LF and VLF transmission is interesting because of the numerous technical challenges. Antenna sizes are limited by property size and by statute. Digital transmission rates are also small.
I have collected a number of papers on LF and VLF and have put together two annotated bibliographies: one on general LF and VLF techniques and the other on LF and VLF antennas.
For further information on long wave phenomena, see the Longwave Club of America .
I like to attend Dayton on occasion with my nerd buddy Bob. Chronologically, here are my Dayton Hamvention pix: