.

19>

<

Fig.

20

>

Circuit

board

x

2.

28

Oke

flux

5

PA

;

25

1

rotation

23

<Fig.21>

The

flux

variation

through

ring

magnet

rotation

(coupled

with

counter

pulley

rotation)

imparted

to

the

Hail

IC

results

in

an

output

as

shown

in

Fig.

22.

Zz

4

+

®

>

3D

es

2

Sf

6

8.

O8b=-2

fase

Transistor

on

level

<

Fig.

22

>

lf

this

voitage

were

applied

directly

to

TR1

base,

the

transistor

on

and

off

times

would

differ,

since

the

voltage

is

2V

even

with

0

magnetic

flux.

R1

and

R2

perform

dividing

in

order

to

equalize

on

and

off

times.

TR1

collector

output

voltage

waveform

(at

b)

becomes

the

waveform

applied

to

(b).

e@

Hall

iC

Handling

Cautions

The

Hall

element

is

located

within

the

IC

as

illustrated

in

Fig.

23.

If

the

magnet

position

becomes

disturbed,

or

its

distance

increased,

the

IC

output

declines.

Caution

is

therefore

needed.

2:5

12.0

1.

Vee

2.

Output

1

3.

Output

2

4.

GHD

|

2 3

4

<

Fig.

23>

Specified

position

is

approximately

2mm

from

magnet.

MODEL

AD-1800EE

,UK

AIWA

ADJUSTMENTS

=

=©Mechanical

Section

1.

Thrust

Adjustment

1)

Turn

thrust

screw

to

move

flywheel

assembly

vertical-

ly

to

obtain

0.2~0.3mm

thrust.

(Refer

to

Fig.

27}.

“

Thrust

screw

0.2~0.3—

<

Fig.27

>

2.

Pinch

Pressure

1}

With

set

in

play

mode,

apply

500g

cylindrical

tension

gage

to

pinch

lever

center.

Press

slowly

and

measure

pinch

pressure

when

pinch

roller

separates

from

capstan.

(Refer

to

Fig.

28).

Rating:

400

+50g

<

Fig.

28>

3.

Pause

Timing

1)

Press

FWD

button

for

play

mode,

then

slowly

press

pause

button.

Observe

stopping

times

of

take

up

reel

hub

and

pinch

roller

rotations.

2)

If

pinch

roller

quickly

separates

from

capstan,

while

tape

is

running,

adjust

by

bending

pause

lever

in

direction

B.

3)

If

pinch

roller

separation

is

delayed

and

tape

winds

onto

pinch

rojler

without

take

up

reel

hub

rotation,

adjust

by

bending

pause

lever

in

direction

A.

(Refer

to

Fig.

29).

Pause

lever

Lock

plate

<

Fig.

29>

—

Pinch

lever

spring

Supporting

Plate

Assembly

Adjustments

Damper

Adjustments

1)

Screw

damper

shaft

assembly

fully

into

damper

sup-

porting

plate

assembly

(Refer

to

Fig.

30).

2)

When

damper

shaft

assembly

is

turned

2

rotations

clockwise,

observe

that

shaft

becomes

positioned

toward

square

hole

of

supporting

plate

(Refer

to

Fig.

31}.

3)

If

shaft

is

in

range

A,

turn

counter-clockwise

to

adjust;

if

in

range

B

turn

clockwise

(Refer

to

Fig. 32).

Damper

supporting

plate

assembly

<

Fig.

32>

4-2

Supporting

Plate

Adjustment

Supporting

plate

5.

1)

Lock

of

tape

selector

lever

should

engage

with

chrome

lock

plate

when

cassette

elevating

plate

raises

during

eject.

Loosen

supporting

plate

screw

and

adjust

by

moving

in

A-B

direction.

Adjust

so

that

lock

spacing

from

right

side

of

chrome

plate

square

hole

becomes

0.3~0.4mm

(Refer

to

Fig.

33).

Chrome

lock

plate

<

Fig.

