Hytera MD652, Service Manual

Page: 139 / 207

VHF1 (136
‐
174 MHz)
Troubleshooting Flow Chart
31
No Power Output
Power supply is
normal?
Check power supply
circuit
Check U7002
Refer to the
troubleshooting flow
chart of VCO
Check Q7014
and peripheral
components
Control voltage is
normal?[2]
Current is
normal?[1]
TX VCO is normal?[3]
Q7014 power is
normal?[4]
Q7012 power is
normal?[5]
No
Yes
Low
High
No
Yes
Yes
Yes
No
No
Q7010 power is
normal?[6]
Check Q7012
and peripheral
components
Yes
Yes
Check Q7010
and peripheral
components
Q7013 power is
normal?[7]
Yes
Check Q7013 and
peripheral components
Completed
No
No
No
Description of Normal Situations:
[1] In analog mode, the current is about 4.5 A under 25 W power supply and about 0.8 A under 1 W. In
digital mode, the current is about 2.1 A under 25 W power supply and about 0.6 A under 1 W.
Check large PA match
network, antenna switch,
low-pass network, etc.