PXIe, 6.6 GHz, PXI RF Signal Downconverter—The NI 5601 helps you convert RF frequencies to a lower level to perform the digitization process. It features a wide real-time bandwidth and a highly stable timebase, accurate to within ±50 ppb. The NI 5601 provides integration with modular digitizers for RF analysis applications. It features an SMA female connector and supports both AC and DC coupling.