33

>

Motor

Pulley

Thrust

1)

Adjust

by

raising

or

lowering

motor

pulley

so

that

space

between

pulley

rim

and

motor

becomes

1mm

(Refer

to

Fig.

34).

Motor

pulley

Driver

Motor

<

Fig,

34

>

AIWA

er

eee

6.

Tape

Running

1)

Adjust

so

that

tape

does

not

contact

tape

guide

when

running

(Refer

to

Fig.

35).

2)

{f

tape

contacts

upper

portion

of

guide

(Fig.

36).

move

adjusting

nut

in

direction

A

(Refer

to

Fig.

38).

3)

If

tape

contacts

lower

portion

of

guide

(Fig.

37),

move

adjusting

nut

in

direction

B

(Refer

to

Fig.

38).

<

Fig.

35

>

<

Fig.

36>

<

Fig.

37

>

Adjusting

nut

<

Fig.

38>

7.

CrO,

Lock

Plate

1)

Confirm

that

CrO,

lock

plate

separates

from

tape

selector

lever

when

cassette

elevating

plate

is

in

1/2

range.

2)

If

it

fails

to

separate,

adjust

by

turning

CrO,

lock

plate

adjusting

screw

clockwise

or

counter-clockwise

to

obtain

separation

in

the

1/2

range.

Apply

screw

locking

compound

after

adjusting.

(Refer

to

Fig.

39)

Cassette

elevating

plate

Tape

selector

lever

——CrOz

lock

plate

<

Fig.

39

>

8.

Tape

Speed

3kHz

+1%

Use

a

standard

test

tape,

TTA-111A

(3kHz)

or

equivalent.

9.

Wow

and

Flutter

0.05%

(WRMS)

at

PB

Use

a

standard

test

tape,

TTA-11A

(3kHz)

or

equivalent.

10,

Take-up

Torque

40

~

60g-cm

11.

FF

and

Rewind

Torque

90

~

1609-cm

12.

FF

and

Rewind

Time

90

+10

sec.

(at

C-60

cassette

tape)

13.

Automatic

shut-off

Time

4

+1

sec.

MODEL

AD-1800EE,UK

CYCLE

CONVERSION

Conversion

Steps

1.

Observe

that

POWER

switch

is

OFF

and

AC

cord

unplugged

from

power

outlet.

2.

Turn

the

set

upside

down,

take

out

3

screws

from

the

motor

cover,

and

remove

the

motor

cover.

3.

Disengage

belt

from

motor

pulley

and

temporarily

position

it

on

the

motor

fan

securing

screw.

4.

Take

out

2

motor

pulley

setscrews

and

remove

motor

pulley.

5.

Turn

motor

pulley

upside

down

and

reinstall

it

with

setscrews.

6.

Engage

belt

on

lower

portion

of

motor

pulley.

7.

—

Install

motor

cover.

e

The

thicker

side

of

the

motor

pulley

upward

is

for

60

Hz

operation,

while

for

50

Hz

operation,

the

thinner

side

of

the

pulley

should

be

upward.

50Hz

—e

60Hz

MODEL

AD-1800EE,UK

ADJUSTMENTS

ELECTRICAL

SECTION

Preparations

for

Adjustment

Required

Equipment

e@

Low

frequency

oscillator

(signal

generator}

e@

Variable

resistance

attenuator

e

VTVM

@

Oscilloscope

e

Resistors:

6002,

100k2,

27k2,

5.6k2

e

Test

tapes:

TTA-117E/TTA-161/TTA-119D

(CrO2)/TTA-

119E

(FeCr)/TTA-119A

(LH)

Adjustment

Cautions

1)

Before

adjusting,

clean

heads,

capstan

and

pinch

roller

with

gauze

moistened

in

alcohol.

2)

Demagnetize

record/play

head

with

head

eraser.

3)

Thoroughly

demagnetize

adjusting

driver.

4)

Set

playback

volume

to

maximum.

