Service manual

2-31
March 2000
Part No. 001-3139-502
800 MHz RDM SCHEMATIC
FIGURE 2-11
FOLDOUT
C50
.01
R77
12k
RT85
8k
U17A
3403
+
1
3
2
R76
6.8k
+4.5V
C49
.01
R75
4.7k
U17B
3403
+
7
5
6
R84
500k
R74
2.7k
C48
2200pF
CR14
CR15 CR13
CR12
U17C
3403
+
9
10
8
R79
10k
R83
10k
R80
47k
C46
.1
R78
47k
C47
.1
U17D
3403
+
13
12
14
R82
1M
R81
330k
R116
43k
C66
.1
U10C
4049
76
TP7
C55
.01
R89
12k
RT97
8k
U19A
3403
+
1
3
2
R88
6.8k
C54
.01
R87
4.7k
U19B
3403
+
7
5
6
R96
500k
+4.5
V
R86
2.7k
C53
2200pF
CR18
CR19 CR17
CR16
U19C
3403
+
9
10
8
R91
10k
R95
10k
R92
47k
C51
.1
R90
47k
C52
.1
U19D
3403
+
13
12
14
R94
1M
R93
330k
R117
43k
C67
.1
U10A
4049
32
TP5
C60
.01
R101
12k
RT109
8k
U21A
3403
+
1
3
2
R100
6.8k
C59
.01
R99
4.7k
U21B
3403
+
7
5
6
R108
500k
R98
2.7k
C58
2200pF
CR22
CR23 CR21
CR20
U17C
3403
+
9
10
8
R103
10k
R107
10k
R104
47k
C56
.1
R102
47k
C57
.1
U21D
3403
+
13
12
14
R106
1M
R105
330k
R118
43k
C68
.1
U10B
4049
54
TP6
C15
470pF
C19
1
R28
10k
R29
100k
U6A
3403
+
R30
1k
2
3
1
TP3
U8A
4066
21
13
R31
100k
R39
100k
+9V
R46
100k
C27
1
R47
33k
R45
4.3k
U6D
3403
+
13
12
14
34
5
U8B
4066
R32
100k
C20
1
R34
4.7k
R35
100k
R36
1k
U6D
3403
+
+4.5
V
R38
100k
R37
10k
C21
1
7
6
5
C17
10
R43
300
WO 24
SWITCH TX
AUDIO 2
C22
1
R40
100k
U6C
3403
+
R41
100k
+4.5
V
9
10
8
TP4
WO 59
C16
10
R42
300
WO 23
SWITCH TX
AUDIO 1
U2D
74C906
89 RxA
U2C
74C906
65 FSK
R72
500k
C43
2200pF
R62
2.7k
U16B
3403
+
6
5
7
R63
4.7k
C44
.01
U16A
3403
+
2
3
1
R64
6.8k
RT73
8k
R65
12k
C45
.01
CR1
0
CR1
1
CR8
CR9
R67
10k
R71
10k
U16C
3403
+
R68
47k
C41
.1
R66
47k
C42
.1
9
10
8
U16D
3403
+
13
12
14
R70
1M
R69
330k
+4.5
V
R6
43k
C26
.1
U10D
4049
910
TP8
13
14
15
12
1
2
3
8
11SW Tx
LT R
FSK
RxA
/DTR
PI 0
PI 1
PI 2
PI 7
TxD P3 I
U11A
RS-232
U2F
74C9
06
RxD P3 O
PI 4
10
5
C5
5-35pF
20
Vss
18
XTAL 2
XTAL 1
19
Y1
11.059 MHz
C3
20pF
C4
20pF
R3
100k
U2C
74C906
R4
10k
R5
10k
C1
470pF
+5V
31
7
WO62
1213
152
W56 W63
RS-232 Rx
WO
7
PI 6
EA/V
DD
INT 1
P33
TO P34
TI P35
INT 0
P32
6
U2A
4049
PI 5
21
C2
470pF
R2
100k
+9V
U2E
4049
11 10 4
PI 3
9
RST/V
PD
REPEATER
Rx AUDIO
S3
R11
10k
+5V
2
RES IN
C6
.001
C7
10
1
3
4
REF
CT
GND
U3
7705
+5V
R9
10k
7
8
SENSE
INPUT
VS
5
RESET
RESET
6
R10
8.2k
3
RESET
8
TC
C69
.01
+5V
2
1
Vcc
RING
-5V
4
V
BB
C25
.0022
R44
910
6
7
CAP 1
CAP 2
11
B RTS
9
12
A GND
RTS
U9
7911
10
