Hitachi D-E25 User Manual

Tk || Ne. 1445e
D-E25
©) HITACHI
(U, C, FS, BS, AU, W)
SERVICE MANUAL
Use
this
manual
together
with
the
ML-1
mechanism
Technical
Information
(No.1473).
HITA-00383
©
@
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©
®
CONTENTS
SPECI
CATIONS
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DiSASSOMDIY ..............ccessssssenssressccesassassensateseeanoeereneres 2
AGIUSTMOGNT saisdicsmdecepcavensetreicciemste nie ent 3
Inspection of MEChHANISM........... cc seeeteecreeteeeenes 4
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Schematic
diagram
...........cccssecsesssseecetessnecneceenerees
5
Circuit
board
diagram...........ceceesssececeeeeneaeeeneens
7
Exploded
view
(Cabinet)................::csccessssseneceeeeeees
10
Replacement parts list ............ cscs eeceeeeenecesseeens 11
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KEY TO ILLUSTRATIONS
1. Power (Mains) switch 10. Dolby NR switch
2, Playback indicator 11. REC Mute switch
3. Tape counter 12. Eject button
4. Recording indicator 13. Pause button
5. Level indicators 14. Stop button
6. Recording level controls 15. Fast forward button
7. Headphone socket 16. Playback button
8. Microphone sockets 17. Rewind button
9. Tape select switches 18. 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
replaemeent
parts.
Especially
critical
parts
in
the
power
circuit
block
should
not
be
replaced
with
other
makes.
Critical
parts
are
marked
with
A\in
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.
Printed by: Schaltungsdienst Lange, Berlin (Germany)
SPECIFICATIONS
AND
PARTS
ARE
SUBJECT
TO
CHANGE
FOR
IMPROVEMENT
STEREO
CASSETTE
TAPE
DECK
December
1980
TOKAI
WORKS
LE ae A RE AL TS, eT RTE EAN eee PE ALE ae TEE RE EAN Se oe ree eh se Tw ea on

Hitachi D-E25 Specifications

General

Track System	4-track, 2-channel stereo
Total Harmonic Distortion	1.0%
Type	Cassette Deck
Heads	1 x record/playback
Motor	DC motor
Tape Type	Normal, CrO2, Metal
Power Supply	AC 220V, 50Hz

Summary

Safety Precautions

Specifications

Disassembly

Cassette door

Remove the cassette door by lifting it after pressing the eject button.

Upper cover

Remove the four screws securing the upper cover.

Bottom cover

Remove the two screws securing the bottom cover.

Front panel

Remove front panel knobs and six screws.

Cassette chassis

Remove the two screws securing the cassette chassis.

Adjustment

Tape speed

Adjust tape speed using the variable resistor for correct playback.

Head azimuth

Adjust head azimuth for optimal playback signal alignment.

Playback gain

Adjust playback gain to achieve specified output levels on the LINE OUT jacks.

Level indicator

Adjust level indicators to show 0 dB for a specific input signal level.

Bias leakage

Adjust bias leakage to ensure correct bias frequency.

Bias current

Adjust bias current for optimal recording bias voltage.

Record/playback output level

Adjust output level for correct recording and playback signal indication.

Dolby NR

Adjust Dolby NR circuit for proper signal boost.

Inspection of Mechanism

Lubrication

Rotary section

Lubricate rotating parts like the motor and sliding points.

Sliding section

Lubricate sliding parts like the chassis and mechanism.

Spring resonance prevention

Apply lubrication to prevent spring resonance issues.

Schematic Diagram

Circuit Board Diagram

Exploded View (Cabinet)

Replacement Parts List