Hytera PD502, Service Manual, Page: 102 / 136

UHF1(400-470MHz) Troubleshooting Flow Chart
30
6.4
FGU
Q 106
、
Q 110
输出是否正常？
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
Yes
No
Yes
No
No
No
No
Completed
Yes
No
No
Yes
FGU check
Check the power supply
circuit..
5V_FGU, 3V3A_RF and
3V3D_RF are normal?
VCO oscillator?
CV is normal?[3]
Q8007 is normal?[5]
Replace Q8007.
Check Q8007 and
peripheral components.
Q8002/Q8003 are
normal?[1]
Replace Q8002 and
Q8003.
Q8004/Q8008 are
normal?[2]
Check Q8004, Q8008
and peripheral
components.
Replace Q8004
and Q8008.
Replace L8018 and
L8045.
L8018 and L8045
are normal?[4]
Feedback is
output?
Check the feedback
circuit.
19.2MHz crystal
oscillates?
Check the 19.2MHz
circuit.
Sky 72310 clock is
normal?[6]
Check the data circuit
of the control circuit.