Chimera: 2.
a thing that is hoped or wished for but in fact is illusory or impossible to achieve.
(from the Oxford English Language Dictionary).
Phase Noise. We know what it is, but how do you measure it? Pete N6QW and I went through this back when people were casting phase noise aspersions at (Pete's!) beloved Si5351. More recently phase noise hate has been focused on (my?) beloved Franklin oscillator. When I asked a very technically proficient and guy at the VWS club if he could measure phase noise, I was surprised when he honestly said that he could not.
And now we have the IMSAI guy saying, essentially, the same thing. Wow, if the VWS guy and the IMSAI guy -- with all the spectrum analyzers at their disposal -- have trouble measuring phase noise, what hope do we ordinary hams have? I mean, at best most of us have just an oscilloscope, a NanoVNA, and a TinySA.
Look, I know that phase noise is real and in certain circumstances, it is important. But sometimes I suspect that its measurement is also a bit of a technical chimera: If, for whatever reason, there is a circuit that you don't like, you can claim that the phase noise of that circuit is bad. Or horrible. I think we see this sometimes with the Franklin oscillator. Very few hams will be able to measure it and dispute the assertion that the phase noise is bad.
For a perhaps painful walk down SoldeSmoke's "Phase Noise Memory Lane" go here:
Thanks to the IMSAI guy for a great video. But let me ask: Is there a better, simpler way to measure phase noise? One that will avoid chimerical results and that could be used by hams with sort of standard ('scope, sig gen, NanoVNA, TinySA) test gear?
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