Akai GX-266D User manual

SERVICE MANUAL
PARTS LIST
worn GX-266D
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AKAI STEREO TAPE DECK
move. GX-266D
SECTION 1 SERVICE MANUAL
SECTION 2 PARTS LIST
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I. TECHNICAL
DATA
TRACK SYSTEM 4 track 2 channel stereo/monaural system
REEL CAPACITY Up to 7” reel
TAPE
SPEED
____7-1/2
and
3-3/4
ips.
(40.5%)
WOW & FLUTTER Less than 0.06% at 7-1/2 ips.
Less than 0.09% at 3-3/4 ips.
FREQUENCY
RESPONSE
30
to
25,000
Hz
+3
dB
at
7-1/2
ips.
using
LN
tape
30 to 19,000 Hz +3 dB at 3-3/4 ips. using LN tape
; 30 to 26,000 Hz +3 dB at 7-1/2 ips. using WR tape
30 to 20,000 Hz +3 dB at 3-3/4 ips. using WR tape
DISTORTION (1,000 Hz “0” VU) Less than 0.5% at 7-1/2 ips.
Less than 1.0% at 3-3/4 ips.
SIGNAL TO NOISE RATIO Better than 56 dB
(Measured via tape with peak recording level of +6 VU)
ERASE RATIO Better than 70 dB
BIAS FREQUENCY 100 kHz
HEADS
|
(6):
Two
GX
Playback
Heads,
Two
GX
Recording
heads,
Two
Erase
heads
MOTORS | (3): One AC Servo Capstan Motor
Two Eddy Current Reel Motor
F.F
&
Rewind
Time
90
sec.
using
1,200
ft.
tape
7
OUTPUT
JACKS
Line
(2):
0-0.775V
(MAX
0
VU)
required load impedance: more than 20 k ohms
Phone (1): 0—100 mV/8 ohms (MAX 0 VU)
INPUT
JACKS
Microphone
(2):
0.25
mV/2.4
k
ohms
required microphone impedance: 600 ohms
_
___|__Line
(2):
70
mV/100
k
ohms
SEMICONDUCTORS
Transistors:
61,
Diodes:
92
DIMENSIONS
404
(W)
x
470
(H)
x
250
(D)mm,
(15.9
x
18.5
x
9.8”)
cr
-
sells
ae
250(D)mim
With
Wood
Side
Plate
WEIGHT | 18.3 kg (40.4 Ibs.)
:__20.6 kg (45.5 Ibs.) : With Wood Side Plate
"POWER
REQUIREMENTS
___110/120/220/240V,
50/60
Hz
Switchable
* For improvement purposes, specification and design are change without notice.

i.
DISMANTLING
OF
UNIT
In
case
of
trouble,
etc.
necessitating
disassembly,
please
disassemble
in
the
order
shown
in
photographs.
Reassemble
in
reverse
order.
HEAD COVER:
PINCH ROLLER CAP
Eo oo F be
SCREWS
CONTROL
KNOB
&
SWITCH
KNOB
UPPER PLATE
c
SIDE 4
TENSION
PLATE
ARM
e
PINCH
ROLLER
SCREWS
MACHA PANEL
BOTTOM PLATE
SCREWS
AMP PANEL OPERATION PANEL
SCREWS
REAR PLATE
SCREWS

li. CONTROLS
Q@O@@® @®© QCOOCW!®
1. INDEX COUNTER AND RESET BUTTON
. PINCH ROLLER
HEAD COVER
. SUPPLY REEL TABLE
REEL RETAINER
TAPE GUIDE (SENSING POLE: FORWARD-REVERSE)
- TENSION ARM
8. PAUSE LEVER (PAUSE)/REC MUTE OFF
. REVERSE SELECTOR (REV SELECTOR)
. POWER SWITCH (POWER)
. RECORDING MUTE SWITCH/TIMING LAMP
. VU METER (FOR LEFT CHANNEL)
. VU METER (FOR RIGHT CHANNEL)
MONITOR SWITCH (MONITOR)
. HEADPHONE JACK (PHONES)
MONITOR TMeR BTART
PAL
rare Ss
YAPa | Tape —AEC-— armas tend}
SPHEO SELECTOR vary Alcor ur ed
Low Pa
16,
17,
18.
19.
20.
. TENSION ARM (SENSING POLE: REVERSE>FORWARD)
. OPERATION BUTTONS
. MEMORY MARKER (FOR LINE-IN)
. MEMORY MARKER (FOR MIC-IN)
. MICROPHONE INPUT CONTROLS (REC LEVEL-MiC
. LINE INPUT CONTROLS (REC LEVEL-LINE)
- MICROPHONE JACK (MIC)
. RECORDING LEVER (REC)
. TAPE SELECTOR
. TAPE SPEED SELECTOR
S8SBNSREESKS
COQ OOO @O OO @
LINE OUTPUT/HEADPHONE OUTPUT CONTROLS
(LINE OUT-PHONES)
TIMER START SWITCH (TIMER START)
REEL RETAINER
TAKE-UP REEL TABLE
TAPE GUIDE

