Akai head rush e2 User manual

SERVICE MANUAL 1
TAP DELAY / TAPE ECHO SIMULATOR / LOOPING RECORDER

SERVICE MANUAL
2
SAFETY INSTRUCTIONS INFORMATIONS
1. Parts identified by the symbol are critical for safety.
Replace them only with the parts number specified.
2. In addition to safety, other parts and assemblies are
specified for conformance with such regulations as those
applying to spurious radiation.
These must also be replaced only with the specified
replacements.
Examples : Noise blockingcapacitors,noiseblocking filters,
etc.
3. Use specified internal wiring. Note especially :
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads
4. Use specified insulating materials for hazardous live parts.
Note especially :
1) Insulation Tape
2) PVC tubing
3) Spacers (insulating barriers)
4) Insulation sheets for transistors
5) Plastic screws for fixing micro switches
5. When replacing AC primary side components (trans-
formers, power cords, noise blocking capacitors, etc.),
wrap the ends of the wires securely around the terminals
before soldering.
6. Make sure that wires do not contact heat producing parts
(heat sinks, oxide metal film resistors, fusible resistors,
etc.).
7. Check that replaced wires do not contact sharp edged or
pointed parts.
8. Also check areas surrounding repaired locations.
9. Make sure that foreign objects (screws, solder droplets,
etc.) do not remain inside the set.
SAFETY CHECK AFTER SERVICING
After servicing, make measurements of leakage-current or
resistance in order to determine that exposed parts are
acceptably insulated from the supply circuit. The leakage-
current measurement should be done between accessible
metal parts (such as chassis, ground terminal, microphone
jacks,signal input/output connectors, etc.) andthe earthground
through a resistor of 1500 ohms paralleled with a 0.15 F
capacitor, under the unit’s normal working conditions.
The leakage-current should be less than 0.5 mArmsAC. The
resistance measurement should be done between accessible
exposed metal parts and power cord plug prongs with the
power switch (if included) “ON”. The resistance should be
more than 2.2 M ohms.
SYMBOLS FOR PRIMARY DESTINATION
Unit destinations are indicated with letters as shown below.
Symbols Principal Destinations
A U.S.A
B England
E Europe
J Japan
VGermany
X1 Japan
X4 Universal Area
MAKE YOUR CONTRIBUTION TO PROTECT THE
ENVIRONMENT
Used batteries with the ISO symbol for recycling as
well as small accumulators (rechargeable batteries),
mini-batteries (cells) and starter batteries should not
be thrown into the garbage can.
Please leave them at an appropriate depot.
PRECAUTIONS FOR LITHIUM BATTERY
The lithium battery may explode when
incorrectly replaced.
[OBSERVE THE FOLLOEING WHEN REPLACING]
 Replace with the same make and type or equivalent recom
mended by manufacturer.
 Place battery in correct polarity.
 Do not short the terminals.
 Do not charge battery.
 Do not dispose of battery in fire.

SERVICE MANUAL 3
* The specifications are subject to change without the prior notice.
I. SPECIFICATIONS
Connectors
INPUT(Inputimpedance:500kohmsormore)
MIXOUT(Outputimpedance:1kohmsorless)
HEAD1/EFFECT-HEAD4 (Outputimpedance:1kohms)
DC IN(9Volts)
Controls
LEVEL, HF DAMP, FEEDBACK, TIME COARSE/TIME, TIME FINE/HEAD GAP,
RATIO, MODESELECT, LOOP LEVEL, LOOP TIME, FOOTSWITCHx2
Indicator
MODELED x3, EFFECTON/OFF x1, TEMPO x 1
Functions
Mode:NORMALDELAY,TAPE ECHO,LOOPINGRECORDER
SamplingRate:44.1kHz(2 9.4kHzin LOOP TIM:EXT END)
SamplingResolution :16 bitlinear
DelayTime: NORMALDELAY=23.8 sec.,TAPE ECHO =5.9 sec
RecordingTime:LOOPINGREC=23.8 sec.(11.9 sec,in over-dub),
EXTEND = 35.6sec. (17.8sec. inover-dub)
Power
requirements
9V DC/160mA, AC-adaptor
Dimensions
140 (W) x183.5(D) x 65 (H) mm
Weight
1150g
Accessories
Operator's Manual, AC-adaptor

SERVICE MANUAL
4
II. DISASSEMBLY
Incaseoftrouble,etc.,necessitatingdismantling,pleasedismantleintheordershownintheillustrations.Reassembleinthe
reverse order.

