User Guide

RH-20 Company confidential
CCS Technical Documentation
Page 12 Nokia Corporation. Issue 1 10/2003
Figure 5: PA and Antenna Switch troubleshooting
Yes Yes
Yes No
Yes No
Yes
No
Yes
No
PA & Antenna Switch
troubleshooting
Check with RF probe signal level on PA
input ~ -1…+5 dBm
OK?
Check with oscilloscope:
-VANT1 (GSM900)
-VANT2 (GSM1800)
-VANT3 (GSM1900)
OK?
Replace ant.
switch
Check with oscilloscope:
-VBATT ~4V
-VTXB = 2.8V pulsed
-VPCTRL_900/1800/1900
OK?
Check VANT line
components
OK?
Replace PA
Replace
HELGO
Replace faulty
com
p
onent
(
s
)
Check components
around PA
OK?
Replace faulty
com
p
onent
(
s
)