Hitachi DE 22 Service Manual

Page 1

TK No. 1682E

@ HITACHI M22

SERVICE MANUAL (U,C,FS,BS,AU,W)

CONTENTS
Specifications ........................ 2
Disassembly .......................... 2
Adjustment .......................... 3
Inspection of mechanism ................. 4
Lubrications ......................... 4
Replacement parts list ................... 5
Schematic diagram ..................... 6
Cichit board diagram ................... 9
Wiring diagram ....................... 11
Exploded view (Cabinet) ................ 13
Exploded view (Mechanism-M L<10E) ........ 15
Replacement parts list .................. 17
KEY TO ILLUSTRATIONS

6) POWER (MAINS) SWITCH ® RECORDING BALANCE CONTROL

@ RECORDING INDICATOR @ TAPE SELECT SWITCHES

@ PLAYBACK INDICATOR @ REC- MUTE SWITCH

@ PAUSE INDICATOR @ EJECT BUTTON

® TAPE COUNTER @ PAUSE BUTTON

@ DIGITAL PEAK METERS STOP BUTTON

® RECORDING LEVEL CONTROL @ FAST FORWARD BUTTON

HEADPHONE SOCKET PLAYBACK BUTTON

@ MICROPHONE SOCKETS @ REWIND BUTTON

DOLBY NR SWITCH RECORD BUTTON

SAFETY PRECAUTION

The following precautions should be observed when servicing.

1. Since many parts in the unit have special safety-related characteristics, always use genuine Hitachi's replacement
parts. Especially critical parts in the power circuit block should not be replaced with other makes.
Critical parts are marked with Ain the schematic diagram, and circuit board diagram.

2. Before returning a repaired unit to the customer. the service technician must thoroughly test the unit to ascertain
that it is completely safe to operate without danger of electrical shock.

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT

STEREO CASSETTE TAPE DECK

February 1982 TOKAI WORKS

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D-EZZ l

SPECIFICATIONS

Semiconductors:

ICs: 4

Transistors: 7

Diodes: 7 (U, C, BS)

8 (FS, AU, W)

LEDs: 15
Track System: 4 track 2 channel stereo
Tape: Cassette tape (C-30, 60, 90)
Tape Speed: 4.75 cm/s

Recording System
and Bias Frequency:
Erasing System:

AC bias, 85 kHz
AC erase

Erase Ratio: 65 dB or more (at 1 kHz)
Frequency Response:
NOR-I: 20 Hz~15 kHz
30 Hz~14 kHz (:3 dB)
30 Hz~14 kHz*
Cr02~llz 20 Hz~16 kHz
30 HZ~15 kHz (:3 dB)
30 Hz~15kH2
METAL-IV: 20 Hz~17 kHz

30 Hz~16 kHz (:3 dB)
30 Hz~16 kHz"
S/N (Signal to Noise

Ratio):
Dolby NR ON: 66 dB (Weighted A, Reference
3% THD Metal Tape)
65 dB
Dolby NR OFF: 58 dB (Weighted A, Reference

3% THD Metal Tape)
57 dB*

Wow and Flutter: 0.05% (WRMS)

0.17%*
Input Sensitivity and
Impedance:
Microphone: 0.5 mV, 300 ohms ~5k ohms
Line in: 80 mV, 50k ohms or more

Record/Playback (DIN): 0.3 mV, 3k ohms (FS, AU, W)
Output Level: 500 mV
Output Load Impedance:

Line out: 50k ohms or more
Record/Playback (DIN): 50k ohms or more (FS, AU, W)

Headphone: 8 ohms~ 2k ohms
Distortion: 1.0% (1 kHz, 160 nWb/m)
Crosstalk: 60 dB or more (at 1 kHz)

30 dB or more (at 1 kHz)
AC 120V, 60 Hz (U, C)
AC 220V, 50 Hz (FS)
AC240V, 50 Hz (BS, AU)
AC 100-110V/115-127V/

Channel Separation:
Power Supply:

200-220V/230-250V,

50/60 Hz (W)
Power Consumption: 9W
Dimensions: 110(H) x 435(W) x 227(D) mm
Weight: 3.3 kg
Motor: Electronically controlled DC motor
Heads: Metal SL Record/playback head

Three-gap ferrite Erase head

According to DIN 45 500

DISASSEMBLY

. Cassette clear panel
1) Depress the eject button to open the cassette door.
2) Lift up the cassette clear panel in the direction of the
arrow (A) .
. Cassette door
Remove (two) nylon rivets.
. Upper cover
Remove © and ® (two) screws.
. Bottom cover
Remove ® , ©and ® (three) screws.
. Front panel
Remove ©(seven) screws.
. Main PC board
1) Remove ® and ® (two) screws and jack holder (D.
2) Lift up the front panel side of the PC board and pull
the PC board in the direction of the arrow@ .
. Cassette chassis
Remove ® (two) screws.
. Power PC board
Remove (I; (two) screws.

\

. O
Nylon rive-N :
=3