IV.
= [=]
PON AHRAWN om
. PINCH ROLLER MICRO SWITCH SW-905
PINCH ROLLER PLUNGER SOLENOID SL-3
PAUSE MICRO SWITCH SW-903 & SW-907
TENSION MICRO SWITCH SW-904
MUTE SWITCH P.C BOARD NE-2228
BRAKE PLUNGER SOLENOID SL-901
BRAKE MICRO SWITCH SW-906
. REEL MOTRO MICRO SWITCH SW-908
. HEAD BLOCK
. RIGHT REEL MOTOR 24X0-MR
11.
12.
13.
14,
15.
16.
17.
18.
19.
PRINCIPAL
PARTS
LOCATION
Rear View
OPERATION
P.C
BOARD
NE-2239
MIC
AMP
P.C
BOARD
NE-5223
AMP P.C BOARD NE-5222
POWER
TRANSFORMER
NET-11
LEFT
REEL
MOTOR
24X0-MR
VOLTAGE
SELECTOR
SYSTEM
CONTROL
P.C
BOARD
NE-1213
CAPSTAN
MOTOR
SCM2-24KJ
REV
PLUNGER
SOLENOID
SL-902

V. MECHANISM
PINCH ROLLER
MICRO SWiTCH SW905
QUICK PLATE
Fig. 1
I. PINCH ROLLER POSITION ADJUSTMENT
AT STOP MODE (Refer to Fig. 1)
1) Remove head block.
2) Adjust Stopper so that the clearance between
Pinch Roller and Capstan Shaft is 10mm.
Fig. 2
2. POSITION ADJUSTMENT OF PINCH ROL-
LER SOLENOID SL-3 (Refer to Fig. 2)
1) Remove head block.
2) Insert a 4.2 mm gauge (a U type washer etc.)
between the P Plunger Lever and P Joint (Refer to
Fig. 3).
3) Set the deck to playback mode and fix Pinch
Roller Solenoid at position at which the pinch
Roller begins to rotate.
3. PINCH ROLLER PRESSURE ADJUSTMENT
(Refer to Fig. 3)
Adjust Pinch Roller Pressure Adjustment Nut so that
pinch roller pressure is 1.2 kg.
4, POSITION ADJUSTMENT OF QUICK PLATE
(Refer to Fig. 1)
Adjust Quick Plate position so that at stop mode,
the Pinch Roller Microswitch operates properly, and
the Quick Plate does not strongly hit against the body
of the microswitch.
ADJUSTMENT
PINCH ROLLER PRESSURE
ADJUSTMENT NUT —
1.3 to 1.4 kg
P PLUNGER LEVER
5. POSITION ADJUSTMENT OF BRAKE
SOLENOID SL-1 (Refer to Fig. 4)
Set the deck to playback mode, and fix Brake
Solenoid at position at which the left and right brake
levers display 180° angle relativity.
6. POSITION ADJUSTMENT OF BRAKE
MICROSWITCH SW-906 (Refer to Fig. 4)
Set the deck to playback mode, and adjust Brake
Solenoid Microswitch position so that the micro-
switch operates properly.
7. BRAKE TENSION ADJUSTMENT (Refer to
Fig. 4)
Adjust Spring Stopper position so that the brake
tension is 350 to 500g.
BRAKE SOLENID SL-1
REEL MOTOR BRAKE MICROSWI'cH
Soe sooe MICROSWITCH Sw908 SwoE
i
PAUSE MICROSWITCH
SW-903, SW-307
PAUSE SUDE 0.3405 mm

8. PAUSE ADJUSTMENT (Refer to Fig. 5)
1) At playback mode, lock Pause Lever.
2) Adjust Pause Lock Plate position to obtain a 0.3
to 0.5 mm clearance between Pinch Roller and Cap-
stan.
3) When making this adjustment, be careful that the
clearance between Pinch Roller and Capstan does
not exceed 0.5 mm.
4) Confirm that the Quick Tension Microswitch is
pushed when the Pause Lever is depressed and if
not, adjust with QT Lever B.
pHs SUPPORT ANGLE
t O.tmm
CAPSTAN eal
|
|
¥.
<<
ae
{OI}
2
ADJUSTMENT WASHER
CAPSTAN SHAFT: |
Fig. 6
TANSION MICRO SWITCH SW-904
Fig. 7
FIXATION SCREW
PIPE EL LO LIL ORCL LILEL ED
(iF
9.
CAPSTAN
SHAFT
LOOSE
PLAY
ADJUST-
MENT
(Refer
to
Fig.
6)
Adjust
to
obtain
a
clearance
of
about
0.1
mm
between
the
capstan
shaft
and
thrust
support
angle.
10.
OPERATING
POSITION
ADJUSTMENT
OF
TENSION
MICROSWITCH
SW-904
(Refer
to
Fig.
7)
Adjust
Tension
Microswitch
position
so
that
when
the
Tension
Arm
drops,
the
microswitch
operates
perfectly
to
effect
stop
mode.
TAPE GUIDE
te, TAPE
TENSION ARM
ADJUSTMENT WASHER
* LOWER THE GUIDE DOWN A LITTLE
ADJUSTMENT WASHER
XLFT THE GUIDE UPA LITTLE
Fig. 8
11.
TAPE
GUIDE
HEIGHT
ADJUSTMENT
(Refer
to
Fig.
8)
1)
Adjust
Tape
Guide
height
so
that
the
tape
does
not
curl
between
tape
guides
on
Head
Base.
2)
In
case
the
tape
guide
is
low,
adjust
by
inserting
a
U
Type
Washer
on
the
right
side
in
Fig.
8,
and
in
case
it
is
high,
adjust
by
inserting
a
washer
on
the
left
side.
12.
REEL
TABLE
HEIGHT
ADJUSTMENT
(Refer to Fig. 9)
1)
Load
a
tape
and
sét
the
deck
to
F.FWD
and
REV
modes.
Adjust
Reel
Table
height
so
that
the
tape
winds
on
the
center
of
the
reels
at
both
modes.
2)
Tape
should
wind
on
center
of
reel
regardless
of
type
of
reel
used.

