Akai 1730 SS 1730 DSS Service Manual

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TABLE OF CONTENTS

SPECIFICATIONS ............................... Z
MEASURING METHODS ......................... 3
CONTROL LOCATIONS .......................... 5
DISMANTLING OF TAPE TRANSPORT UNIT

& AMPLIFIERS ................................ 6
TRANSPORT MECHANISM ....................... 8
MECHANISM ADJ USTME NT ....................... 12
AMPLIFIER ADJUSTMENT ....................... 14
MAINTENANCE PROCEDURES ................... 16
TROUBLE SHOOTING CHART ................... l7
COMPOSITE VIEWS OF COMPONENTS ............. 22
SCIIEMATIC DIAGRAM

When placing order for parts, please use Separate
PARTS LIST or PRICE LIST FOR PARTS.

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Symptom

Trouble

Considerable difference between left and

right levels during playback

l.

Playback level out of adjustment

2. Recording Problems (Unit plays back pre-recorded tapes satisfactorily but recording unsatisfactory).

Symptom

Trouble

Does not record (4 ch or 2 ch)
(No VU meter indication)

(VU meter indication normal)

bun--

No-

VU meter itself or lead wire defective

Defective input jack

Transistor TR~101 defective

lC-lOl (LB-3141) defective

Rec/play chenge switch (SW 10) defective

Components of oscillator circuit or oscillator coil defective

3. Recording head defective

Sound distorted

(VU meters function normally. Recording

Faulty recording bias circuit

monitor through headphones also normal). 2. Fautly recording equalization circuit
3. Dirty head
(VU meter function normally, 1. Over-recording input
but recording monitor through headphones 2. Defective input equipment
abnormal) 3. Check recording amp card (LF75013)
Fautly erasing (4 ch or 2 ch)
(Does not erase at all) 1. Erase head defective
2. Disconnected erase head wire. Excessive amount of dust adhering
to head surface
(Incomplete erasure) l. Erasing bias voltage low
(TR-501, 502 ; oscillator coil or Erase Head defective)
Erasing noise
(Popping noise) 1. Defective recording tape
2. Transistor 'l'R--501, 502 defective
3. Head magnetized
Recording sensitivity low
(VU meter functions normally) 1. Dirty head
2 Bias voltage out ofadjustment
3. Transistor TR~501, 502 defective
4. Tape itself defective
(UV meter does not indicater properly) 1. Loose input jack connection
2. VU meter sensitivity low
3. Recording level out of adjustment
Sound fades or drops out 1. Dust adhering to the head surface
2. Tape itself dirty
3. Back tension too weak
4. Recording bias voltage too low
5. Head worn
Considerable difference between left and . Large deviation from line VR(RV1 ~4) curve
right levels when recording 2. Recording level out ofadjustment

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