Motorola Gm Series Detailed 6864115b62 A Manual

Troubleshooting Flow Chart for Synthesizer3-7
4.0 Troubleshooting Flow Chart for Synthesizer
5V
 at pin 6 of 
D4201
Is
information
from
 mP U0101
correct
?
Is
U4201 Pin 47
at = 13VDC
?
Is
U4301 Pin 19
4.5 VDC in TX?  
(at VCO section)
?
Start
Visual 
check of the 
Board
OK?Correct
Problem
Check 5V
Regulator
U4211
+5V
at U4201
Pin’s
13 & 30
?
Is
16.8MHz
Signal at U4201 
Pin 19
?
Check
Y4261 / Y4262 and 
associated Parts
Are
signals
at Pin’s 14 &15 
of U4201
?
Check 
R4201Check C4381
Is
U4201
Pin 2  >4.5...

3-8TROUBLESHOOTING CHARTS
5.0 Troubleshooting Flow Chart for VCO
Are Q4332
Base at 0.7V 
Collector at 4.5V 
Emitter at 110mV
Are Q4301
Base at 2.4V 
Collector at 4.5V 
Emitter at 1.7VAre U4301 Pins
13 at 4.4V
15 at 1.1V
10 at 4.5V
16 at 1.9V
Low or no RF Signal
at TP4003
Visual check
of board
OK?
35mV DC at
U4301 Pin 19
NO
YES
Replace Q4301
at base of Q4332
NO
NO
NO
NO YES
YES
YESYESLow or no RF Signal
at input to PA
4.8V DC at
U4301 Pin 19
Is RF available 
at C4402
YES
YESYES YES NO
NO
NO
NO
NO
Audio...

Chapter 4
UHF PCB/SCHEMATICS/PARTS LISTS
1.0 Allocation of Schematics and Circuit Boards
1.1 Controller Circuits
The UHF circuits are contained on the printed circuit board (PCB) which also contains the Controller 
circuits. This Chapter shows the schematics for the UHF circuits only, refer to the Controller section 
for details of the related Controller circuits . The PCB component layouts and the Parts Lists in this 
Chapter show both the Controller and UHF circuit components. The UHF schematics and...

4-2UHF PCB/Schematics/parts lists
Table 4-3   UHF 1-25W Diagrams and Parts Lists
PCB :
8485670z03 Main Board Top Side
8485670z03 Main Board Bottom SidePage 4-23
Page 4-24
SCHEMATICS
Power Amplifier 1 - 25W
FRACN
Voltage Controlled Oscillator
Receiver Front End
IF
Page 4-25
Page 4-26
Page 4-27
Page 4-28
Page 4-29
Parts List
8485670z03Page 4-30
Controller version is T9 

UHF 1-25W Band1 PCB 8485670z02 / Schematics4-32.0 UHF 1-25W Band1 PCB 8485670z02 / Schematics
TOP METAL
NOISE_BLNKR_CNTLR_1,if_sig4
C0101C0102C0104 C0106
C0107
C0131 C0132C0211
C0212
C0221
C0222
C0223 C0224C0225
C0226
C0227
C0228 C0231
C0232
C0233
C0234C0235 C0236C0237
C0241
C0242 C0243
C0244
C0245C0246 C0251
C0252
C0253C0256
C0261
C0262
C0421
C0441
C0442
C0443
C0445
C0446
C0447
C0448
C0449
C0470
C0471
C0472
C0473
C0474
C0476
C0477
C0478 C0482 C0483
C0484 C0486C0487
C0488
C0490
C0493
C0494
C0495
C0496...

4-4UHF 1-25W Band1 PCB 8485670z02 / Schematics
C0103 C0105
C0111 C0112C0121
C0122 C0123
C0141
C0151
C0201C0202C0203
C0204 C0205
C0254C0255
C0265
C0266C0267
C0271C0272
C0273C0274
C0275
C0276
C0277
C0301
C0302
C0303C0304
C0305 C0324C0325
C0331
C0341
C0342
C0343
C0344
C0351
C0352
C0353C0354 C0422C0423
C0426
C0427
C0428
C0429
C0430
C0431 C0485C0491 C0492
C0497
C0499C0541C0554 C0558C0559
C0560C0575
C0576 C0591
C0592
C0593
C0611
C0621C0622
C0641
C0644C0645
C0661 C0662
C0663
C0671 C3104
C3110 C3111
C3112
C3113...

