I remember some of the members suddenly perked up a bit and a lively discussion of the build and use of the VNA, that cost me maybe £10 to build ($15) started up, especially involving those that used big professional bits of kit with huge price tags. I also went on to show the N2PK VNA kit I had planned on using but was missing a few bits and I ended up ordering 4 sets of components for club members to build their own.
Obviously everyone knows the MiniVNA from IW3HEV now from WiMo etc but this was his first design.
With hindsight showed I was totally niave about amateur radio although I knew what I wanted to show in the talk so built the VNA and the TCVR and spare modules with no thought as to the apparent magnitide of what I had done.
Anyway, I won the club award for a talk that year hihi.
But I KNEW I'd seen the design and use somewhere else before.