The transmitted frequencies are that low that they can directly be received using a laptop soundcard. This solution comes from the Alexander association, the guys that run and maintain the old Grimeton Station.
Using a short whip receiving the E-field. It is a classical super heteodyne receiver with an IF of about 455 kHz and a BFO. Look for: A very simple VLF Pocket receiver by By Wilfried Fritz, DJ1WF. The Receiver: I checked several web sites to see what other people are doing and I saw 3 solutions:
