Voltage Diagrams; Front Unit - Icom IC-703 Service Manual

SECTION 11

VOLTAGE DIAGRAMS

11-1 FRONT UNIT

D14
DAP222 RSK
R8 18k
PRAK
(MENU)
W4
P.AMP
/ATT R2 470
(F-1)
S1
LS22BB-2SD-PG-T
PRED
D15
DAP222
(F-2)
Q18
XP4111
(F-3)
S2
LS22BB-2SD-PG-T ATTD
R9 10k
(TUNER)
(DISP)
D16
R3 470
DAP222 TUND
Q15
(LOCK)
DTA114EE
R99
150 (MODE)
PIT
/SUB SUBD
R7
S13
1k
(TS)
LS22BB-2SD-PG-T
Q12
XP4111
(UP)
DS2
CL-170PG-CD-D
R5 RITD
150
(RX) (DN)
DS1 CL-170UR-CD-D
(LOCK)
DS3 CL-170UR-CD-D
(TX)
Q1
DTC114EE
C33 0.0047
R30 1k
D5
MA2S111
D6
MA2S111
TX: 4.2V
RX: 0.25V
J1
Q4
2SK3065
W2
J7
J8
to Microphone
J5
5V
MAIN
GND
DIAL
EX-2500 DISPLAY BOARD
RSK
PRAK
R20 10k
S3 SKQHFC
R10
R123 390
18k
MENK
R124 390
S4 SKQHFC
R11 R21
R125 390
10k
10k
R126 390
S5 SKQHFC
R127 390 R12
18k
F2K
R128 390
S6 SKQHFC
R13 R22
R129 390
10k 10k
R130 390
KEYLIGHT HIGH: 4.3V: 5.0V: 5.0V
S7 SKQHFC LOW: 3.1V: 5.0V: 0.0V
Q13
OFF: 0.0V: 0.0V: 0.0V
R131 1.2k R14
2SB1132
18k
DISK
R132 1.2k
S8 SKQHFC
R15 R23 D12
R133 1.2k
10k 10k MA2S111
Q14
R134 1.2k 2SC4081
S9 SKQHFC
R16
R135 1.2k
18k
MODK
R136 1.2k
S10 SKQHFC
R24
R137 1.2k R17
Q3
10k 10k D11
2SC4081
R112
DAN222
R138 1.2k 2.7k
S11 SKQHFC
R18
18k
BUPK
R140 820
S12 SKQHFC
R19 R25
R141 820
10k 10k
BACKLIGHT HIGH: 5.0V: 5.0V: 4.1V
LOW : 5.0V: 0.0V: 3.6V
OFF : 0.0V: 0.0V: 0.0V
8VLM
R4 1k
LCKD AF
MIC
R6 1k
TXD MICEL
RXD
L1
100
MIC
MICEL
AF
LBCS 1
P10/TMOW
8VLM KL1S 2
P11/TMOFL
KL2S 3
P12/TMOFH
5V PHNK 4
P13/TMIG
PTTL RSK 5
P14/IRQ4/ADTRG
MDAK 6
R44
P15/IRQ1/TMIC
MDBK 7
3.3k
P16/IRQ2
SDAK 8
P17/IRQ3/TMIF
9
X1
R47
10
47k X2
FUDL 11
VSS
12
OCS2
D7
13
DAP222 R50 1M OSC1
14
TEST
15
RES
R49
PRED 16
1k P20/SCK1
PTTS ATTD 17
P21/SI1
TUND 18
P22/SO1
X1
IC4 RITD 19
P23
CR-567
S-80945CLMC-G7F LCKD 20
(9.8304MHz) P24
1 5 RXD 21
OUT CD P25
2 TXD 22
VDD P26
3 4 PTTS 23
VSS NC P27
BL1S 24
P30/PWM
BL2S 25
P31/UD
R65 R66 R67 R68
10k 10k 10k 10k
SUBD
MDBK
MDAK
5V
11 - 1
5V
Q50 RX: 5.0V
2SB1132
D13 D50
Q51
DAN222 DAN222 AFGL R26
2SC4081
SQLL R27
SFTL R29
D51
MA2S111 SDAK
SDBK
5V
Q2
2SB1132
