RF Mixer spurious analyser.

With this tool, the output frequencies of an RF mixer are calculated using the Henderson [see the Watkins Johnson application note written by Henderson available after the installation of WinRFCalc] model for spurious calculations. The results are presented in a Spectrum format which is easy to understand.

By moving the RF and LO frequency slider controls, you can immediately see the effect of the changing frequencies on the mixer results, wanted and unwanted. The number above the spectral line is the order of the mixing result.

RF and LO harmonics levels can be set, the green area is the Intermediate Frequency band.

The numbers above the spectral responses are the orders of the spurs. In the graph, you can see that the primary USB and LSB response have a conversion number of two, derived from RF and LO 1st order tone.

At present one mixing stage is available, future versions will be extended with more stages to simulate cascaded multiple superheterodyne designs.