Motorola Mototrbo - Troubleshooting Charts; 1.0 Troubleshooting Flow Chart for Receiver

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Section 1
TROUBLESHOOTING CHARTS
1.0 Troubleshooting Flow Chart for Receiver (Sheet 1 of 3)
No RX AUDIO
Set radio in Analog mode on 155.1
MHz @ 12.5 KHz channel spacing
with open squelch
Inject 155.1 MHz @ RF LEVEL of -47
dBm modulated with 1.5 KHz FM
deviation with 1 KHz audio tone at the
antenna
Using DMM probe at R1065
1.8 V
present?
> 5.0 V
Present?
Refer to the Controller
section
Refer to the VCO Section
Using a DMM, probe E0401
8.8 V
present?
Refer to RFIC section
Using a DMM, probe R0421
and R0404
> 3.0 V
Present?
> 2.0 V
Present?
Check circuitry around
Q0403 and look for opens
and shorts
Using a DMM, probe
E0500
Using a DMM, probe
E0402
Using an oscilloscope
probe at R1059,
R1000, R1002,
R1003, and R1004
Any
Activity?
Yes
Yes
Yes
Yes
Yes
A
Yes
No
No
No
No
No
No