LEDBRIGHT HIGH: 4.3V: 5.0V
CP31
LOW : 2.8V: 0.0V
R33
D10
2.2
MA2S111
CP32
R143 1M
TXD
8VLM
AF
MIC
MICEL
C43 0.1
C44 2.2
75 SEG27 DCOM8
P90/SEG33
74 SEG26 DSEG101
P87/SEG32
73 SEG25 DSEG100
P86/SEG31
72 SEG24 DSEG99
P85/SEG30
71 SEG22 DSEG98
P84/SEG29
70 SEG21 DSEG97
P83/SEG28
69 SEG20 DSEG96
P82/SEG27
68 SEG19 DSEG95
P81/SEG26
67 SEG17 DSEG94
P80/SEG25
66 SEG15 DSEG93
P77/SEG24
65 SEG16 DSEG92
P76/SEG23
64 SEG14 DSEG91
P75/SEG22
63 SEG13 DSEG90
IC6
P74/SEG21
HD6433842RB27H 62 SEG12 DSEG89
P73/SEG20
61 SEG11 DSEG88
P72/SEG19
60 SEG7 DSEG87
P71/SEG18
59 SEG10 DSEG86
P70/SEG17
58 SEG9 DSEG85
P67/SEG16
57 SEG8 DSEG84
P66/SEG15
56 SEG6 DSEG83
P65/SEG14
55 SEG5 DSEG82
P64/SEG13
54 SEG4 DSEG81
P63/SEG12
53 SEG3 DSEG80
P62/SEG11
52 SEG2 DSEG79
P61/SEG10
51 SEG1 DSEG78
P60/SEG9
EP6
5V
R1 RV-300
5V
SQL
(AF)
GND
5V
AFV
(RF/SQL)
GND
DN
5V
(RIT)
UP
5V
SFT
(SHIFT)
GND
R2 TP96D231E20
5V
4.7k
4.7k
4.7k
R101 100k R102 220k
IC3
TC7W32FU
1 8
2 7
R105 R106
100k 220k
3 6
R38
4 5
100
R104 1M
R37 22k
5V
Q16
CPH3404
8VLM
AF L2
MIC
MICE
L3
HF50ACC322513-B
1 75
COM7 R/W(WR)
2 74
SEG68 E(RD)
3 73
SEG67 CL(OSC2)
4 72
SEG66 CS(OSC1)
5 71
SEG65 AO
6 70
SEG64 SEG0
7 69
SEG63 SEG1
8 68
SEG62 SEG2
9 67
SEG61 SEG3
10 66
SEG60 SEG4
11 65
SEG59 SEG5
12 64
SEG58 SEG6
13 63
IC2
SEG57 SEG7
14 SED1522FOC 62
SEG56 SEG8
15 61
SEG55 SEG9
16 60
SEG54 SEG10
17 59
SEG53 SEG11
18 58
SEG52 SEG12
19 57
SEG51 SEG13
20 56
SEG50 SEG14
21 55
SEG49 SEG15
22 54
SEG48 SEG16
23 53
SEG47 SEG17
24 52
SEG46 SEG18
25 51
SEG45 SEG19
5V
J1
VR BOARD JACK BOARD
LRXD
AFL GND
AF LTXD
MIC
AFS 8V
MICE
AFO
PWRK
L4
HF50ACC322513-B
C28
2.2
C42
0.0047
L30
HF50ACC-
453215P-T
PHONES
AFS
PHNK
J2
AFLS
GND
L31
HF50ACC-
453215P-T
C34
470p
5V
HF50ACC322513-B AFO
MIC
MICE
EP2
d
b
c
WR a
RD
R76 2.2M
AO
CP11
SEG33
SEG34 Q11
2SB1143
SEG35
SEG36
SEG37 CP12
SEG38
SEG39
SEG40 Q10
CP13
2SC4081
SEG41
SEG42
RX: 5.0V
DSEG43
D9
DSEG44
MA2S111
DSEG45
DSEG46
DSEG47
DSEG48
DSEG49
DSEG50
DSEG51
DSEG52
RX: 7.2V RX: 4.9V
IC5
S-812C50AUA-C3E
I O
G
5V