HP 83236B S Interface manual Questionable Measurement Results, Average Power

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Chapter 4, Troubleshooting

Questionable Measurement Results

Questionable Measurement Results

Overview	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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Contents CDMA/PCS Base Station Test Software, User’s Guide Restricted Operating Overview Conventions Used in this Book Contents Making Measurements Receiver Sensitivity Operating Overview Setting the Test System Beep Glossary Index Getting Started Introduction You must supply Required EquipmentSynth REF Load and Run the CDMA/PCS BS Test Software Tests Main Menu screen CDMA/PCS Test Software main menu features Select Configuration Information Menu Configure the SoftwareScroll to and select your band of interest User k1 Perform Cdma Tests ProblemsIf You Had Perform Cdma Tests Making Measurements Making Measurements Transmitter Measurements Receiver Measurements Other OverviewOverview Average PowerRequirements Information Menu under TX Measurement Path Loss StepsModulation Quality Rho Measurement not Correlating in , Troubleshooting, on Code Domain Power Menu Code Domain Timing Details on the use of the Code Domain Analyzer screen Code Domain Phase Already selected Analyzer Transmit SpectrumSteps Go to Spectrum Analyzer @ Present Chan Steps Go to Spectrum Analyzer & Enter Freq Transmit Spectrum Receiver Sensitivity Main menu, enter the Base Station Channel number Receiver Performance in Additive Noise Error Rate FER is measured at each Eb/No levelEb/No Level Search for PN Offset PN Offset not Found Check Even-Second Clock Check for a valid clock signal from the base stationCorrelating in , Troubleshooting, on Check Even-Second Clock Operating Overview Information ConfigurationReference To select a new PCS Band Selecting a PCS BandChannel plans for PCS Band selections You must know the following loss values Compensating for TX and RX Measurement Path LossBeep Saving Configuration Information to MemoryRequirements Steps Loading Configuration Information from MemoryPurging Configuration Information from Memory Autostart Feature Using AutostartTurning On Turning OffConnections Viewing Instrument ConnectionsSetting the Test System Beep To Memory on Cdma Base Station Operating Overview Troubleshooting Troubleshooting Memory Overflow Errors Errors When Loading and Running the SoftwareTest System Configuration Errors at Runtime Compensation not performed. Check Duplex OUT cable. Retry? Errors When Loading and Running the Software Cdma Measurement not Correlating Errors While Attempting MeasurementsErrors While Attempting Measurements Incorrect Base Station Channel entry Frame Error Rate Receiver MeasurementsErrors While Attempting Measurements Questionable Measurement Results Average PowerCode Domain Rho MeasurementsMeasurements Receiver TestsSensitivity tests random data not selected for signal source Questionable Measurement Results Glossary Glossary Modulation Quality See Rho Glossary Glossary Glossary Index Index FER Index Oqpsk PCS Qpsk UCT Walsh chip