5-12
Troubleshooting
YES
NO
YES
NO
NO
Set
• Phone : Test mode
700 CH, 2 level (TCH)
700 CH, -60 dBm (BCCH)
• Spectrum analyzer as shown in Remarks.
• Oscilloscope as shown in Remarks.
Check for:
• U204 soldering.
• U204 pin 4 (DC 2.85V + - 5%).
• U204 pin 3 (DC 1.4V + - 0.1V).
Replace U204 if defective.
Check for:
• U202 pin soldering.
• Ulysse-Nausica.
• S/W.
Check for:
• U206 soldering.
• U206 pin 5,25, 28 (DC 2.85V).
Replace U206 if defective.
YES
NO
Check for:
• U206 soldering.
• U206 pin 5, 25, 28 (DC 2.85V).
Replace U206 if defective.
Check VC-TCXO
U204 pin 3 13MHz oscillation:
Frequency = 13.00 MHz?
Power -15 dBm?
=
>
Check
RF Mainchip
U202 pin 5, 6, 7, 8:
I/Q signal DC 1.35V & 0.5Vp-p?
=
>
Check RF VCO
U206 pin 26, 27:
Freuency = 766 MHz?
Power -26 dBm?
=
>
Check RF 2 VCO
U206 pin 23, 24:
Frequency = 1364.8 MHz?
Power -26 dBm?
=
>
START
Go to B
Remarks
1. Spectrum analyzer : SPAN = 1MHz
VBW = 1MHz
RBW = 3MHz
Press the trace button of spectrum
analyzer on checking test point and
press the max hold of spectrum analyzer.
2. Oscilloscope : 500mV/div, 2ms/div
5.11 TX Power Trouble (DCS)
Summary of Contents for BD20
Page 1: ...GSM PHONE SERVICE MANUAL MODEL BD20 1st version 2004 01 27 ...
Page 2: ...Rev 1 00 ...
Page 36: ...6 PCB Diagram 6 1 Main PCB 6 1 Top View ...
Page 37: ...6 2 PCB Diagram Bottom View ...
Page 46: ...9 Block Diagram 9 1 BB Block Diagram 9 1 ...
Page 48: ...Block Diagram 9 3 Power Supply Block Diagram 9 3 ...
Page 49: ...10 Schematic Diagram 10 1 Key Pad 10 1 ...
Page 50: ...10 2 Schematic Diagram 10 2 Main Board 10 2 1 Chipset ...
Page 51: ...10 3 Schematic Diagram 10 2 2 Memory Melody ...
Page 53: ...10 5 Schematic Diagram 10 2 4 Connector ...
Page 54: ...10 6 Schematic Diagram 10 3 RF Top Schematic 10 3 1 RF Pam ...
