The derating is always a good thing to note, I was just wondering how stable the resistance has been.

Is this much of a concern for this circuit with the carbon resistive button pads? I feel like those would wear out much quicker?

This is a super late reply to this but is it a varactor tuned hybrid coupler?

I've only seen this type of design once so it could very well be a wrong guess.

me but with the chirp-z transform

Oh damn I jumped the gun, yeah different dielectrics and geometries will do that.

Are they on the same reel? We had a project at work where custom order SMD inductors would have really good variance but only across one manufacturing run. Otherwise, worse than 20% tolerance even at just 10MHz

I love how you wired up the SMA connector

awesome stuff

genuinely curious how you stumbled upon this

I am kinda late to this but is it not a simplified form of a difference equation? Seeing the use of current and previous states along with @tomverbeure.bsky.social's plots which seem to show exponential growth and decay remind me of one. Might try and take a closer look tomorrow. Very cool stuff