Keysight N5241A/42A/49A Service Guide 3-45Tests and AdjustmentsPerformance Tests— Z5623 Opt H01 dynamic accuracy test set— Signalgenerator— Powermeter— Powersensor— TwotestcablesDescription of the Test:The linearity of the noise receiver is tested over its full dynamic range at a singCW frequency. All three gain stages are tested at 2 dB increments with 8 noiseaverages per point. Since the PNA-X source cannot be on while noise figuremeasurements are made, an external signal source is required.1. The signal generator is connected to the dynamic accuracy test set’ssource port and the dynamic accuracy test set’s receiver port is connectedto the PNA-X Port 2. A power sensor is connected to the dynamicaccuracy test set’s power meter port.2. Within the dynamic accuracy test set, the source signal is routed througha small amplifier and a 10 dB step attenuator, A1, to a power splitter. Oneside of the power splitter is connected to the power sensor port. Thesignal from the other side of the splitter is routed through a 110 dB stepattenuator, A2, to the receiver port.3. The PNA-X is set to make a relative noise power measurement with thenoise gain set to 0 dB.4. With the amplifier active and A1 set to 0 dB, the signal generator power isadjusted to achieve exactly- 10.0 dBm at the power sensor. This is the power meter referencereading, Pmr.5. A2 is set to 50, 60, or 70 dB, depending on the gain stage being tested,and the analyzer’s noise receiver power level is measured. This is theanalyzer reference reading, Par.6. A1 is changed to 2, 4, 6, 8 and 10 dB. At each point, delta power levels areread on the power meter, Pmd and the analyzer, Pad.7. The power linearity error at each point is calculated as Pe = (Pmr – Pmd) –(Par – Pad).8. A2 is incremented 10 dB, A1 is set to 0 dB, and the signal generator’ssource power is adjusted until the receiver power level is exactly the sameas it was before the attenuators were switched.9. New power meter and analyzer receiver reference readings are recorded.The process is repeated until the total attenuation reaches the minimumtest level.10.The process is reset to the reference levels from step 4, and it is run inreverse until the total attenuation reaches the maximum test level.