5)

Except

where

otherwise

indicated,

set

DOLBY-NR

and

DNL

switches

to

OFF,

employ

MIC

jacks

for

input

and

LINE

OUT

for

output.

6)

Standard

inputs

(OdB

=

0.775V)

MIC

Jack:

65dB

LINE-IN:

20dB

7)

Connect

100k

load

resistor

to

LINE-OUT.

@

Main

Component

Locations

LIO4

=

LIO6

Se

pe

PLAYBACK

ADJUSTMENTS

1.

Azimuth

TAPE

SELECTOR:

CrO2

Play

10kHz

portion

of

test

tape

TTA-117E

(CrO2)

and

turn

azimuth

adjusting

screw

to

obtain

maximum

output

from

left

and

right

channels.

Do

not

rotate

screw

more

than

1/4

turn.

After

adjusting,

apply

locking

compound

to

screw.

2.

Playback

Frequency

Response

TAPE

SELECTOR:

CrO,

Play

test

tape

TTA-117E

(CrO2)

and

adjust

high

frequency

trimmer

resistor

SFR101

for

equal

outputs

at

1kHz

and

10kHz.

In

the

same

manner,

adjust

SFR102

for

the

right

channel.

Rating:

1kHz~10kHz

flat

3.

Level

Meters

With

set

in

record

mode,

apply

400Hz

+25dB

signal.

Adjust

LINE

IN

volume

for

580mV

output

from

TP-3,

Adjust

meter

trimmer

resistor

SFR201

so

that

level

meter

indicates

the

Dolby

mark,

In

the

same

manner,

measure

TP-4

and

adjust

SF

R202

for

the

right

channel.

4.

Playback

Level

TAPE

SELECTOR:

LH

Play

test

tape

TTA-161

and

adjust

playback

output

trimmer

resistor

SFR103

so

that

level

meter

indicates

the

Dolby

mark,

In

the

same

manner,

adjust

SFR104

for

the

right

channel.

RECORDING

ADJUSTMENTS

1.

Bias

Trap

Coil

TAPE

SELECTOR:

CrO,

With

set

in

recording

mode,

adjust

trap

coil

L107

for

minimum

voltage

at

test

point

TP-5.

In

the

same

manner,

measure

TP-6

and

adjust

L108

for

the

right

channel.

2.

Dolby

Trap

Coil

TAPE

SELECTOR:

CrO2

With

set

in

recording

mode,

adjust

Dolby

trap

coil

L101

for

minimum

bias

leakage

to

LINE

OUT.

In

the

same

manner,

adjust

102

for

the

right

channel.

3.

Bias

Current

TAPE

SELECTOR:

CrO,

With

set

in

recording

mode,

adjust

bias

current

trimmer

TC701

for

2mV

(200uA)

voltage

at

test

point

TP-1.

In

the

same

manner,

measure

TP-2

and

adjust

TC202

for

the

right

channel.

Rating:

2mV

(200uA)

AIWA

4.

Record/Piayback

Frequency

Response

a

ar

~

We

L206

¢

L

202

:

3

L205

203

L20l

1)

CrO,

TAPE

SELECTOR:

CrO,

Test

Tape:

TTA-119D

Apply

500Hz

(—25dB)

signal

via

LINE

IN

jack

and

adjust

line

volume

for

77.5mV

output

at

LINE

OUT,

Record

5OOH2z

and

SkHz

signals

on

test

tape

TTA-119D

and

play

back.

Confirm

that

the

1kHz

level

is

within

+0.5dB

in

respect

to

the

500Hz

level.

If

the

5kHz

level

is

higher,

set

the

bias

current

higher

than

amv.

lf

the

SkHz

level

is

lower,

set

the

bias

current

lower

than

amv

Perform

adjustment

in

the

same

manner

as

described

in

Step

3

Bias

Current

adjustment.

Record

and

play

back

500Hz,

5kHz,

10kHz

and

15kHz

signals.

