My goal is to be able to supply a CW signal to the DUT and measure the down-converted power out in dBm. Is this possible with an N5224A and SMC? Or would this be a case requiring a signal generator?
If you have the 4-Port, dual source option (option 400), then you don't need an additional source, but if you don't have the dual source, then you will need an external source for the LO. However, in either case, you can use SMC set to CW sweep type to make your measurement. The parameter you are looking for (output power at IF) is called OPwr in the SMC channel.
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