User Guide

RH-17
Troubleshooting — RF CCS Technical Documentation
Page 20 Nokia Corporation Confidential Issue 1 04/2003
Test 15 ST Robin VHF PLL CELL
Description
This is one of the phone’s self-tests which gives either a pass or fail result. The VHFPLL is
inside the Robin IC. The phone checks the VHFPLL’s lock detect bit. If this bit indicates
that the PLL is unlocked, the test will fail.
Explanation of Result
Pass or Fail
Manual Verification
Turn on the Cell CDMA transmitter to any channel and probe at C638 (probing point
TP27 in Table 2) using an RF probe connected to a spectrum analyzer tuned to 345.2MHz.
If th PLL is locked, it will be stable in frequency. If it is unlocked, you may have to use a
wide span to see it since it may be far off frequency.
Troubleshooting
First, check that V601 and V602 have the proper orientation, then check C612, C613,
R607, R605, C632, R606, C638, L611, C631, C630, C629, C637, R609, C618, and R613.
Check power supplies to N601 (Robin) and ensure there is 2.7v on VR3 and VR6, and 1.8v
on VIO (Table 13). Next, check if CLK 19M2_R (C513) the reference frequency for PLL is
at 19.2MHz. If no problems are found, replace Robin.
Test 16 ST TX Detector CELL
Description
This is one of the phone’s self-tests which gives either a pass or fail result only. The
phone transmits at several power levels and checks the ADC value of the power detector.
The ADC value is measured first for a set of AGC values, then each AGC value is changed
one at a time to make sure that the ADC changes as each AGC value is changed individ-
ually.
Explanation of Result
Pass or Fail
Manual Verification
Using Main Mode: turn on the Cell CDMA TX with channel set to 384, and turn on IS95
modulation using CDMA control.
Using the PDM window, set:
TX_IF_AGC to -100
TX_RF_AGC to -512
PA_AGC to +511