Chapter 4, Troubleshooting
Questionable Measurement Results
Questionable Measurement ResultsOverview | Refer to the topics in this section if you are seeing measurement results with no |
| indicated errors, but you are failing a test or you believe you’re getting erroneous |
| results. The following pages list some common sources of measurement errors for |
| each type of test. |
Average Power | Potential causes of measurement error in average power readings include: |
| Cable loss values are incorrect |
| Since the Software will compensate for the cable loss between your base station’s |
| transmitter test port and the Test System, it is very important that you have the |
| correct values entered into the Configuration Information Menu. |
| You can view the loss value in the Average power menu. If they do not match |
| your setup (do not forget to allow for losses through couplers, attenuators, and so |
| forth) go to the Configuration Information Menu and enter the correct |
| value under TX Measurement Path Loss. |
| Power meter not zeroed recently |
| Periodically, you should zero the power meter. This is done by pressing the |
| Zero Pow (k1) key while in the Average power menu. |
| Measurement units are incorrect |
| Verify that the measurement display is reporting in the units that you expect for |
| this test (choices are Watts, milliwatts, and dBm). The displayed units can be |
| changed in the Average power menu using USER keys k2, k3, and k4. |
| Input signal is outside the measurement range of the PCS Interface |
| The specified range for average power measurements with the PCS Interface is |
| −13 to +30 dBm (50 μW to 1 W) when testing CDMA base station transmitters. |
| Verify that the signal applied to the RF IN/OUT port of the PCS Interface falls |
| within this range before continuing with your tests. You can use the Go To |
| Spectrum Analyzer modes to view the transmitted signal. |
| Connections are missing or faulty |
| Make sure that you have connected your transmitter signal to the RF IN/OUT port |
| on the front panel of the PCS Interface. |
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