Nokia Mobile Phones NSE-5 Series Service Manual page 240

NSE–5
Troubleshooting
D
RF control lines:
RxC (R725) 0–>2.3Vmax during receiving slot
AFC (C747) 0– 1.2V typ. during receiving slot
OK?
Yes
Analog data signals:
RxIP & RxIN 0–>1.5V DC during receiving slot
Recieved signal is biased to DC, amplitude
50mVpp nominal and frequency 13MHz
OK?
Yes
RF control lines:
TxC (C700) 0–>2.3Vmax during transmit slot
TxP (R706) 0–>2.8V (logical signal) during
transmit slot
OK?
No
Check N200 if TxC fail
else
Check D300
Check RF part
Page 14
No
Check N200
No
Check N200 if DC fail
or
RF part
Yes
Analog data signals:
TxIN & TxIP (C709) 0–>0.8V DC during transmit slot
TxQN & TxQP (C708) 0–>0.8V DC during transmit slot
Transmit signal is biased to DC, amplitude 300mVpp
and frequency 64kHz
OK?
Yes
PAMS
Technical Documentation
No
Check N200
Figure 11.
Issue 1 07/99