I never said all the mixers were sub-harmonic mixers.
There are a lot of mixers but the bit I was referring to starts from about 8:45 onwards. Of those three mixers labelled as #2, #3 and #4 on the block diagram, I think that only #3 and #4 are the (sub)harmonic type. But your commentary suggests that they are all subharmonic.
Also your commentary from 9:18 indicates that you think that you were pretty certain that mixer #2 (17GHz) was subharmonic.
I think this mixer is fundamental mode only. I think that it is a fundamental mixer when used as the second mixer on the 9kHz-3.6GHz low band range and also when it is used as the first mixer on the 3.6-17.1GHz range. I guess it's no big deal either way and it doesn't really detract from the video...
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