Adjust

CrO,

hi

peaking

coil

L201

so

that

with

respect

to

the

500Hz

signal,

5kHz

and

10kHz

become

within

+0.5dB

and

15kHz

within

+1dB.

In

the

same

manner,

adjust

L202

for

the

right

channel.

2)

Fe-Cr

Test

Tape:

TTA-119E

TAPE

SELECTOR:

Fe-Cr

Record

and

play

back

with

TTA-119E

test

tape

as

described

for

CrO2

in

step

1.

If

results

are

not

within

ratings,

adjust

as

follows.

Playback

Level

(1kHz

ref.)

Connection

|

Bias

Voltage

5kHz

level

higher

(1)

Increases

5kHz

level

lower

Decreases

Short

one

of

the

circuit

patterns

among

1~3.

Record

and

play

back

500Hz,

10kHz

and

15kHz

signals.

Adjust

FeCr

hi

peaking

coil

L203

so

that

with

reference

to

the

500Hz

level,

10kHz

becomes

within

+0.5dB

and

15kHz

within

+1dB.

In

the

same

manner,

adjust

L204

for

the

right

channel.

3)

LH-NORMAL

Test

Tape:

TTA-119A

TAPE

SELECTOR:

LH-NORMAL

Record

and

play

back

with

TTA-119A

test

tape

as

described

for

CrO,

in

step

1.

If

results

are

not

within

ratings,

adjust

as

follows.

Playback

Level

(1kHz

ref.)

Connection

|

Bias

Voltage

Increases

5kHz

level

higher

5kHz

levei

lower

Decreases

Record

and

play

back

500Hz

and

10kHz

signals.

Adjust

LH

hi

peaking

coil

L205

so

that

with

reference

to

the

500Hz

level,

10kHz

becomes

within

—1.5

+1dB.

In

the

same

manner,

adjust

L206

for

the

right

channel.

1)

2)

3)

5.

MODEL

AD-1800EE,UK

Record/Playback

Level

CrO,

Test

Tape:

TAPE

SELECTOR:

TTA-119D

CrO2

With

set

in

recording

mode,

apply

2kHz

77.5mV

signal.

Record

and

play

back

this

signal

on

TTA-119D

test

tape.

Adjust

CrO

recording

current

trimmer

resistor

SFR205

so

that

playback

level

becomes

77.5mV

+0.25dB.

In

the

same

manner,

adjust

SFR206

for

the

right

channel,

Fe-Cr

Test

Tape:

TTA-119E

TAPE

SELECTOR:

Fe-Cr

Employ

TTA-119E

test

tape

and

perform

the

same

opera-

tion

as

for

CrOz

above.

Adjust

SFR207

for

the

left

channel,

and

SF

R208

for

the

right

channel.

LH-NORMAL

Test

Tape:

TTA-119A

TAPE

SELECTOR:

LH-NORMAL

Employ

TTA-119A

test

tape

and

perform

the

same

operation

as

for

CrOz.

Adjust

SFR

209

for

the

left

channel,

and

SFR210

for

the

right

channel.

Peak

Indicator

With

set

in

record

mode,

apply

1kHz

—27dB

signal,

Adjust

LINE

IN

volume

for

OVU

indication

on

level

meter.

Set

attenuator

to

—21dB

(level

meter

indicates

+6dB)

and

turn

the

peak

indicator

trimmer

resistor

SFR203

to

the

point

where

the

red

peak

indicator

just

extinguishes.

attenuator

to

—20dB

and

confirm

that

red

indicator

lights.

Vary

attenuator

in

the

—24dB

area

and

read

the

value

at

the

point

where

yellow

indicator

just

extinguishes.

Rating:

—25dB

+1.5dB

SFR20}

SFR202

MPX

Filter

With

set

in

record

mode,

apply

19kHz

signal

to

LINE

IN.

Adjust

LINE

IN

volume

for

0.77V

at

LINE

OUT.

With

MPX

filter

switch

of

Dolby

NR

ON,

adjust

MPX

filter

coil

L105

so

that

19kHz

signal

becomes

less

than

—30cB.

