Underground Radio Propagation

[Yorkie]

Some year ago, a well respected Leeds radio amateur, John Heys, of the White Roe Amateur Radio Club (designer of the White Rose ARS Receiver project), conducted a great deal of research into cave radio and designed transmitters and receivers which featured in RSGB's Radcom. There are some pics here, but no additional info:

http://whiterose.shacknet.nu/cave_radio.html

The British Cave Research Organisation claims to be one of the most advanced outfits of its kind in developing cave communications, and has an extensive website which might be of interest. You'll find the BCRA here:

http://bcra.org.uk/creg/

Hope that helps a bit Lawrence.