The National Instruments part number 781431-01 refers to the PXIe-5605 RF Signal Downconverter Module, designed for high-precision RF signal processing. This module features an SMA female connector and supports both AC and DC coupling, ensuring versatile application in various RF environments. Operating over a broad frequency range of 20 Hz to 14 GHz, the 781431-01 excels in automated testing scenarios. It is an essential component of the PXIe-5665 RF Vector Signal Analyzer and interfaces effectively with other modules such as the PXIe-5653 Analog Signal Generator and PXIe-5622 IF Digitizer. The downconverter delivers an impressive average noise level of -165 dBm/Hz at 1 GHz and a phase noise specification of -129 dBc/Hz. It is compatible with NI-RFSA software for auto control of its IF filters, which include three selectable types: 5 MHz, 300 kHz, and a Through filter, the latter offering a nominal bandwidth of 80 MHz at -6 dB. Additionally, enabling the pre-selector allows for a typical bandwidth of 47 MHz. The 5 MHz filter provides a nominal bandwidth at -3 dB and operates at an output IF frequency of 190 MHz, while the 300 kHz filter supports a nominal IF output frequency of 199 MHz at -3 dB. The module includes multiple connectors—one RF IN, one IF OUT, one LO1 IN, one LO2 IN, one LO3 IN, and three LO OUT connectors (LO1 OUT, LO2 OUT, LO3 OUT)—and comes with an external DC block compatible with an SMA DC block to protect the RF IN from DC signals. The PXIe-5605 measures 8.5 inches by 3.2 inches by 5.1 inches and weighs 66.4 ounces, with a recommended calibration interval of two years to maintain optimal performance.