Boss Dr. Rhytm DR-550 MK II Service Notes page 7

APRIL.1992
DR-550mk2
CIRCUIT
DIAGRAM/
Wm
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> A
<h <b
ice
UPD74HCU04G
LCD (36)
(33)
(1)
(32)
GUIDE
K»
PAD 12
|
PAD
11
I
PAD
10
I
PAD 9
i-o On A-O
On i-O
0-1
A-O
ACCENT
K>
STOP/CQNT
|
START
A-O
COM3
I
COMO
IC1
CPU
UP075316
BIAS
VLCO
VLCI
VLC2
D3-D17
:
DAN202K T-96
+5V
(DIGITAL)
+5V
(ANALOG)
+9V
(ANALOG)
DIGITAL
GND
ANALOG
GND
BUCK UP
+5V
t
+5Va
t
+9V
t
i
zt
-
a
(@u|
XT2
Y^.
(NC)
m
26 58
m
—
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n
40
&
JK2
IC2
MB076O4PF-G-BND
17
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24
1
4 31
6 30
a 2
6
3
a 29
11
28
7 4
22
25
lo 23
21
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26
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^
27
9
^
5
12
^
6
13
2
7
14
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B
15
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9
19
^
10
IB 11
16
^
12
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31 B
,
12
1
21
32 7
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20
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4 IB
35 B
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17
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37
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24
25
3
4
5
6
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9
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19
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16
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13
12
11
22
27
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CB
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(1/2)
MAIN BOARD
(2/2)
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M
-
TAPE
WE
PHONES
7