SERVICE MANUAL 5
III. PARTS LIST
HOW TO USE THIS PARTS LIST
1. This Parts List lists those parts which are considered necessary for repairs.
2. Parts not shown in the Parts List will not in principle be supplied.
3. How to read the Parts List.
WARNING
INDICATES SAFETY CRITICAL COMPONENTS. FOR CONTINUED SAFETY, REPLACE SAFETY CRITICAL
COMPONENTS ONLY WITH MANUFACTURER'S RECOMMENDED PARTS.
AVERTISSEMENT
IL INDIQUE LES COMPOSANTS CRITIQUES DE SÉCURITÉ. POUR MAINTENIR LE DEGRÉ DE SÉCURITÉDE
L'APPAREIL, NE REMPLACER QUE DES PIÉCES RECOMMANDEES PAR LÉ FABRICANT.
1. PC MAIN BOARD BLK
Ref. No. Part No. Description
D5 ED-431276C D SCHOT 1S30-J T05
D110 ED-431276C D SCHOT 1S30-J T05
:
:
IC5 EI-811073J ICTRC-6593
IC10 EI-811068J IC HD74HC157FP
Service parts classification
These reference symbols correspond with component
symbols in the Schematic Diagrams.
2. FINAL ASSEMBLY BLK
Ref. No. Part No. Description
1. SA-349332 FOOT
2. ZS-344754C ST PAN30x06STL CMT
:
:
44. SP-417333J COVER TOP
45. ZS-418385J BT BID30X06STL BNI EATRH LOCK
46-A EW-380905J AC CORD 250S KP300 KS16A
H B J [J]
46-B EW-368420J1 AC CORD 200SKP30KS B AC [A]
46-C EW-410608J AC CORD 250 KP4819D KS31A B E
[E,V]
Symbols for primary destination
[A] U.S.A. [J] Japan
[B] England [V] Germany
[E] Europe [x1] Japan
[X4] Universal Area
Safety critical component
This number corresponds with the individual parts index number
in the figure.
ATTENTION
1. When placing an order for parts, be sure to list the Part No., Model No. and the description of each part.
Otherwise, the non-delivery of the part or the delivery of a wrong part may result.
2. Please make sure that Part No. is correct when ordering.
If not, a part different from the one you ordered may be delivered.
3. Since the parts shown in Parts List or Preliminary Service Manual may have been the subject of changes,
please use this Parts List for all future reference.

SERVICE MANUAL
6
1. PC BOARD BLK
Ref.No. Part No. Description
1 BA L8024A020A PC(#) MAIN BLK E2
PC(#) MAIN BLK E2 CONSISTS OF FOLLOWING PC BOARDS.
