CCS Technical Documentation
Troubleshooting Instructions
Company confidential
NPM-6/6X
Issue 2 06/03
Copyright
Nokia. All rights reserved..
Page 11
Figure 5: PA and Antenna Switch troubleshooting
PA & ant switch
troubleshooting
Yes
Check with RF probe
signal level on
PA input >=0dBm (*
OK ?
Yes
Replace
ant. switch
Yes
*(When 1kOhm passive probe is used,
correct the measurement by +26dB
Check with
oscilloscope:
-VANT_1 (GSM900)
-VANT_2 (GSM1800)
-VANT_3 (GSM1900)
OK ?
Check with
oscilloscope:
-VBATT ~4V
- VTXB = 2.8 V pulsed
- VTxLO_GSM = 0V (GSM900)
OK ?
Check
VANT lline components
OK ?
Replace
PA
Replace
HELGA
Replace
faulty
component(s)
Check components
around PA
OK ?
Replace
faulty
component(s)
Yes
Yes
Yes
No
No
No
No
-VANT_1 (EGSM900)
-VANT_2 (GSM1800)
-VANT_3 (GSM1900)
(EGSM900)