CIRCUIT DESCRIPTION
6-27
October 1999
Part No. 001-2009-201
Figure 6-11 BLOCK DIAGRAM
DC
IN
R
T
10
1,
R
T
1
0
2
L
107
U102
T
103
T
104
Q1
08
Q101
T
105
RA
M
P
FB
PF
C
I SE
NSE
L
ADDE
R
R
E
SI
ST
O
R
U1
08
VDC
U109
VC
C
T
106
PW
M OUT
Q1
15,
Q1
1
6
Q1
17,
Q1
1
8
T
106
L
101
SYNC
+
26.
5V DC
EX
T
I
N
T
101
AC
IN
CR10
1
, CR1
02
CR1
10,
C
R
1
1
1
AC
SE
NSE
Q105,
Q1
06
Q103
U1
10
C
Q1
14
T
O
R
E
M
O
TE
EN
ON/OFF SE
NSE
BA
T
T
BA
CK
-U
P
U
115
SHUT
DOWN
U1
05
+
5
V
T
O
U104
U1
06
U101
U1
10
A
Q1
20,
Q12
1
U1
10D
FA
N
T
E
MP OUT
U1
04A/
B
Q1
10,
Q1
1
1
, Q1
12
+
15V DC
U1
12
Q1
2
7
Q1
2
8
CT
VR
E
F
RA
MP
/I
S
D
OUT
Q1
22,
Q12
3
Q1
24,
Q12
5
T
108
L
102
U
116
, Q
1
2
6
U1
19
+
15V DC
OUT
RA
MP
/I
S
D
OUT
+
5
V DC
OUT
U
117
, Q
1
3
3
U120
L
104
T
109
Q1
29,
Q13
0
Q1
31,
Q13
2
U1
13
CT
E
A
OUT
/INV
U1
14
VC
C
OUT
U
118
, Q
1
3
8
U122
-5V DC
OUT
IAC
Q1
07
C
U
R
R
E
N
T
MODE
B
OOST
C
ONVE
R
T
E
R
CU
RR
E
N
T
S
E
N
S
E
VOL
T
AGE
S
E
NSE
Q1
04
U10
7
L
E
V
E
L S
H
IF
TI
N
G
GA
T
E
DR
IVE
2
-TR
A
N
S
IS
TO
R
FWD C
ONVE
R
T
E
R
TH
E
R
M
A
L
ISOL
A
T
ION
HI
/L
O VOL
T
A
GE
U
111
+
15V
+2
6
.5
V
B
U
C
K
C
ONVE
R
T
E
R
C
ONT
R
O
L
L
E
R
SA
WT
OOT
H B
U
F
F
E
R
L1
0
3
OVE
R
VOL
T
AGE
OVE
R
VOL
T
AGE
UNDE
R
VOL
T
AGE
B
U
C
K
C
ONVE
R
T
E
R
B
U
C
K
B
OOST
C
ONVE
R
T
E
R
C
ONT
R
O
L
L
E
R
F
AN C
ONT
R
O
L
L
E
R
AMP
SE
NSOR
TE
M
P
+
5
V
R
E
GUL
A
T
OR
+5
V
R
E
G
+
6
to
+
18V
B
R
IDGE
R
E
C
T
IFIE
R
P
R
O
T
EC
TI
O
N
P
R
O
T
EC
TI
O
N
P
R
O
T
EC
TI
O
N
SHUT
DOWN
OVE
R
VOL
T
A
GE
BU
F
F
E
R
/
HYST
E
R
E
SIS
Summary of Contents for VX 900 MHz LTR
Page 2: ...1 2 October 1995 Part No 001 2008 202...
Page 4: ...1 4 October 1995 Part No 001 2008 202...
Page 24: ...INTRODUCTION AND OPERATION 1 10 October 1999 Part No 001 2009 201...
Page 26: ...INTRODUCTION AND OPERATION 1 12 October 1999 Part No 001 2009 201...
Page 40: ...INSTALLATION 2 14 October 1999 Part No 001 2009 201...
Page 56: ...PULL DOWN MENUS 4 12 October 1999 Part No 001 2009 201...
Page 60: ...REPEATER PROGRAMMING 5 4 October 1999 Part No 001 2009 201...
Page 142: ...SERVICING 8 8 October 1999 Part No 001 2009 201...