24
XTAL 2
Y2
2.458
MHz
C24
20pF
C23
20pF
23
22
20
19
17
XTAL 1/
CLK
TD
D GND
MC 3
MC 2
MC 0
+5V
21
18
MC 4
MC 1
16
DTR
U1
8751
+5V
40
Vcc
C70
.01
R120
10k
16 1
15
14
13
12
11
2
3
4
5
6
11 10
12
13
14
15
16
9
8
7
6
5
17
18
4
3
R121
10k
R122
10k
R123
10k
R124
10k
R125
10k
S1
R126
10k
R127
10k
R128
10k
R129
10k
R130
10k
R131
10k
R132
10k
R133
10k
+5V
2
1
19
20
R134
10k
R135
10k
S2
P20 A8
P21 A9
P22 A10
P23 A11
P24 A12
P25 A13
P26 A14
P27 A15
P36 WR
P37 RD
28
27
26
25
24
23
22
21
33
32
16
17
PO 6
AD6
PO 7
AD7
PO 5
AD5
PO 4
AD4
PO 3
AD3
PO 2
AD2
PO 1
AD1
PO 0
AD0
34
35
36
37
38
39
SW Tx
LSB
MSB
R48
47k
R33
10k
R61
220
4
3
5
U7B
4066
2
3
4
R1
220
1
10
J1
+5V
5
7
6
8
11
12
9
/DTR
LT R
+5V
R7
10k
R8
47k
U11B
RS-
232
U7A
4066
12
13
314
WO2
WO1
W57
R12
100k
C8
82pF
C13
.022
R13
100k
R14
47k
C11
.01
U4D
3403
+
+9V
R15
10k
R16
12k
C28
1
13
12
14
R17
56k
R18
56k
C14
.047
U4C
3403
+
C12
.0068
9
10
8
R19
12k
U4B
3403
+
7
6
5
+9V
R21
12k
R22
10k
C18
1
TP1
C10
15
C9
15
CR3
CR4
U4A
3403
+
U6C
3403
+
CR5
1
8
2
3
9
10
R23
47k
R24
100k
R25
100k
U5A
3403
+
R26
2.2k
R27
2.2k
TP2
REPEATER Rx DATA
C37
470pF
F1
2A
W51
POWER
WO21
WO3
WO30
Z1
1
2
3
C38
470pF
+
C74
10
U14
1
2
3
+
C40
10
C71
.01
C72
.01
C73
.01
U15
7805
1
2
3
+
C39
10
+5V+9V
SOURCE SOURCE
W52
R58
10k
R59
10k
+9V
C31
1
U5B
3403
+
6
5
7
C32
1
R60
10k
+4.5V
SOURCE
C34
10
2
4
3
CAP
CAP
GND
U12
ICL7660
+9V
8
Vcc
V OUT
5
CR6
C35
.01
+
C33
10
U13
3201
1
2
3
C36
1
-7.5V -5V
SOURCE SOURCE
Y3
OUTPUT
B
SW
AF
GND
4
1
2
3
5
R115
47
C62
.1
+9V
R114
1k
L1
6.8uH
C61
12pF
C63
.01
R112
33k
R113
56k
Q2
3658
R111
100
C64
.01
R110
220
+9V
C65
.01
WO34
WO35
1
2
3
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
+4.5V
W9
W10
CR2
GRN
W11
W12
CR1
RED
W14 SQUECLH ENABLE TO RECEIVER J101, PIN 14
GND
W13 LOGIC NOISE SQUELCH TO RECEIVER J101, PIN 5
W15 NOISE AMP OUTPUT TO RECEIVER JCT R97/C133
W18 REPEATER RECEIVE AUDIO IN TO RECEIVER J101, PIN 10
W19 REPEATER RECEIVE DATA IN TO RECEIVER J101, PIN 1
W16 +13.8V DC IN TO RECEIVER J101, PIN 12
P1
RECEIVER FRONT PANEL
NOTES:
1. ALL RESISTORS ARE IN OHMS AND CAPACITORS IN MICROFARADS
UNLESS OTHERWISE SPECIFIED.
2. IC PIN NUMBERS NOT SHOWN:
IC
PIN NUMBER
+5V +9V -5V -7.5V
GND
U1
40
20
U2, U7
14
7
U3
8
3
U4, U5, U6, U16, U17, U19, U21
4
11
U8
14
7
U9
2
4
9, 22
U10
1
8
U11
16 8
9