Motorola Gm328 Gm338 Gm398 Detailed 6804112j18 E Manual

Troubleshooting Flow Chart for VCO3-7
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...

3-8Troubleshooting Flow Chart for VCO
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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
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UHF 1-25W PCBs / Schematics / Parts Lists4-32.0 UHF 1-25W PCBs / Schematics / Parts Lists
TOP METAL
C0101C0102 C0104
C0106
C0107
C0131
C0132 C0211
C0212
C0221
C0222
C0223
C0224
C0225
C0226
C0227
C0228
C0231
C0232
C0233
C0234C0235
C0236C0237
C0241
C0242
C0243
C0244C0245 C0246
C0251
C0252
C0253
C0256
C0261
C0262
C0421
C0441
C0442
C0443
C0445
C0446
C0447
C0448
C0449 C0470
C0471
C0472
C0473
C0474
C0476
C0477
C0478
C0482 C0483
C0484
C0486
C0487
C0488
C0490
C0493
C0494
C0495 C0496
C0501
C0502 C0503 C0504 C0505...

4-4UHF 1-25W PCBs / Schematics / Parts Lists
C0103
C0105
C0111
C0112 C0121
C0122
C0123
C0141
C0151
C0201C0202C0203
C0204
C0205
C0254 C0255
C0265
C0266 C0267
C0271C0272
C0273 C0274
C0275
C0276
C0277
C0301
C0302
C0303 C0304
C0305
C0324
C0325
C0331
C0341
C0342
C0343
C0344
C0351
C0352
C0353C0354
C0422
C0423
C0426
C0427
C0428
C0429
C0430 C0431
C0485 C0491
C0492
C0497
C0499 C0541C0554
C0558
C0559
C0560 C0575
C0576
C0591
C0592
C0593
C0611
C0621C0622
C0641
C0644C0645
C0661
C0662
C0663
C0671
C3104
C3110
C3111...

UHF 1-25W PCBs / Schematics / Parts Lists4-5
ZWG0130520-B
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...

4-6UHF 1-25W PCBs / Schematics / Parts Lists
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...

UHF 1-25W PCBs / Schematics / Parts Lists4-7
NU NU
NU0 VDC (Tx)
NUNU
NU
NU
2.5 - 11 VDC0 VDC (Rx)
4.58 VDC 4.58 VDC
NUNU13.5 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 PCBs / Schematics / Parts Lists
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 C4016...