VLF upconverter

Some years ago I needed a VLF upconverter so I could listen for SAQ on 17.2kHz CW. The converter(s) here might be of use to help you copy some of the commercial VLF stations. It will not help copy most amateur VLF stations where frequency accuracy and long integration times are needed.

If my memory serves me right, this design of mine appeared in GQRP SPRAT, although I cannot remember which one it was.

See https://sites.google.com/site/g3xbmqrp3/vlf/vlfconv