Hi Christoph,
Yes I need the (remote) preamp nearly all the time to get sufficient s/n over-ride not helped by feeder length of <200m.. Multi-joined RG6 most over 30 years old with loss about 4dB at 1.8MHz, loop R=10 ohms..
At VLF I find its conventional loop mode better and I did manage to hear the SAQ Xmas transmission on 17.2kHz.. Not as good as other larger antennas because of a 20kHz HPF.
A K9AY does not work as well at VLF. Modelling my loop gives a very low -69.5dBi at 300kHz, and only 5dB better if conventional earth used. Worse at 100kHz. Others may comment on what size (conventional?) loops are best for reception down on VLF frequencies and what sensitivities are needed, I would imagine it has been discussed on this forum before!
73
John
