I have posted this recommendation from Doug. Although I have purchased one of these cards, I cannot personally vouch for how effective it is, now how it compares to other options, as I haven’t yet had a chance to use it. I know thay Doug has it working very effectively woth his SuperSID in the USA, and it provides him with a wide VLF range going above 24KHz by some considerable distance, so that he can monitor VLF stations up there.
