I basically set my vna to the frequency of interest in CW mode (not sweeping) at the lowest power setting, then calibrate to the end of my test cable then attach the can using an sma soldered directly to the legs. I remove the slug, note the reading, then peak the slug and note that reading. That tells me the Xl range and Q so I know what to expect when using it in other circuits.
Why was I doing that? Because dss56 has some stubborn crystals coming my way and I planned on using a SSB tuning coil from a DX2547 (L22) to try to pull it down the necessary amount if pulling it up don't work out.
To that end, I was just playing with simsmith. I was thinking, if I measure the crystal parameters, I could model it ahead of time and see about what it would take to move it to where I want it. Right now, for fun, I am using the crystal frequency and parameters listed in W2AEW's video #319 at timestamp 14:48 to see what a trim cap or inductor would do his crystal in the software. More importantly, I wanted to know if that model lines up with the 47pF trim freq shown in the G3UUR method from earlier in that same video. The answer is yes, and I'm kinda excited about that.
My next step is to measure the parameters of a crystal that I have and see if I can accurately predict the shift from an inductor. For a long time, I wanted to know how they choose those inductor values at the SSB oscillators, and now I think I know.
With a few measurements ahead of time, it may be possible to know exactly what it takes to put the crystal where you want it and that is something i want to be able to accurately ballpark without guessing. #stilllearning for sure!
