Experiments with Varactor VFO Tuning

(Took me a long time to post this, sorry. I wrote it in 2023 summer I think. Posted today Feb 17, 2024) I’ve been experimenting with several homebrew thermatron VFO designs lately.  Typically, my VFO design is for a single band, single conversion receiver to mix with the incoming RF and cover 250 to 350…