Phone Register Failure - Nokia NSE–3 SERIES Service Manual

PAMS
Technical Documentation

Phone register failure

Analog supply voltage VCOBBA is >2.7 V
Supply voltage VCP (N100 pin 32) > 4.8 V
Supply voltage VRX (N100 pin 9) > 2.7 V
Supply voltage VSYN_1 (N100 pin 15) > 2.7 V
Supply voltage VSYN_2 (N100 pin 4) > 2.7 V
Supply voltage VTX (N100 pins 11, 20) > 2.7 V
Synthesizer lines: SEna (N620 pin 56),
RF control lines: RxC (N250 pin 18) 0 –> 2.3 Vmax during receiving slot
Analog data signal RxIP (N250 pin 22) 0–> 1.5 V DC during receiving slot
Analog data signal RxIN (N250 pin 22) 0–> 1.5 V DC during receiving slot
Used benefit signal is biased to DC and its amplitude is 50 mVpp
DAX signal (N250 pin 48) pulses 1 –> 0 during receiving slot
RF control lines: TxC (N250 pin 17) 0 –> 2.3 Vmax during transmit slot
Analog data signals: TxIN (N250 pin 13) 0–> 0.8 V DC during transmit slot
Used benefit signal is biased to DC and its amplitude is 300 mVpp
Original, 11/97
Disassembly & Troubleshooting Instructions
Phone doesn't register to the network
or
phone doesn,t make a call
YES
at pin 7,12 ... of Cobba (N250)
YES
Analog reference voltage Vref is 1.5 V
at pin 9 of Cobba (N250)
YES
during the receiving slot
during the transmitting slot
YES
SClk (N620 pin 54)
SData (N620 pin 55)
pulses 0 –> 1 during receiving slot
YES
AFC (N250 pin 19) 0 – 1.2 V typ. during receiving slot
YES
nominal and frequency is 13 MHz
YES
YES
TxP (D200 pin 176) 0–>1 (2.8 V) during transmit slot
YES
TxIP (N250 pin 14) 0 –>0.8 V DC during transmit slot
TxQN (N250 pin 15) 0 –>0.8 V DC during transmit slot
TxQP (N250 pin 16) 0 –>0.8 V DC during transmit slot
nominal and frequency is 64 kHz
Check
NO
N100
Check
NO
R270, R271
Check
NO
N100, D200
NO
Check
D200
NO
Check
N250
NO
N250 if DC is failed
RF part if benefit signal is failed
NO
Check
N250
N250 if TxC is failed
NO
D200 if TxP is failed
NO
Check
N250
Check
YES
RF part
NSE–3
Check
Check
Check
Check
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