Hello, I was lucky enough to obtain a Harrison 302 theremin,the one with flat plate antennas, on ebay quite cheaply and once set up I found I couldn't really play it like it was,ie with the flat plates.So I changed the antennas for small stainless steel bowls with the pitch antenna having a small aerial on top.I took a short video of me playing it with the new setup and I show the pitch field which is much more playable now.The addition of the aerial on the bowl for the pitch antenna kind of warped the field(for better linearity) so it's more like the traditional theremin setup.
https://www.youtube.com/watch?v=q2TMOXwRMz8