User's Manual

Troubleshooting: RFDS

68P64115A18–1

Mar 2003

1X SC 4812T Lite BTS Optimization/ATP Software Release R2.16.1.x

DRAFT

6-26

Troubleshooting: RFDS

Introduction

The RFDS is used to perform Pre–Calibration Verification and

Post-Calibration Audits which limit-check the RFDS-generate and

reported receive levels of every path from the RFDS through the

directional coupler coupled paths. In the event of test failure, refer to the

following tables.

All Tests Fail

Table 6-29: RFDS Fault Isolation – All Tests Fail

Step Action

1 Check the TX calibration equipment for proper operation by manually setting the signal generator

output attenuator to the lowest output power setting and connecting the output port to the spectrum

analyzer RF input port.

2 Set the signal generator output attenuator to –90 dBm, and switch on the RF output. Verify that the

spectrum analyzer can receive the signal, indicate the correct signal strength, (accounting for the cable

insertion loss), and the approximate frequency.

3 Visually inspect RF cabling. Make sure each directional coupler forward and reflected port connects to

the RFDS antenna select unit on the RFDS.

4 Check the wiring against the site documentation wiring diagram or the SC4812ET Lite Installation;

68P09253A36.

5 Verify any changes to the RFDS parameter settings have been downloaded.

6 Status the TSU to verify the TSIC and SUA software versions are correct.

7 Check to see that all RFDS boards show green on the front panel LED indicators. Visually check for

external damage.

8 If any board LEDs do not show green, replace the RFDS with a known–good unit. Re–test after

replacement.