Nokia NPM-10 Series Troubleshooting Instructions page 28

NPM-10
Troubleshooting Instructions RF
Troubleshooting chart for PCS transmitter
Measure Power Measure
on ANT with TX Power
No
Power Meter on PCS-TX.
or RCT
> 28 dBm Power ~ 28 dBm
Yes
Yes
With Scope check
Check R759, Ant. switch:
L702 Vcon2_DCS = 2.7 V
Vcon1_GSM = 2.7 V
Yes
Check Z700
( Ant. switch )
** TXIQ signals look the same in PCS and GSM
Page 28
Measure Measure
Pout_DCS Pin_PCS
No No
29 dBm -2 dBm
Yes Yes
With Scope
Check L709 check :
( Coupler ) VPCTRL_P
( See figure 21 )
Yes
Check N700
( PA )
With Scope
check :
TXC
( See figure 21 )
Yes
Check V700
( detector )
+
discretes around
Figure 20: GSM1900 transmitter troubleshooting chart
PCS 1900 band, Power level 0, Channel 661
Black trace:Vpctrl_P @ R708 output
Figure 21: VPCTRL_P
Nokia Corporation
CCS Technical Documentation
Measure
Measure BAL
OUT_D_TX
input to T600
No No
Buffer input
-4 dBm
-3 dBm
Yes Yes
With Scope
check : Check T602
VTX_B_P = 2.7 ( PCS Balun)
V
Yes
Check V701
+
NO
discretes around
NO
NO
Confidential
With Scope
check :
No
VTX= 2.7V +
discretes around
Yes
Check TXIP and
TXQP
( See figure 19 )
Yes
Check
NO
Base band
NO
NO
Check Mjolner
+
the serial bus
Issue 1 03/2003