22 Keysight NFA X-Series Getting Started and Troubleshooting GuideQuick StartUsing the U7227-Series USB Preamplifiers in Noise Figure MeasurementsInitial Connection to the Signal AnalyzerThe U7227-Series USB Preamplifier is powered via a USB connection from thesignal analyzer. To connect it to the analyzer, follow the steps below.1. Connect the Output port of the USB preamplifier to the RF Input port ofthe signal analyzer.2. Connect the USB port (Type-B) of the USB preamplifier to the USB port(Type-A) of the signal analyzer either in the front panel or in the rear panelusing a USB cable. You can “hot plug” the USB preamplifier into theanalyzer’s USB port at any time.Figure 1-2 shows the U7227-Series USB Preamplifier connection in the twostages of the noise figure measurement. While the USB preamplifier is pluggedinto one of the analyzer’s USB ports, the analyzer will consider it to be in theRF input signal path and will apply the gain settings and other calibration dataof the USB preamplifier to the measurements.Figure 1-2 U7227-Series USB Preamplifier and Analyzer Connection in the Two Stages ofNoise Figure MeasurementBefore connecting a signal to the input port of the U7227-Series USBPreamplifier, make sure the USB preamplifier can safely accept the signallevel provided. The signal level limits are marked next to the Inputconnectors of the USB preamplifier.The USB connections of the U7227-Series USB Preamplifier and thekeyboard to the signal analyzer must be separated from each other; forexample, the USB preamplifier connects through the front panel while thekeyboard connects through the back panel.
