Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual

Troubleshooting charts5B-29
9.0 Troubleshooting charts
MCU Check
Power Up 
Alert Tone
 OK?
Speaker
OK?
U409 EXTAL= 
7.3728 MHz? 
U201 Pin 19 
16.8 MHz
5V at U247?
3.3V at U248?
U409 Reset Pin 
94 High?
MCU is OK
Not able to pro-
gram RF Board 
ICsBefore replacing 
MCU, check SPI 
clock, SPI data, and 
RF IC select 
Replace Speaker
Read Radio OK? 
Check 
Setup
Reprogram the 
correct data. 
See FGU 
Troubleshooting
7.5V at 
Pin 3/5 U247? 4/
3.3V at Pin 1 
U248Check 
Q400
Replace U247/
U248
Check any short...

5B-30Troubleshooting charts
Bad SINAD
Bad 20dB Quieting
No Recovered AudioSTART
Audio at pin 27 
of U301?Check ControllerYe s
No
Spray of inject 1st IF into 
XTAL Filter
IF Freq: 45.1MHz
Audio heard?BYe s
No
Check 2nd LO Control 
Voltage at C363
VCO locked?BYe s
16.8 MHz 
check at pin 22 
U301?
Activity on 
U301 sel pin?
Check FGU
No
No
A
A
Ye sCheck Q320  bias cir-
cuitry for faults.
Rotate Freq. Knob
Check controller.
Before replacing U301, check 2nd VCO 
Q320. Check VCO O/P level, C351, 
C352. 
Ye s...

Troubleshooting charts5B-31
IF Signal at 
L311?
No
RF Signal at 
T301?
RF Signal at 
C310?
No
RF Signal at 
C307?
No
RF Signal at 
C301?
No or 
Check harmonic filters L101 & L102 and ant. 
switches CR101, CR102, L104
Check filter between C301 
& C307; program filter to 
schematic test freq and 
check varactor voltages.
Inject RF into J101
Are varactor 
voltages OK?
No
Ye s
Check RF amp (Q301) 
Stage.
Check filter between 
C310 & T301.
Ye s
Check T301, T302, 
CR306, R308, R309, 
R310
Ye s
1st LO O/P 
OK?...

5B-32Troubleshooting charts
START
No Power
Is There B+ 
Bias for Ant 
switchCheck Q111
Is Current 
OK?Is Control Voltage 
High or LowCheck PCIC
1. Check Pin Diodes
2. Check Harmonic Filter
Inspect/Repair Tx. Out-
put Network
Is Power 
OK?
Done
Check Drive to 
Module
Is Drive  
OK?
Troubleshoot 
VCO
Inspect PA Network/Check 
Power Out of U101 at Cap 
C160
Is Power 
OK?
Replace U101
Is Power 
OK?
Replace Q101
Done
Done
No
Ye s
Ye sNo
No
Ye sLow
High
No
Ye s
Ye s
No
Ye s
No
Troubleshooting Flow Chart for...

Troubleshooting charts5B-33
5V
 at pin 6 of 
CR201
Is information
from µP U409
correct?
Is U201 Pin 18 
AT 4.54 VDC?
Is U201 Pin 47 
AT = 13 VDC
Is U241 Pin 19
4.3 VDC in TX?
Start
Vis u a l 
check of the 
Board OK?Correct
Problem
Check 5V 
Regulator
+5V at U201
Pin’s
13 & 30?
Is 16.8MHz
Signal at
U201 Pin 19?
Check FL201, C206, 
C207, C208, CR203 & 
R204
Are signals
at Pin’s 14 &
15 of U201?
Check 
L202Check Q260, 
Q261 & R260
U201 pin 2 at 
>3V in Tx and 
-30 dBm?
Are R231,R232,
R233,C231,C232,
& C233...

5B-34Troubleshooting charts
START
No LO?
Tx Carrier?
VCO OK
Check 
R260
TRB = 5V?Pin 10 
>1V?
L253 O/C?Change 
L253
Change 
U241
AUX 3 
High?
Check U201 
Pin 2 for 3.2V
Pin 19 =0V
AUX 4 
High?
Change 
Q261
V ctrl 0V 
or 13V?
L243 Open 
Circuit?
Change 
U241
Change 
L243
Change 
U201
Check for faulty parts or dry 
joints of L271, L273, C370, 
C386, R339 & L320 A
A
No
No Ye s
Ye s Ye s
No
NoYe sYe s
Ye s
No
Ye sNoNoYe sYe s
No
No
Check R245 for dry 
joint or faulty
No
Troubleshooting Flow Chart for VCO 

5C-1
Section 5C
MODEL CHART AND TEST SPECIFICATIONS (450-527 
MHZ)
1.0 Model Chart
GP Series, UHF Band 2, 450-527 MHz
ModelDescription
AZH38SDC9AA2GP328 Plus 450-527 MHz 4W 4 CH 
AZH38SDC9AA3GP328 Plus 450-527 MHz 4W 16 CH 
AZH38SDH9AA6GP338 Plus 450-527 MHz 4W 128 CH 
AZH38SDH9DU6GP338 XLS 450-527 MHz 4W 160 CH
ItemDescription
XPMUE2049_GP328 Plus Super Tanapa 450-527 MHz 4W 4CH
XPMUE1701_GP328 Plus Super Tanapa 450-527 MHz 4W 16CH
XPMUE1702_GP338 Plus Super Tanapa 450-527 MHz 4W 128CH
XPMUE1877_GP338...

5C-2Specifications (for GP328 Plus)
2.0 Specifications (for GP328 
Plus)
General
Transmitter
Receiver
All specifications are subject to change without notice.
UHF
Frequency:450-527 MHz
Channel Capacity:GP328 Plus : 4/16 Chan-
nels
Power Supply:7.5 Volts ±20%
Dimensions
   with Standard 
High  Capacity 
 
Lithium Battery:
   with Ultra High 
Capacity Lithium 
Battery:
101.5mm x 55.5mm x 
30.5mm
101.5mm x 55.5mm x 
35.5mm
Weight:
   with Standard 
High Capacity 
 
Lithium Battery:
   with Ultra High...

Specifications (for GP338 Plus/GP338 XLS) 5C-3
3.0 Specifications (for GP338 
Plus/GP338 XLS)
General
Transmitter
Receiver
All specifications are subject to change without notice.
UHF
Frequency:450-527 MHz
Channel Capacity:GP338 Plus 128 Chan-
nels/GP338 XLS 160 
Channels
Power Supply:7.5 Volts ±20%
Dimensions
   with Standard 
High  Capacity 
 
Lithium Battery:
   with Ultra High 
Capacity Lithium 
Battery:
101.5mm x 55.5mm x 
33.0mm
101.5mm x 55.5mm x 
38.0mm
Weight:
   with Standard 
High Capacity...

5C-4Transmitter
4.0Transmitter
4.1 General
(Refer to Figure 5-1)
The  UHF transmitter contains five basic circuits:  
1.Power Amplifier  
2.Antenna Switch
3.Harmonic Filter
4.Antenna Matching Network
5.Power Control Integrated Circuit (PCIC).
4.1.1 Power Amplifier
The power amplifier consists of two devices:
1.9Z67 LDMOS driver IC (U101) and 
2.PRF1507 LDMOS PA (Q110).  
The  9Z67 LDMOS driver IC contains a 2 stage amplification with a supply voltage of 7.3V.  
This RF power amplifier is capable of...