Akai X 360 Service Manual

Page 2

I. SPECIFICATIONS

POWER SUPPLY : AC 100 to 240 V, 50 or 60 Hz
RECORDING SYSTEM

In-line 4-track stereo, monaural recording

by using Cross-field Bias Head.
TAPE SPEED : 1-7/8, 3-3/4, 7-1/2 and 15 ips.
TAPE SPEED DEVIATION
Within $0.591: at 7-1/2 ips
Within 1' 1.0% at 34/4 ips
Within 11.0% at 1-7/8 ips
WOW AND FLUTTER
Less than 0.10% r.m.s. at 7»1/2 ips
Less than 0.13% 1.11115. at 33/4 ips
Less than 0.25% r.m.s. at 177/8 ips
FREQUENCY RESPONSE
30 to 21,000 Hz :3 dB at 7-1/2 ips
301018000 Hz i 3 dB at 3-3/4 ips
40 to 9,000 Hz i4 dB at 1~7/S ips
SIGNAL T0 NOISE RATIO
(at Line Output) : Greater than 48 dB at 7»I/2 ips
Greater than 45 dB at 3-3/4 ips
Greater than 48 dB at 1-7/8 ips
TOTAL HARMONIC DISTORTION
(at Line Output, 1,000 Hz 0 VU Rec/PB)
Within 1.7% at 7-1/2 ips
Within 3.0% at 3-3/4 ips
Within 3.0% at 1»7/8 ips
RECORDING INPUTS
MICROPHONE : Above 017 mV

LINE INPUT : Above 70 mV
Impedance . . . 166 K ohms
DIN INPUT : High : 70 mV 166 K ohms

Low: 7 mV 16 K ohms
OUTPUTS
LINE OUTPUT : Required Load Impedance :
more than 50,000 ohms
1.23 V (+4 db: 1 1.5 db) at 7-1/2 ips

1.03 V (+2.5 dbs i 1.5 db) at 3-3/4 ips
0.82 V (+0.5 dbs $1.5 db) at 1-7/8 ips

POWER OU'IIU'I': External Speaker Jack

More than 10 W at 8 ohms Non-inductive

resistance
NOISE ; Less than 5 mV at 8 ohms at External
Speaker Jack

(Volume Control at Minimum position)

FAST FORWARD AND REWIND TIME
' 75 seconds for a full 1,200 foot tape

at 50 Hz
60 seconds [or a full 1,200 foot tape
at 60 Hz

CROSS»TALK : Less than ~70 dB (Monaural)
Less than -43 dB (Stereo)

ERASE RATIO More than 70 dB

INSULATION DURABILITY
500 V AC for more than one minute
duration

BIAS FREQUENCY: 100 KHz

MAIN MOTOR

REEL MOTOR

HEADS
PLAYBACK HEAD

RECORDING HEA

ERASE HEAD

Hysteresis Synchronous 3 speeds
(2-4-8 pole) motor.
Condenser Capacity 3 ME (50 Hz), 2 14F
(60 Hz)
Revolutions :
3,000~ 1 ,5007750 r.p.m. (50 Hz)
3,600e1,800-900 rpm. (60 Hz)
Two 6-pole eddy current outer-rotor
motors
Revolutions :
930 r.p.m. at 50 Hz, 100 V
1,120 r.p.mi at 60 Hz, 120 'V

In-Iine 4-track stereo and monaural
Impedance . . . 5,000 ohms at 1,000Hz
Gap . . . 2 microns

D
In-Iine 4-track stereo and monaural
Impedance. . . 45 ohms at 1,000 Hz
Gap . , . 2 microns
In-Iine 4~track stereo and monaural
Impedance . 1 .380 13th at 100 KHz
Gap . . . 0.4 mm

CROSS-FIELD BIAS HEAD

In-line 4»track stereo and monaural
Impedance. 1 i 430 ohms at 100 KHz
Gap . . . 0.4 mm

INTERNAL SPEAKERS

TRANSISTORS USED

DIODE USED

2 4iinch Round Speakers
Nominal Power Input . . , 3 W, 16 ohms

15 ZSC458LG®/©

25C372

ZSC828@

25C538A©

ZSCGSD® X-JGOD (without
ZSC728 Main Amplifier)
25137511 4 °'
2SB77A®

2513157

2313147

28C828R

ZSCS 38RQ Main Amplifier
zscsmzs 16 ea.
25013011

1N34A

10132

1004

10D6

5132

SL450

SL-lSOd

IN759A

RD»24A

u:

ND-h-hNQHJhJ-lI-nI-ildwt-I

I

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I-NNNb-OI-n

Page 9

V. MAGNETIC HEADS ADJUSTMENT

1. Adjustment of Magnetic Heads

1},
«p
7

Fig. 1

Jun screws to a... the an. m: at
m: upper um i; m: same my as the

_1zs~a,rsmm upper gas. or m: m...

