Motorola Gm328 Gm338 Gm398 Detailed 6804112j18 E Manual

Troubleshooting Flow Chart for 40W Transmitter 3-3
2.0 Troubleshooting Flow Chart for 40W Transmitter (Sheet 1 of 2)
Control Volt-
age at  
TP4533
>1V Current 
increase 
when 
keyed?NO YES
START
Check if Pressure Pad closes S5440
Check Components between 
Q4441 and RF Output, 
Antenna Switch 
D4471,D4472,Q4472, 
VR4471,Q4471>500mA & 6A
4V 
DCReplace PCIC U4501
NO
YESTP4530 
9.1V DC
If U4201 Pin 2 is high,  
replace PCIC 
U4501,otherwise 
check controller and 
FGU
YES
NOTP4531 
>0.5V DC?Replace PCIC...

3-4 Troubleshooting Flow Chart for 40W Transmitter
2.1Troubleshooting Flow Chart for 40W Transmitter (Sheet 2 of 2)
Check PA Stages
YES Check 
MOSBIAS_2/
MOSBIAS_3
YES
Are D4471 & 
D4472 OK?
Check 
ASFIC
NO
YES
Check Q4421 
gate (12kohm) 
and drain resis-
tances (15kohm)
NOChange 
Q4421
Is drive from 
VCO 
>+4dBm?Do visual check on 
all components
YES
Is voltage drop 
across R4497 
>4.5V?
NO
1
Check 
PCIC_MOS
BIAS_1Check 
PCIC
Change 
D4471 & 
D4472
Check Q4441 
gate (63kohm) 
and drain resis-
tances...

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

3-6Troubleshooting Flow Chart for VCO
4.0 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...

4-1
Section 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...

4-2Allocation of Schematics and Circuit Boards
THIS PAGE INTENTIONALLY LEFT BLANK 

UHF 25-40W PCB / Schematics / Parts List
4-3
2.0 UHF 25-40W PCB / Schematics / Parts List
C0108C0211
C0212 C0251
C0252
R0103R0211
R0212
R0251 R0252
R0253 R0257
16
1
8
9 U0251
C0253C0256
C0261
C0262R0256
R0268
R0269 8 7114
U0211
C0421
C0441
C0442C0443
C0445
C0446C0447
Q0110
R0222 R0261 R0262R0442
C0104 C0106C0224
C0226
C0227C0228
C0232
C0233
C0236 C0237C0495 R0101R0102
R0104 R0108R0110
R0115
R0116R0226R0227
R0228C0221C0222 C0225
C0241 C0243 R0220R0221
R0223R0224
R0229R0254
R0255
C0235C0242
C0244...

4-4UHF 25-40W PCB / Schematics / Parts List
4 32
Y3101
C3122
C3123
D3101
Q3102 R3113
R3114R3115R3116 R3133
C3116 R3118
C3121
L3112R3112C3104
C3110 C 3 111
C3112
C3113 L 3 111Q3101 R3102
R3104
R3105
R3107 R3108 C3144 C3146
C3147
C3151C3152
Q3141
Q3151Q3152
R3134R3141 R3146
R3147
R3151 R3152
R3153 R3154
4
3
2 FL3111
FL3113
43
2 FL3115C4261C4262
C4263D4261
R4261 TP4201TP4202
4 3
1Y4261 2
34Y4262
6
C4235
R4263L4231C4201C4202C4203
C4204
C4205
C4206 C4207
C4208 C4209
C4211
C4228
C4241
C4287 C4288D4201R4201...

UHF 25-40W PCB / Schematics / Parts List4-5
PASUPVLTG_UHF_PA_1 PASUPVLTGPASUPVLTG
9V3
9V3_UHF_PA_1C4602
.033uF
3000pF C4481
C4485
30pFL4402
30pF C4484
.033uF C4421
1000pF C4495
NU NUC4490
1000pF C4497 C4489
BLM31A02PTL4474L4541NUC4493
1000pF C4478
C4436
10uF
NU0.1uF C4438
17nH L4437L4421
C4423
100pF C4422NU
100pFC4439 L4438
17nHC4437 L4436
NU
NU 13pF C4442C4466 30pF
C4441 6.8pFC4443C4491
3.3pF
C4476
NU
NU C4445
6.8pF
3.3pF C4487
13pF C4444
C4467 C4440
30pFC4477
100K R4409
9V3L4490
12.77nH 12.77nHL4489
NU...

4-6UHF 25-40W PCB / Schematics / Parts List
NU
0 VDC (RX)
NU NU
3.43 VDC
3.05 VDC (RX)NU
4.97 VDC
2.48 VDC
NU
NU4.58 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)
VDC4.97 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...