User Guide

PAMS
Technical Documentation
WinTesla User Guide
NHD–4
Page 59
Original 11/97
3. Set the TXB PDM to 128 decimal. This will provide minimum bias to the
CLY–10 (V113).
4. Read the total current draw of the phone. The phone should draw
between 380 and 480 mA, generally about 430 mA. Record this current
value as the CDMA Mode Quiescent Current.
5. Initiate the CDMA Troubleshooting Mode from the Test menu of the
Service Software.
6. Using the PDM controls Adjust the TX_OFFSET PDM until the output
bandpower is –8 dBm.
7. Again use the CDMA TX Manual Gain controls located in the CDMA
tests selection of the Test menu.
8. Use this control to achieve approximately 10 dBm of CDMA TX output
bandpower.
9. From the PDM controls, adjust the TXB PDM until the total current draw
of the phone is 100 mA greater than the CDMA Mode Quiescent Current,
determined in step 4. Accomplishing this, verifies Low CDMA TX Power
Bias.
10. Repeat steps 3 – 5, but for 23 dBm of CDMA TX output bandpower,
and 250 mA of current over the CDMA Mode Quiescent Current,
determined in step 4. Accomplishing this verifies Max CDMA TX Power
Bias.
Troubleshooting
A failure of this test could be attributed to a number of things. Foremost,
both the transmitter and the synthesizer have to be functional. The TXB
PDM is adjusted throughout this tuning, as is the TX Offset PDM. Ensure
their operation. The negative voltage generator N200 and the VTXS
supply should also be inspected for proper operation. If these tunings is
unable to achieve the minimum amount of bias currents there may be a
faulty, misplaced or wrong value component in the bias circuitry
supporting the CLY–10.
TX Gain Limiting Tuning Functionality Test
Manual Test
The CDMA TX Gain Limiting functionality can be verified by performing
the TX Gain Limiting tuning procedure found in the tuning menu of the
Service Software. Another option is to perform the steps below:
1. Initiate the CDMA TX Manual Gain controls from the CDMA Test menu
located in the Service Software.
2. Set the CDMA TX Gain to maximum.
3. From the PDM controls, adjust the TXI_REF PDM to 127 decimal. The
phone should achieve approximately 27 dBm of CDMA output bandpower.