* PC MAIN BLK
* PC OPERATION BLK
2. PC MAIN BLK
Ref.No. Part.No. Description
IC1 EI 822043X IC HD6433641RC21H
IC2 EI 811878J IC AK7712A-VT
IC3 EI 822044X IC MSM5117800D-60JS
IC4 EI 810386J IC HD74HC174FP
IC5 EI 811068J IC HD74HC157FP
IC6 EI 428017J IC HD74HC74FP
IC7 EI 821831X IC DS1811R-10
IC8 EI 822042X IC NJM78M05DL1A FPTE1T16E
IC101 EI 810573J IC NJM2904M FPT1T12E
IC102 EI 810573J IC NJM2904M FPT1T12E
IC103 EI 810826J IC NJM4558M FTP1T32P
IC104 EI 810826J IC NJM4558M FTP1T32P
IC301 EI 810826J IC NJM4558M FTP1T32P
J1 EJ 812072J SOCKET DC HTJ-020-05A 1P
J301 EJ 812069J PHONE J HTJ -064-13H 6.3
J302 EJ 812069J PHONE J HTJ -064-13H 6.3
J303 EJ 812069J PHONE J HTJ -064-13H 6.3
J304 EJ 812069J PHONE J HTJ -064-13H 6.3
J305 EJ 812069J PHONE J HTJ -064-13H 6.3
J306 EJ 812069J PHONE J HTJ -064-13H 6.3
TR301 ET 822052X TR FET CHIP 2SK930 D
TR320 ET 433072J TR C.DTC114TKA T146T08E
TR321 ET 433072J TR C.DTC114TKA T146T08E
TR322 ET 433072J TR C.DTC114TKA T146T08E
TR323 ET 429896J TR C.DTA144EKA T146T08E
TR324 ET 430868J TR C.DTC114EKA T146T08E
TR325 ET 430868J TR C.DTC114EKA T146T08E
X1 EI 812081J OSC X'TAL HC-49/U-S 16.9344MHZ
3. PC OPERATION BLK
Ref.No. Part.No. Description
100 SE 822244X SPACER LED LEDH-9 L=9
200 SE 822048X SPACER LED LEDH-13 L=13
D1 ED 386225J D SILICON 1N4002 T26 100/1.0A
D201 ED 812086J D LED L- 934SGD GREEN
D202 ED 812086J D LED L- 934SGD GREEN
D203 ED 813021J D LED L- 934SYD YELLOW
D204 ED 812087J D LED L- 934SRD - G RED
D205 ED 812087J D LED L- 934SRD - G RED
SW201 ES 349474 SW TACT SKHHAM004A
SW202 ES 821283X SW SLIDE SSSU011700
SW203 ES 821283X SW SLIDE SSSU011700
VR201 EV 812076J VR ROTARY RK09L1140 L12.5 B103
VR202 EV 812076J VR ROTARY RK09L1140 L12.5 B103
VR203 EV 812076J VR ROTARY RK09L1140 L12.5 B103
VR204 EV 812076J VR ROTARY RK09L1140 L12.5 B103
VR205 EV 812076J VR ROTARY RK09L1140 L12.5 B103
VR206 EV 812076J VR ROTARY RK09L1140 L12.5 B103
TR201 ET 430868J TR C.DTC114EKA T146T08E
TR202 ET 430868J TR C.DTC114EKA T146T08E
TR203 ET 430868J TR C.DTC114EKA T146T08E
TR204 ET 430868J TR C.DTC114EKA T146T08E
TR205 ET 430868J TR C.DTC114EKA T146T08E
4. FINAL ASSEMBLY BLK
Ref.No. Part.No. Description
1 SA 812668J FOOT B
2 BA L8024A020A PC(#) MAIN BLK E2
3 ZS 394414J BT BID30X08STL BZN
4 ZS 399295 BID30X06STL NI3
5 SB 822025X BUTTON PUSH E
6 SP 822023X PANEL TOP E2
7 ES 812893J SW PUSH SB-221(METAL) 01-01
8 ES 812439J SW120STL CMT
9 ZW 812440J PW122X160X050STL NI3
10 ZW 822022X PW122X180X160STL
11 ZS 822120X 6RB40X060STL BZN
12 SK 822024X KNOB VR
13 AX 822159X AC ADAPTER L8024 J (PLUG IN)
13 AX 822160X AC ADAPTER L8024 C,A (PLUG IN)
13 AX 822161X AC ADAPTER L8024 E,V,B(PLUG IN)
14 EV 812076J VR ROTARY RK09L1140 L12.5 B103
15 EJ 812069J PHONE J HTJ - 064 -13H 6.3
16 EJ 812072J SOCKET DC HTJ-020-05A 1P

SERVICE MANUAL 7
13
FINAL ASSEMBLY BLK
12
11
7
8
9
10
3
3
52
1
4
6
14
16
15
3

SERVICE MANUAL 35
4-7-3, KITA-YAMATA, TSYZUKI-KU, YOKOHAMA, JAPAN
SERVICE SECT. PHONE : [phone] FAX : [phone]

A2File No.123 45678
A B C D E F G H
123 45678 91 0 11
A B C D E F G H
AKAI professional M. I. Corp.
