If you are testing a mixer with a single LO and you want to measure IMD, then you do need an additional external source. the 4-port PNA-X can be configured to use the external source either as the LO for the mixer or as the 2nd tone (F2) for the IMD measurement. the most simple configuration is to use the external source as the LO. if you don't have to measure the LO port match, then you simply connect the mixer between ports 1 and 2 of the PNA-X and you connect the external source's RF output directly to the mixer LO port. you will still need to connect the 10 MHz references of the PNA-X and source together and you will need setup the external source as an external device on the PNA-X, so that the PNA-X can control the source and set its power and frequency(ies). If you do need to also measure LO match or any kind of LO to RF or LO to IF isolation, then that setup is also possible, but it is a bit more complicated. let us know if you do have these additional measurement requirements, and we'll be happy to provide a simple block diagram of the measurement setup.
Feb 29, 2016 9:02 AM