Motorola Gp328 Gp338 Detailed 6804110j64 F Manual

Troubleshooting charts6C-39IF Signal at
L311?No
RF Signal at
T301?RF Signal at
C310?NoRF Signal at
C307?NoRF Signal at
C301?No orCheck harmonic filters L101 & L102 and
ant. switches CR101, CR102, L104Check filter between
C301 & C307; program
filter to schematic test
freq and check varactor
voltages.Inject RF into J101Are varactor
voltages OK?NoYe sCheck RF amp (Q301)
Stage.Check filter between
C310 & T301.Ye sCheck T301, T302,
CR306, R308, R309,
R310Ye s1st LO O/P
OK?
Locked?Ye sCheck FGUYe sTrace IF...

6C-40Troubleshooting chartsSTARTNo PowerIs There B+
Bias for Ant
switchC h e c k Q 111Is Current
OK?Is Control Volt-
age High or LowCheck PCIC1. Check Pin Diodes
2. Check Harmonic FilterInspect/Repair Tx.
Output NetworkIs Power
OK?DoneCheck Drive to
ModuleIs Drive
OK?Troubleshoot
VCOInspect PA Network/
Check Power Out of
U101 at Cap C160Is Power
OK?Replace U101Is Power
OK?Replace Q101DoneDoneNo
Ye s
Ye sNo
No
Ye sLow
High
No
Ye s
Ye s
No
Ye s
NoTroubleshooting Flow Chart for Transmitter...

Troubleshooting charts6C-415V
at pin 6 of
CR201Is information
frommP U409
correct?Is U201 Pin 18
AT 4.54 VDC?Is U201 Pin 47
AT = 13 VDCIs U241 Pin 19
4.3 VDC in TX?StartVi s u a l
check of the
Board OK?Correct
ProblemCheck 5V
Regulator+5V at U201
Pin’s
13 & 30?Is 16.8MHz
Signal at
U201 Pin 19?Check FL201, C206,
C207, C208, CR203 &
R204Are signals
at Pin’s 14 &
15 of U201?Check
L202Check Q260,
Q261 & R260U201 pin 2 at
>3VinTxand
-30 dBm?Are R231,R232,
R233,C231,C232,
& C233 OK?Replace U201If L261, C263 &...

6C-42Troubleshooting chartsSTARTNo LO?Tx Carrier?VCO OKCheck
R260TRB = 5V?Pin 10
>1V?L253 O/C?Change
L253Change
U241AUX 3
High?Check U201
Pin 2 for 3.2VPin 19
=0VAUX 4
High?Change
Q261Vctrl0V
or 13V?L243 Open
Circuit?Change
U241Change
L243Change
U201Check for faulty parts or dry
joints of L271, L273, C370,
C386, R339 & L320A
ANo
No Ye s
Ye s Ye s
No
NoYe sYe s
Ye s
No
Ye sNoNoYe sYe sNo
NoCheck R245 for dry
joint or faultyNoTroubleshooting Flow Chart for VCO...

6D-1Section 6D
MODEL CHART AND TEST SPECIFICATIONS (330-400
MHZ)1.0 Model ChartGP Series, 330-400 MHzModel DescriptionAZH25PDC9AA3GP328 330-400 MHz 4W 16 CHAZH25PDH9AA6 GP338 330-400 MHz 4W 128 CHItem DescriptionXPMUD1536GP328 Super Tanapa 330-400 MHz 4W
X PMUD1537 GP338 Super Tanapa 330-400 MHz 4WXPMUD1541GP328 Tanapa 330-400 MHz 4W
X PMUD1542 GP338 Tanapa 330-400 MHz 4WXPMLD4136GP328 B/C Kit 330-400 MHz 4W
X PMLD4137 GP338 B/C Kit 330-400 MHz 4WXPMLN4216GP328 Front Housing Kit
X PMLN4199 GP338 Front...

6D-2Specifications2.0 SpecificationsGeneralTransmitter
ReceiverAll specifications are subject to change without notice.330-400MHzFrequency:330-400 MHz
Channel Capacity: GP328 : 16 Channels
GP338 : 128 ChannelsPower Supply:7.5 Volts±20%
Dimensions
with Standard
High Capacity
NiMH Battery:
with Ultra High
Capacity NiMH Bat-
tery:137mm x 57.5mm x
37.5mm
137mm x 57.5mm x
40mmWeight:
with Standard
High Capacity
NiMH Battery:
with Ultra High
Capacity NiMH Bat-
tery:420 g
500 g
Average Battery
Life @ (5-5-90...

Transmitter6D-33.0 Transmitter3.1 General(Refer to Figure 6-1)
The VHF transmitter contains five basic circuits:
1.power amplifier
2.antenna switch
3.harmonic filter
4.antenna matching network
5.power control integrated circuit (PCIC).3.1.1 Power AmplifierThe 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 supplying an output...

6D-4Transmitter3.1.2 Antenna SwitchThe antenna switch circuit consists of two PIN diodes (CR101 and CR102), a pi network (C107, L104
and C106), and two current limiting resistors (R101, R170). In the transmit mode, B+ at PCIC (U102)
pin 23 will go low and turn on Q111 where a B+ bias is applied to the antenna switch circuit to bias the
diodes on. The shunt diode (CR102) shorts out the receiver port, and the pi network, which
operates as a quarter wave transmission line, transforms the low impedance of...

Receiver6D-54.0 Receiver4.1 Receiver Front-End(Refer to330-400MHz Receiver Front End Schematic Diagramon page 6D-16 and330-400MHz
Transmitter Schematic Diagramon page 6D-20)
The RF signal is received by the antenna and applied to a low-pass filter. For VHF, the filter consists
of L101, L102, C102, C103, C104. The filtered RF signal is passed through the antenna switch. The
antenna switch circuit consists of two PIN diodes(CR101 and CR102) and a pi network (C106, L104
and C107).The signal is then applied...

6D-6ReceiverThe output of the post-RF amplifier filter which is connected to the passive double balanced mixer
consists of T301, T302 and CR306. Matching of the filter to the mixer is provided by C381. After
mixing with the first LO signal from the voltage controlled oscillator (VCO) using low side injection, the
RF signal is down-converted to the 45.1 MHz IF signal.
The IF signal coming out of the mixer is transfered to the crystal filter (FL301) through a resistor pad
and a diplexer (C322 and L310)....