PB1/AN1
1
PB0/AN0
2
AVss
3
TEST
4
X2
5
X1
6
Vss
7
OSC1
8
OSC2
9
RST
10
P90/FVPP
11
P91
12
P92
13
P93
14
P94
15
IRQ0
16
P60 17 P61 18 P62 19 P63 20 P64 21 P65 22 P66 23 P67 24
P50/INT0 25 P51/INT1 26 P52/INT2 27 P53/INT3 28 P54/INT4 29 P55/INT5 30 P56/INT6 31 P57/INT7 32
VCC 33
P73 34
P74/TMRIV 35
P75/TMCIV 36
P76/TMOV 37
P77 38
P80/FTCI 39
P81/FTOA 40
P82/FTOB 41
P83/FTIA 42
P84/FTIB 43
P85/FTIC 44
P86/FTID 45
P87 46
P20/SCK3 47
P21/RXD 48
P22/TXD
49
P32/SO1
50
P31/SI1
51
P30/SCK1
52
P10/TMOW
53
P14/PWM
54
P15/IRQ1
55
P16/IRQ2
56
P17/IRQ3/TRGV
57
AVcc
58
PB7/AN7
59
PB6/AN6
60
PB5/AN5
61
PB4/AN4
62
PB3/AN3
63
PB2/AN2
64
HD64F3644H
IC1
HD6433641RC21H
R2 330
C10 10/16
C11 0.1
TIME
GAP
FBACK DAMP LEVEL RAITO MODE-SW
R4 100K
R5 12K
DSP8 DSP7 DSP6 DSP5 DSP4 DSP3 DSP2 DSP1
TIME
GAP
FBACK
DAMP
LEVEL
RAITO
MODE-SW
ON/OFF
TAP
LED-GND
D+5V
D+5V
D+5V
C6 0.1
1
2
3
4
P4 B4B-PH-K
R7 47K R6
47K
D+5V
C5 10/16
2 3 1
J1 HTJ-020-05A
D1
1N4002
C1 10/16
C2 0.1
Vin
1
GND
2
Vout 3
IC8 NJM78M05DL1A
C3 10/16
C4 0.1
D+5V+9V D+5V
TSTI1
1
OPCL
2
PDAD
3
PDDA
4
PD
5
RST
6
TSTIO1
7
TSTIO2
8
TSTIO3
9
DVB
10
DVB
11
SDIN2
12
SDAD
13
SDOUT2
14
SDDA
15
SDDA2
16
SDOUT3
17
SDOUT1
18
SDIN1
19
SMODE
20
BCLK
21
LRCK
22
CLKO
23
DVDD
24
DVSS
25
XTI 26
XTO 27
TSTI2 28
CS 29
WRQ 30
DVSS 31
IO0 61
DVDD 32
IO1 62
SCLK 33
IO2 63
SI 34
IO3 64
WRDY 35
IO4 65
DRDY 36
IO5 66
SO 37
IO6 67
CASRF 38
IO7 68
RASCE 39
DVSS 69
WE 40
DVDD 70
A16 41
DZFSET 71
A15 42
DVSS 72
A14 43
DVDD 73
A13 44
DVB 74
A12 45
DVB 75
A11 46
DZF2
76
A10 47
DZF1
77
A9 48
NC
78 DVSS 49
AVB
79
DVDD 50
AOUTR2
80
A8 51
AOUTL2
81
A7 52
NC
82
A6 53
AOUTR1
83
A5 54
AOUTL1
84
A4 55
VRDAL
85
A3 56
AVSS
86
A2 57
AVDD
87
A1 58
VRDAH
88
A0 59
NC
89
OE 60
AINR-
90
AINR+
91
AINL-
92
AINL+
93
VCOM
94
VRADL
95
AVSS
96
AVDD
97
VRADH
98
AVB
99
NC
100
DSP
AK7712A-VT
IC2
AK7712A-VT
R8 10K
C18 0.01
X1
16.9344MHz
D+5V
C20 20P C19 20P
C27 0.1
DSP7 DSP6 DSP5 DSP4 DSP3 DSP1 DSP2 CASRF RASCE WE
A+5V
D+5V
C15 0.1
C14 220/10
C16
220/10
C17
0.1
C25 0.1
C12 0.1
C13 10/16
C26 0.1
D+5V
RA8
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
RD0
RD1
RD2
RD3
RD4
RD5
RD6
RD7
OE
DSP8
1 2 3 4 5 6 7 10
11 12 13 14 15
VCC 16
D
Q
CK
CLK
D
QCK
CLK
D
Q
CK
CLK
D Q
CK
