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I am going to make a 7th order Chebyshev band stop filter with cut-off frequencies at 9MHz and 11 MHz in order to measure the fundamental tones at 10MHz (with a cheapo OCXO) and at 11MHz with a Rigol DG1022Z.
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There are various ways to do this stuff, but in your case, I'd recommend a different approach.
If I assume you want to do IMD measurements at the 10.7MHz IF of a VHF FM receiver, then it would be wise to do this within the 250kHz bandwidth of a typical 10.7MHz ceramic filter.
One way to do this is with the setup below. The 10.7MHz SSB filter will only be a few kHz wide, and the idea would be to tune the LO (or the test tones) to centre 2f1-f2, f1, f2 and 2f2-f1 at 10.7MHz in turn and then you can compute the TOI.
The setup below would be immune to analyser phase noise effects and also analyser IMD limitations assuming the tone spacing was set at (say) 50kHz.