Series 8650A Universal Power Meters - Giga-tronics

2Adjustments & Performance Tests2.1 IntroductionThis chapter defines procedures for adjustments and performance testing for the Series 8650A UniversalPower Meters.2.2 Calibration ProcedureIf any of the instrument performance characteristics cannot be calibrated within specification, refer tothe Troubleshooting Chapter of the 8650A Service Manual.2.2.1 Equipment RequirementsTable 2-1 lists the equipment required for calibration of the 8650A power meters.Table 2-1: Related Equipment ListDescription Representative Model Key CharacteristicsCW Thermistor Power Meter HP 432A VRF and Vcomp available externallyThermistor Mount HP 478-H75< 1.07 VSWR @ 50 MHz(30 dB return loss)Accuracy + 0.5% @ 50 MHzDigital Voltmeter HP 34401A +0.05% accuracy & 1 µV resolutionPCWin 95, 98, 2000, NTPC comm port software HyperTerminal TM Serial Port Communications software9 pin Type D Serial Cable Radio Shack P/N 26-117 Serial cable (non-null modem)2.2.2 Calibrator Output PowerPower up the 8650A and allow for a 30 minute warm up period. Perform the Calibrator Performanceand Output Power Reference Level tests (see section 2.3). The unit should meet all requiredperformance specifications. If the unit fails to meet the 1 mW Reference Output Specification withinthe 0.981 mW to 1.019 mW minimum and maximum limits, continue to section 2.2.3.2.2.3 1 mW Reference Output AdjustmentConnect the test equipment per Figure 2-1. Set the 50 MHz calibrator to 0 dBm from the front panel ofthe 8650A and turn on the calibrator. Using the HyperTerminal TM program, connect to the 8650A andenter the command “XC TESTCAL”. Record the 50 MHz Cal Factor from the response into the CalFactor column of the Calibrator Cal Factor table. Type “T” and press “Enter”. Enter “0” at the prompt toreset the calibrator cal factor to zero. Measure the calibrator output using the following procedure:Manual 32089, Rev. A, December 2000 2-1