CLK
D QCK
CLK
D Q
CK
CLK
8 9
IC4 HD74HC174FP 1
2 3 4 5 6 7 10
11 12 13 14 15
VCC 16
1B 1Y 2B
GND
8 9
2Y 1A 2A
4A 4B 3A 3B G 4Y
3Y
S
IC5 HD74HC157FP
1 2 3 4 5 6
GND
78
9 10 11 12 13
VCC 14
CK PR
Q
Q
D
CLR CK
PR
Q Q
D
CLR
IC6 HD74HC74FP VCC
1
DQ1
2
DQ2
3
DQ3
4
DQ4
5
WE
6
RAS
7
A0
10
A1
11
A2
12
A3
13
VCC
14
DQ8 27
VSS 28
NC
8
A10R
9
VSS 15
A4 16 A5 17 A6 18 A7 19 A8 20 A9 21
OE 22
CAS 23 DQ5 24 DQ6 25 DQ7 26
IC3 MSM5117800D-60J
C28 0.1
D+5V D+5V
C30 0.1
RD7 RD6 RD5 RD4 RA7 RA6 RA5 RA4
RA8
RA4
RA1
RA2
RA3
D+5V
RD0 RD1 RD2 RD3 RA3 RA2 RA1 RA0
C29 0.1
D+5V
2 4 3 1
J301 HTJ-064-13H
2 4 3 1
J306 HTJ-064-13H
2 4 3 1
J305 HTJ-064-13H
2 4 3 1
J304 HTJ-064-13H
2 4 3 1
J303 HTJ-064-13H
2 4 3 1
J302 HTJ-064-13H
TR301 2SK930 D
R301
2.2M
C301 10/16
R302 22K
R303 680K
R304 2.2K
C302 10/16
+9V
R320
1K
R319 1K R318 1K R317 1K
R316 1K
R315 100K
VREF+9V
R308 10K
R309 100K R313 10K R312 10K R311 10K R310 10K
C305 47/16
VREF+9V
R314 10K
C306 100P
C308 10/16
R305
10K
R306 12K
C303 100P
C307 10/16
VREF+9V
+9V
C310 0.01
C309 10/16
C304 10/16
R307 470K
2 3
1
84
IC301A
NJM4558M
76
5
IC301B NJM4558M
C151 10/16
R151 10K
76
5
IC102B NJM2904M
R152 10K
C152 100P
VREF+5V
2 3
1
84
IC102A
NJM2904M
R153 10K
R157 4.7K
VREF+5V
A+5V
C156 0.01
C155 10/16
R154
10K
C153 100P
R155 330
R156 330
R158 4.7K
C154 1500P
3 21
84
IC101A
NJM2904M
R104 100K
R103 100K
7
5 6
IC101B
NJM2904M
R101 100K
R102 100K
+9V
C105
0.01
C104 10/16
+9V
A+5V
C102 10/16C101 10/16
VREF+9V VREF+5V
3 21
84
IC103A NJM4558M
R123 5.6K
C122470P
R122
100K
C124 220P
R121
10K
C121 10/16
VREF+9V
+9V
C116 0.01
C115 10/16
C123
10/16
R124 100K
R113 5.6K
C112470P
R112
100K
C114 220P
R111
10K
C111 10/16
VREF+9V
C113 10/16
R114 100K
7
5 6
IC103B
NJM4558M
3 21
84
IC104A NJM4558M
R143 5.6K
C142470P
R142
100K
C144 220P
R141
10K
C141 10/16
VREF+9V
+9V
C136 0.01
C135 10/16
C143 10/16
R144 100K
R133 5.6K
C132470P
R132
100K
C134 220P
R131
10K
C131 10/16
VREF+9V
C133 10/16
R134 100K
7
5 6
IC104B
NJM4558M
13 54
2
VR201
RK09L1140 103B
13 54
2
VR202
RK09L1140 103B
13 54
2
VR203
RK09L1140 103B
13 54
2
VR204
RK09L1140 103B
13 54
2
VR205
RK09L1140 103B
13 54
2
VR206
RK09L1140 103B
R201 4.7K R202
4.7K R203
4.7K R204
4.7K R205
4.7K R206
4.7K
TIME.