Vi.
HEAD ADJUSTMENT
TAPE GUIDE HEIGHT ADJUSTMENT NUT REV
PLAYBACK RECORDING ERASE
HEAD HEAD HEAL
Fie clis sta
tar260
Re-240
©
(pazeo
Fig.
10
:
Test.
Tape
Adjustment
Step
|
Adjustment
ca
Supply
Signal
Mode
Point
Remarks
|
ee
——
.
Tape
Guide
1)
Adjust
so
that
tape
travels
|
1
Tape
Guide
Optional
FWD
Height
smoothly
and
does
not
twist.
Height
Adjustment
2)
Do
not
thread
tape
over
tension
Nut
arm.
.
Upper
edge
of
channel
1
head
core
FWD
Erase
‘ .
2
:
Optional
FWD
A\(B\C
is
0.1mm
higher
than
upper
edge
Head
Height
P
(ABYC)
of
tape.
FWD
Recording
.
Upper
edges
of
channel
1
head
core
3
Head
Height
Optional
(DXE)(F)
and
tape
are
the
same
height.
FWD
Playback
;
Upper
edges
of
channel
1
head
core
4
Head
Height
Optional
(GH)
and
tape
are
the
same
height.
=i
|
FWD
Playback
8,000
Hz
|
§
Head
Azimuth
3-3/4
ips
FWD
qd)
|
Maximum
output,
both
channels,
Alignment
Test
Tape
Adjust
head
gap
surface
so
that
FWD
Playback
8,000
Hz
there
is
no
change
in
output
level
6
Head
Gap
3-3/4
ips
FWD
(K)
when
tension
is
applied
to
the
sup-
Alignment
Test
Tape
ply
reel
side
‘|
FWD
Recording
|
Scotch
#211
Tape,
r
i
|
7
Head
Azimuth
15,000
Hz
REC
(F)
|
Maximum
output,
both
channels,
Alignment
—20
dBm
;
Adjust
head
f
that
FWD
Recording
|
Scotch
#211
Tape,
sles.
is
-
ree
or
sid
eel
8
Head
Gap
15,000
Hz
REC
@)
when
tension
is
applied
to
the
sup-
Alignment
—20
dBm
|
ply
reel
side,
Chart
1
NOTES:
1)
As
perfect
head
adjustments
are
vital
to
tape
deck
performance,
be
sure
that
these
adjustments
are
carried out properly.
2)
Be
careful
not
to
use
a
magnetized
driver
or
other
magnetized
tools
in
the
vicinity
of
the
heads.
3)
Use
only
new
tape
as
level
variation
is
likely
to
occur
when
using
old
tape.
4)
Demagnetize
heads
with
head
demagnetizer
before
and
after
head
adjustment.
5) Set tape speed to 7-1/2 ips except.
6)
Adjustments
outlined
in
Chart
1
are
only
for
FWD
side
heads.
However,
adjustments
for
REV
side
heads
are
exactly
the
same.

Vit.
ELECTRICAL
ADJUSTMENT
1. DC POWER SUPPLY AND TAPE SPEED ADJUSTMENT
Seika Mian SP: Sat sah tise iia Saha 89 Pinte cairo 12%
VR-1 1kB_ DC Voltage Adj.
VR-2 50kB 3-3/4 ips Tape Speed Adj.
VR-3 10kB 7-1/2 ips Tape Speed Adj.
VRI
VR3
VR2
Fig. 11
Adjustment .
Step
Item
Mode
Adjustment
Point
Result
Remarks
= == 4
1
DC
Voltage
|
Stop
VR-11kB
24.0V
Measured
at
TP-1
on
Sys.
Con
P.C
Board
3-3/4
ips
500
Hz
1,000
Hz,
7-1/2
ips
Test
Tape.
2
Tape
Speed
FWD
VR-2
50
kB
£0.5%
Tape
Speed
3-3/4
ips.
7-1/2
ips
1,000Hz
1,000
Hz,
7-1/2
ips
Test
Tape.
3
Tape
Speed
FWD
VR:3
10
kB
40.5%
Tape
Speed
7-1/2
ips.
Chart 2