VHF (136-174 MHz)
Troubleshooting Flow Chart
24
6. Troubleshooting Flow Chart
6.1
Control Circuit
Check the control
circuit
The product powers on
normally?[1]
Check U304, U306,
U303 and control circuit.
LED works normally?
3V3D is normal?
Replace LED
Check U2013,
U309
Reset
Check U305
Yes
No
Yes
No
Yes
Yes
No
No
Yes
No
No
19.2MHz crystal
oscillator is normal?[3]
The control circuit
is normal.
The RF circuit is
normal?[2]
Yes
No
Completed
Yes
1V3D is normal?
Check the power-on
circuit and U2014
1V8D is normal?
Description of Normal Situations:
Summary of Contents for PD502
Page 1: ...PORTABLE...
Page 5: ...VHF 136 174 MHz...
Page 13: ...VHF 136 174 MHz Exploded View and Packaging Guide 7 3 2 Packaging Guide...
Page 18: ...VHF 136 174 MHz Circuit Description 12...
Page 43: ...PCB 3 9 PCB VHF 136 174 MHz...
Page 44: ...PCB 3 VHF 136 174 MHz...
Page 71: ...UHF1 400 470 MHz...
Page 79: ...UHF1 400 470MHz Exploded View and Packaging Guide 7 3 2 Packaging Guide...
Page 84: ...UHF1 400 470MHz Circuit Description 12...
Page 108: ...UHF1 400 470MHz PCB 36 9 PCB...
Page 109: ...UHF1 400 470MHz PCB 37...
Page 136: ...1616300000260 2014 03 17 L07157 4...