Referring to the Fraser-Smith discovery, the May, 1996 issue of Scientific American featured an article called Detecting Natural Electromagnetic Waves which describes how the amateur scientist can make their own antenna to detect these earthquake precursors. The article on page 98 stresses that this is an inexpensive undertaking:
Rebar, an iron rod obtainable at any construction supply house, is inexpensive and makes a suitable core. ...
Some shops that repair electric motors will wind your coil for about $80. Alternatively, you can wind it yourself in an afternoon ...
you will need bell reducers, which are fittings that link pipes of different diameters. ..
Drill half-inch-diameter holes into two plastic coffee cans lids. ..
Use the tines of a dinner fork to guide the wire into snug coils. ..
Encase each completed coil inside a plastic pipe to protect it from the elements. ..
If you have an analog-to- digital interface, you can read the data directly into your home computer.