Since adjustment of the Heads critically affects tape
recorder performance, it is essential that Heads be
carefully adjusted with precision measuring equipment
and a suitable recorded tape.

1.] Adjustment of Head Height (See Figlres l and 2)
Whenever replacing the Head Assembly, adjust the
Tape Guides (J) and (K) so that they do not contact
the edge of the tape, then proceed with Head
height adjustment.

1) Playback Head
To adjust, turn Screw (a) (Figure 1) during
Normal Play position so that the upper edge
of the upper core of the Playback Head is the
same height as the upper edge of the tape.
Adjust by turning Screw (b) (Figure 1) during
Reverse Play position so that the lower edge
of the lower core of the Playback Head is the
same height as the lower edge of the tape.

2) Recording Head
Adjust with Screws (d), (e) and (f) (Figure 1) so
that the upper edge of the upper core is the
same height as the upper edge of the tape.

3) Erasing Head
Adjust Screws (g), (h) and (i) (Figure I) so that

the upper edge of the upper core is 0.125 to
0.15 mmhigher than the upper edge of the tape.
(Precaution)

In adjusting Head Height, make sure that the
front of the Head is at right angles to the
Chassis and that the upper and lower part of
the Head firmly contact the tape.

1.2 Adjustment of Azimuth Alignment

1) Playback Head
Use a Pre-recorded tape (16 KHz, 7-1/2 ips),
and connect ahighly sensitivity V.T.V.M. to the
line output jack. Adjust Screw (C) (Figure 1) so
that line output voltage is maximum

2) Recording Head
Connect an Audio Oscillator to the line input
jack and record 16 KHz Signals at a -10db
recording level and depress the Monitor TAPE
Button. Adjust Screw (t) (Figure 1) so that the
indicated V.T.V.M. value applied to the line
output jack is maximum.

3) Erasing Head
Visually check to assure that the centerline of
the Erasing Head, is at right angles to the Head
Chassis.

4) Bias Head
Loosen Screws (m) and (11) (Figure 1), adjust
angulation and clearance of the Bias and
Recording Heads, as subsequently described in
paragraph 2-5 (Adjustment of Recording
Equalization (Balance) Characteristics).

Page 23

NORMAL PLAY

' mm mam

a: a 35...: rain

sax:

22

Page 71

REPLACEMENT PARTS TABLE

X~360 PARTS LIST

HEAD BLOCK

CAPSTAN & PINCH WHEEL BLOCK

STABILIZER BLOCK

CYCLE CHANGE BLOCK

MECHANISM CHASSIS

REEL MOTOR & TABLE BLOCK

REVERSE MECHANISM BLOCK

MAIN MOTOR BLOCK

BRAKE BLOCK

RESISTOR BLOCK

RELAY BOARD BLOCK

POWER SOURCE BLOCK

POWER SOURCE PRINTED BOARD

OSCILLATOR BOARD

DM DETECTOR BOARD

PLAYBACK PRE-AMPLIFIER BOARD

RECORDING AMPLIFIER BOARD

MAIN AMPLIFIER BOARD

MONITOR SWITCH BOARD

TRACK SELECTOR BOARD

C.0M. DETECTOR BOARD

C.0.M. SET SWITCH BLOCK

C.O.M. MECHANIC BLOCK

SPARK QUENCHER & SWITCH BLOCK

SPEED SELECTOR SWITCH BLOCK

AMPLIFIER CHASSIS BLOCK

CASE & PANEL BLOCK ,

HEADPHONE CONNECTION BOARD
(X-360D only)

CHASSIS PRINTED BOARD

MAIN AMPLIFIER SOCKET BORD

RD-l 50B ............ 32
RD-l 39B ............ 33
RD-2300 ............ 34

RD-2500

RD-524
RD-S 2 6
RD-532

Page 102

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t
i
1
I
I
2

SPARK QUENCHER & MICRO SWITCH BLOCK (RD-1508)

MICRO SWITCH BLOCK (RD-15013)

Nomenclature

Spark Quencher and
Micro Switch Assembly
Complete
Micro Switch V-1A44
Actuator for Micro
Switch
Shaft 3 x 55 mm (Micro
Switch Mounting)
Metal Sleeve, Micro
Switch Mounting
6 x 7 mm

SPARK QUENCHER &
Raft No. Part: No
RD-ISOB
I RD-ZOI l
_ 2 RD-2012
3 RID-2013
4 R0401
S RD-2OIS

E Ring 1.9 mm

Ref. No.

6

7

ID

Parts No.
RD~201 6

SKSO-l

PSO-I

550-1

RD-2017

Nomenclature

Spurk Quencher Block
(RD-150)
Spark Quencher
Compound
0.1 ,4 + 120 9
Prop (hex) for
Printed Circuit Board
Screw, binding head
3 x 5 mm
Bracket, Micro Switch
Mounting

32