Solution
The PXIe-5841 is a VST with 1 GHz of instantaneous bandwidth. It combines vector signal generator, vector signal analyzer and high-speed serial interface capabilities with FPGA-based real-time signal processing and control. Given its versatility and functionality, the device features several ports at its front panel. Some of these ports use SMA connectors, but others use MMPX to ensure the best signal stability.
Even though some of the instrument's ports are MMPX, it is possible to connect MMCX cables to these MMPX ports. NI designed the instrument in a way that those MMPX ports are mechanically compatible with MMCX cables, so it is safe to use them from a mechanical point of view.
However, while MMCX cables are compatible, they are fundamentally different from MMPX from an electrical point of view. Therefore, using MMCX cables can degrade the performance of the instrument. For example, MMPX cables have more frequency bandwidth than MMXC ones, which might affect fast-transient signals like triggers. Any user using MMCX cables instead of MMPX ones needs to test the instrument's performance first and ensure the specifications of interest are still valid for their application.