Kenwood KX 9050 S Service Manual

Page 1

KX-9050/S KE'WOOD

SERVICE MANUAL

From g!ass Case Panel Front mass
(BIO-189304) (Am-290301» «ABC-015770229050) «mamas-o4)
(AGO-022 2021905051

Knob Cassette Ind Assv Knob Knob

Knob
"(2943277030 (A53713$8A03:90509 «294328-03? Phone ,ack (K29-4330-04) (9433204,
(Asa-13500190505) (E1170190-05)
Pin iack AC cord bushmg AC vower covd Minilure phone jack
(E1340636v05) (J42-0078-05) 530' ) (310188-05)

SHde switch
SIN-2094051

* Refer to parts L; . on page 59.

Page 2

KX-9050/S

CONTENTS

ACCESSORIES ..................................................... 2
INDICATORS ........................ 3
DISASSEMBLY FOR REPAIR 4
CIRCUIT DESCRIPTION .......................................... 5
MECHANISM DESCRIPTION .... 24
ADJUSTMENT ........................... 30
REGLAGE .......................................................... 33
ABGLEICH ............................................................ 36

ACCESSORIES

WIRING DIAGRAM ................................................ 40
PC BOARD ................... H 41
SCHEMATIC DIAGRAM . . 45
EXPLODED VIEW (MECHANISM) ...................... 57
EXPLODED VIEW IUNITI 58
PARTS LIST .. 59
SPECIFICATIONS ..

AudIocord.. , .
(BO-050505)

INSTRUCTION MANUAL

38070688-00 ENGLISH
EGO-068900 FRENCH
88070691-00 GE, DU. IT

Svsem control cord ....... I
IExcepI for Ihe UK and
Europe) (BO-0977705)

Page 16

KX-9050/ S

16

CIRCUIT DESCRIPTION

Operating specifications

Function description

(1 ) Features

(I)

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L'

:7 B

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Amorphous 3 head closed loop dual capstan
Direct drive capstan/reel/actuator motor
A.T.C.S (AUTO TAPE CALIBRATION SYSTEM)
Fine adjustment

Power loading

D.P.$.S

CD direct

Equipped with Dolby B.C.S (S available only in
KX»9050$)

Full cassette stabilizer

Dual FL display

High bias system

Center mechanism layout

) Objects of control
Cassette mechanism 20407099245 (KX-9050)

:D40»1224-15 (KX790505)

® Loading mechanism :D-4070996-05

@ IC ZTC9162N, TC9164N
(<1) Display :FL, LED

(5;) Recording/playback circuit unit

1.

2 Specifications, depending on model
Diode switch provided/not provided (KSO-KRl)...
Dolby S provided/not provided.

Operating Specifications

®

ATCS (AUTO TAPE CALIBRATION SYSTEM)

Carries out automatic adjustment of the bias value (10
KHz, 16 adjustable steps) and level value (400 Hz, 16
adlustable steps),

Bias Adjustment

400 Hz and 10 KHz are generated alternately after for-
warding the reader tape in blank (approximately 10 se-
conds), and their levels are monitored. The bias value
is changed while doing so, and the value at which 400
Hz g 10 KHz is regarded as the optimum bias value.

Level Adjustment

After finishing the bias adjustment, the level obtained
when entering the 400 Hz signal without passing
through the head is stored in advance in the memory
(relerence). Next, 400 Hz signal is generated bY the
oscillator, and the Rch level is monitored. The level value
is changed while doing so, and the value in which refe-
rence § Rch is regarded as the optimum level value.

Bias Fine Adjustment (BIAS CONTROL)

Fine adjustment is available only after ATCS presetting
(when ATCS lamp is ON) (irrespective of mechanism
operation). The variable range is up to :3 steps. No
variation is available, however, when the said steps
exceed the 16-step variable range (the bar of the right-
most side flickers). There is no variation when the key
is kept merely pressed.

Preset

The bias value and the level value preset bY ATCS can
be stored in the memory. The bias value and the level
value are stored in the memory when the PRESET key
is pressed after presetting the ATCS. There are 3 types
of memory, chrome, normal and metal. The memory is
recalled when the PRESET key is pressed while the
ATCS lamp is lit, and the function is reset when the key
is presed again.

ATCS is preset by carrying out the steps a. and b.
above. When either a. or b. can not be preset due to
malfunction of the tape and other reasons, reset the
ATCS mode, and return the bias value and the level
value to the initial state.

Power loading (OPEN/CLOSE)
In the basic operation the power loading motor is rotav
ted for a given time (forward rotation) when the
OPEN/CLOSE key is pressed once. When it is pressed
again, the motor is rotated for a given time (backward
rotation), and the door is closed. When the door is fully
closed, the switch recognizing its closure (CLOSE SW)
is turned ON. There are the following kinds of special
operation.

a: If a basic operation key (PLAY, FF, REW, REC,
PAUSE, STOP) is pressed while the door is opening,
the door is closed, and then the operation corres-
ponding to the key is question is started. (The door
is merely closed when there is no cassette in the
drive. it opens again, however, when RECo r REC
PAUSE is pressed).

b: OPEN/CLOSE operation is possible also when
POWER is OFF. (When AC is ON). If POWER is tur-
ned ON or OFF when the door is open, it is cl osed,

c: If the OPEN/CLOSE key is pressed with the m echa-
nism in operation, the operation of the mechanism
is stopped, and then the door is opened.

d: If the door is touched gently with the hand while
it is opening, the motor is rotated for a given time