D201
L-934SGD GREEN
D205
L-934SRD-G RED
TR201
DTC114EKA TR205
DTC114EKA
R208 47K
R219 47K
R213 1.5K
R209 680
C205
10/16(MS5)
R218 10K
C201
10/16(MS5)
R214 1K TAPE ECHO/
D+5V.
D+5V.
TIME.
GAP.
FBACK.
DAMP.
LEVEL.
RATIO.
MODE-SW.
LED-ON/OFF.
LED-TAP.
D+5V.
TIME GAP FEED BACK HF DAMP LEVEL RAITO
SW901 SB-285
SW902 SB-285
ON/OFF PLAY/STOP TAP TEMPO
REC/OVER DUB
FOOT SW
GAP.
FBACK.
DAMP.
LEVEL.
RATIO.
LED-TAP.
MODE-SW.
LED-ON/OFF.
C22 0.1
C21 220/10
INPUT HD4 OUT HD3 OUT HD2 OUT HD1 OUT MIX OUT
DC IN 9V UNLESS OTHERWISE SPECIFIED
ALL RESISTORS IN OHMS 1/6W ALL CAPACITORS IN uF,P=PF ALL ERECTROLYIC CAPACITORS IN uF/WV
NOTE:
C103 10/16
C316 1000P C315 1000P C314 1000P C313 1000P C312 2200P
W901 WIRE ASSY L8024(2) PH 4P
R9 12K
JW51
D-GNDA-GND
D202
L-934SGD GREEN
TR202
DTC114EKA
R210 680
C202
10/16(MS5)
R215 1K
D203
L-934SYD YELLOW
TR203
DTC114EKA
R211 1.8K
C203
10/16(MS5)
R216 1K
D204
L-934SRD-G RED
TR204
DTC114EKA
R212 1.5K
C204
10/16(MS5)
R217 1K
SW201
SKHHAM004A (SKHHAMA010)
3
2
1
4 5
SW202 SSSU011700
3
2
1
4 5
SW203 SSSU011700
R207 47K
NORMAL DELAY/
LOOPING REC
LED-REC.
LED-DELAY.
LED-ECHO.
L-LEVEL.
L-TIME.
L-TIME L-LEVEL
TAP
LED-REC
ON/OFF
LED-DELAY
LED-ECHO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
P2 B16-PH-K 16P
LED-REC
LED-DELAY
LED-ECHO
L-LEVEL
L-TIME
LED-REC.
LED-DELAY.
LED-ECHO.
L-LEVEL.
L-TIME.
JW52
A+5V
VCC
2RST 1
GND
3
IC7 DS1811R-10
R145 10K R135 10K
R125 10K
R115 10K
C137 10/16 C147 10/16
C127 10/16
C117 10/16
LED-GND.
C33 0.1
C32 0.1
C31 0.1
C24 0.1
JW53
LED-GND
R220 680 R221
680
10K
TR320 DTC114TKA
10K
TR321
DTC114TKA
10K
TR322
DTC114TKA
R321 22K
47K
47K
TR323 DTA144EKA
TR325 DTC114EKA
TR324
DTC114EKA
D+5V
1
2
3
4
5
6
7
8
W201-1 WIRE ASSY L8024(1) SAN-PH 16P(1)
1
2
3
4
5
6
7
8
W201-2
WIRE ASSY L8024(1) SAN-PH 16P(2)
JW50
JW1
SCHEMATIC DIAGRAM L8024A5010 E2
C34
220/10
R10
4.7K
C23 20P