(800/900Mhz, Open Architecture, No Receive Audio) - Motorola Handie-Talkie MTX Series Theory/Troubleshooting Manual

YES
Check Continuity Check
DC Voltage
from Q701
Q701
Collector to U701
Pin C2 Collector
Check
YES
Check DC Voltage
U702 Pin F5
Replace
Q701
Check
YES
DC Voltage
Replace
U702
U702
Pins B5,
C5
Go to DC
Chart 3B
TROUBLESHOOTING FLOW CHART #6B

(800/900MHz, Open Architecture, No Receive Audio)

Check
NO
Replace
R761, C709,
& C792
Check
NO NO
DC Voltage
U701 Pin C2
NO
YES
Replace
U701
NO
Check NO
Replace
C723, R804,
& C805
NO
NO
Replace
U702
Check Continuity
NO
from U702,
Pin C1 to
U701 Pin B4
No/Low Audio
Inject on Freq.
-47dBm Modulated
Carrier
Check
NO
Check U3
Audio J301
and
Pins 10 & 12
U3 Circuitry
YES
Check
NO Replace
Audio J704
Jumper Flex
Pins 10 & 12
YES
Check Check
Audio Audio
U701 Pin J7 U601 Pin E4
YES
YES
Check Check
Audio Audio
U701 Pin J4 U601 Pin F4
YES
YES
Check
Audio
U701 Pin H6
Check
YES
Audio
U702 Pin C6
Check
YES
Audio
U601 Pin C1
Check
Audio
U702 Pins A3,
YES
A5, B2
YES
YES Check
Audio
U701 Pin J5
Check
DC Voltage
U702 Pin C1
YES
Check
Replace
Speaker,
Speaker Flex
HearClear
Radios Only
Check
NO
Replace
C607
Check
NO NO
DC Voltage
U601 Pin B3
and C4
YES
Replace U601
NO
Check
Replace
C605
Check
NO
Replace
C618, U701
Check
NO
Replace
C608, U601
Check Continuity
from U601 Pin B3
to U712 Pins 5, 6,
7, and 8
MAEPF-23446-O
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