How do I make spectrum analysis measurements on signals above 50 GHz using a PSA Series Spectrum Analyzer (E4440A, E4446A, E4448A)?

The PSA offers an option (AYZ) enabling the use of external harmonic mixers. The option adds connections to the local oscillator and IF input. The 11970 and 11974 Series mixers are connected to the LO and IF. A harmonic of the LO mixes with the incoming RF signal to produce an IF signal. When the IF signal is 321.4 MHz a response is displayed on the spectrum analyzer.

The 11974 Series preselected harmonic mixers also uses the preslector tune voltage from the rear panel of the PSA. The 11970 series has a frequency range of 18 GHz to 110 GHz and the 11974 series has a frequency range of 26.5 GHz to 75 GHz.