If you're interested in RF circuits, I highly recommend taking a look at X-MWblocks prototyping framework by https://quanticxmw.com/

Really love your work. Used to work for a microwave components (passive and active + measurement) house back in the 70s and 80s, and still miss it.

Have you considered making something more expensive with better performance? Commercially? You mention Keysight VNA's in the $10,000+ range, but we regularly buy VNA's in the $100,000+ range. I imagine with a $1000 budget you could do quite a lot.

Thank you for elaborating on your design & making it public.

Last winter I made a design for a hobby spectrum analyser and the main stumbling block was a suitable low phase noise oscillator. Most of the RF sources that I came about have terrible spurs from pll adjusts when they are used for sweeping. I’ve been thinking about buying a YIG on ebay and do it that way but that approach would devalue the project for open source.

I’m eager to look at that lmx2594 you use, thank you for the article.

Thanks for the submission. Author here if you have any questions.