UHF 1-25W Band1 PCB 8485670z02 / Schematics4-5
NU NU
NU
NUNU
width 2.032
0.8x25 1.542x42.216x__J4401 - BNC
7.5
NU
A
NU
NU
RXIN 9V3
NUNU
INT_SWB_UHF_PA_1L4437
17nH
8.2pF
R4475
10K
C4441
15
100 R4402
2.7R4432
R44272.7 R4425
R4501
6.8K 2200pF C4427 C4424
15pFC4453
100pF
39K R4443 MOSBIAS_222pF C4431
C4506
2200pF 100pF C4406
36pF C4472
1uF C4505 C4413
NU
C4434 C4455
13pF
0.1uF10K R4454
FECTRL_2_UHF_PA_1 2.7K R4452
R4421
27K L4402
57R01
0.1uF C4425
20K R4507 C4423
1uF
LM50
GND
3 1
POSVOUT2FECTRL_2
U4502...

4-6UHF 1-25W Band1 PCB 8485670z02 / Schematics
NU
0 VDC (RX)
NU NU
3.43 VDC
3.05 VDC (RX)
NU
4.97 VDC
2.48 VDC
NU
NU
4.58 VDC 3.79 VDC
2.48 VDC 4.97 VDC (25KHZ Chan. Spacing)
1.78 VDC (Rx)
4.97 VDC (TX) 5 VDC (Locked)10.87 VDC
1.28 VDC
NUNU
NU
0 VDC (Unlocked)
2.63 VDC (TX)
VDC 4.97 VDC
NU
0 VDC (12.5KHZ Chan. Spacing)
2.52 VDC 2.5 to 11 VDC
1.76 VDC (Tx)30mV - 80mV RMS 12.7 VDC
0 VDC 4.97 VDC
NU1.8pF
(SOURCE)
NU
3.48  6.68 VDC
TP4201C4204
100pF
R4204
472.2uF C4214 INPUT8
OUTPUT 1
SENSE 2
SHUTDOWN3...

UHF 1-25W Band1 PCB 8485670z02 / Schematics4-7
NU NU
NU
0 VDC (Tx)
NUNU
NU
NU
2.5 - 11 VDC0 VDC (Rx)
4.58 VDC 4.58 VDC
NUNU
13.5 to 16 dBm 
NU
0 VDC (Tx)
3.1 VDC (Rx)0 VDC (Tx)
4.7 VDC (Rx)
NU
(Tx)
4.54 VDC
0 VDC (Tx)2.35 VDC 
NU
0 VDC (Rx)4.42 VDC (Rx)
NUNU
NUNU
NUNU
NUNU
NUNU
NUNUNU
NU NUNU
4.97 VDC (Tx)-18 to -16 dBm (Rx)
-16 to -11 dBm (Tx) 4 to 6 dBm 4.54 VDC
4.54 VDC (Tx)
2.6 VDC (Tx)1.91 VDC (Tx)
0 VDC (Rx) 2.45 VDC (Rx)(Rx)2.43 VDC (Rx)
NU
NU
GND C4301
100pF
30 R4313 C4372
VCTRL_UHF_VCOL4331
33nH...

4-8UHF 1-25W Band1 PCB 8485670z02 / Schematics
R4066C4069
R4070
.01uF
C4068
100pF
C4065390
C4064
0.1uF
0
100pF390
R4064R4062
1.5K
R4063R4072
10KR4071
10K
C4062
0.1uF R4061
10K
C4061
330pF
R4069
1KR4068
C4066 1.5K
C4067
3300pF
R4054
R4055 R4053
R4052
0 C4060 R4060
330K
L4008
470nH R4022
L40060
R4020C4051
15nH10pF
L4054C4031
13pF
15nH L4053
27nH
C4055
6.2pF
NUC4054
16pFC4053R4051
16pFC405251
L4051
82pF150nHL4005
L4001L4002L4004 C4010
1.8pF 330pF
C4029
C4027C4030
1.8pF
1.8pF
1.8pF C4026
R4013R4015
270...