After a bit of head scratching I see the top plate is not connected and is supposed to reflect the energy downward. That doesn't look right to me, but pretty sure most people would say the same about me.
If you go to post 25 (by J_Player) down at the bottom of the post and read the second article on Tesla, this is what Konstantine Meyl is doing. He wrote his papers on this in 1990 but he used pancake coils instead of the long tube coil. Then at the bottom of that article are more links about capacitive antennas. I've mentioned this that the skeptics are misapplying theory when they argue against the frequency discriminators. Beaty discusses this, although not the discriminators.