!n

the

same

manner,

adjust

L106

for

the

right

channel.

MODEL

AD-1800EE,UK

DOLBY

NR

ADJUSTMENTS

e

Main

Component

Locations

and

Connections

o™

«-_™

SFR303

SFR301

(3049)

(302)

OOLBY-NR

CIRCUIT

BOARD

PB

ee

lS

am

—*

AM

o

P

‘

REC/PB

:

Bei

1

o

REC

$

OPEN

oP

VTVM

GATE

oc2av

!

oo

0

O-

SHORT

ON

DOLBY-NR

eel

Ie

pe

OFF

1)

Remove

Dolby

NR

circuit

board

from

set

and

connect

as

shown

in

drawing.

2)

Turn

SFR301

(302)

and

SFR303

(304)

fully

in

the

directions

shown

by

arrows.

3)

Position

switches

as

follows.

REC/PB:

PB

GATE:

OPEN

DOLBY-NR:

OFF

4)

Apply

400Hz

signal

and

adjust

attenuator

so

that

output

becomes

7.6mV,

then

read

attenuator

value.

Rating:

—49dB

+1dB

5)

Set

REC/PB

switch

to

REC

and

confirm

output

level

difference

of

+0.25dB.

frequencies

of

100Hz,

1kHz

and

10kHz,

confirm

an

output

level

difference

of

+1dB.

6)

Position

switches

as

follows.

REC/PB:

PB

GATE:

SHORT

DOLBY-NR:

OFF

7)

Apply

5kHz

signal

and

adjust

attenuator

so

that

output

becomes

7.6mV,

then

read

attenuator

value.

Rating:

—49

+1dB

DOLBY-NR_

switch

to

ON

and

adjust

SFR303

(304)

for

2.4mV

output.

8)

At

the

above

(step

7)

condition,

set

GATE

switch

to

OPEN

and

adjust

SF

R301

(302)

for

3mV

output.

9)

After

adjusting,

apply

locking

compound

to

trimmer

resistors.

GIG.

GEN

10

AIWA

ELECTRICAL

MEASUREMENTS

PREPARATIONS

FOR

MEASURING

Required

Equipment

®

Low

frequency

oscillator

®

Variable

resistance

attenuator

®

Oscilloscope

®

6002

and

100k2

resistors

®

Distortion

meter

®

Wow

meter

@

1kHz

bandpass

filter

@

Test

tapes:

TTA-116/TTA-114/TTA-119D

(CrO,)/TTA-

119E

(Fe-Cr)/TTA-119A

(LH)

Connection

WOW

METER

MIC.

JACK

S!IG.GEN

ATT

<~—

LINE

OUT

100KQ

Bandpass

filter

eM

Measuring

Cautions

1)

Before

measuring,

demagnetize

rec/play

and

erase

heads

with

head

eraser

and

clean

heads

with

gauze

moistened

in

alcohol.

2)

Set

playback

volume

to

maximum.

3)

Standard

inputs

(OdB

=

0.775V)

MIC

jack

65dB

LINE-iIN

20dB

4)

Connect

100k

load

resistor

to

LINE

OUT.

Playback

Output

Play

test

tape

TTA-161

and

measure

output

level.

Rating:

1.03V

+0.5dB

Recording/Playback

Distortion

Apply

400Hz

signal

via

MIC

jack

and

adjust

attenuator

for

OVU

indication

on

set

VU

meter.

Record

this

signal

on

test

tape

and

measure

playback

distortion.

Ratings:

TAPE

Test

T

ers

SELECTOR

Distortion

TTA-119D

(CrO

tape)

TTA-119E

(Fe-Cr

tape)

|

Fe-Cr

‘|

TTA-119A

(LH

tape)

LH-NORMAL

|}

Less

than

1.5%

Less

than

2.5%

Less

than

1.0%

Aiwa AD-1800 Manuel utilisateur

Manuels Récepteur stéréo populaires d'autres marques