Roger Lapthorn G3XBM has reported that both the 29.499 kHz Transatlantic transmissions have been heard in the UK
His transmitter has a 3CX3000A7 tube in the final, running grounded grid and generating 800 W. The effective isotropic radiated power (EIRP), however, was estimated to be approximately 1 mW. To operate on 10,000 meters, Raide has a 90 foot vertical antenna using a reconfigured Zepp, fed via a huge loading coil that is 4 feet tall, more than 1 foot across and comprised of some 2000 feet of #14 wire. He employs a few thousand feet of “chicken wire” for his radial system.
The transmission consisted of “XBA” sent at a rate of 120 seconds (2 minutes) per dot and 360 seconds (6 minutes) per dash of CW. In the UK Nicholson copied the signal on software using a PC sound card with a preamplifier ahead of it. His antenna is a pair of orthogonal loops, each 20 meters square, at ground level, transformer coupled to the preamplifier.
Spectrogram of the 29.499 kHz VLF signal - http://abelian.org/vlf/sg29499.shtml
Paul Nicholson VLF website - http://abelian.org/
Roger Lapthorn G3XBM Blog - http://g3xbm-qrp.blogspot.com/