So I was thinking theoretically run a little neon ne2 bulb via one of those 5v - 170v nixie tube dc-dc buck converters and then had a hall effect sensor wired to an esp32 with an LLM inbetween you might have a pretty handy tricorder device to read your body's own natural EM fields given you create a big enough dataset
For academic purposes only of course
What do you think?

There have been a number of tricorder projects and none of them got anywhere. I once tried to make a pip boy like device capable of making local maps based on an ultrasonic sensor. It wasn't easy and I gave up. A true tricorder has to do a lot of things that aren't easy.