Hi Gary,
Thanks for your email. Good to see you stay active receicing on VLF. Let
me answer to the group, maybe some more OMs are interested in the topic.
Regarding local QRM and the antenna choice, i'm afraid a loop could
perform worse, because it receives the H fields coming from inside the
house. But anyway worth a try and you know you can turn the loop to
eliminate QRM if it comes from just one direction.
What do you think about using 2 loops and a stereo soundcard to build a
RDF grabber like DF6NM does on LF and i do on MF? That would be
interesting to follow and it is not much effort to install...
Today i'm also going to build a new preamp for my VLF loop. It should
provide at least 10 dB more gain as the current one and it should have a
wide and flat frequency response. I'm also playing with a RLC network
into the USB DC feed for the soundcard.
Remember the suggestions from M0BMU,
https://77ac4273-a-62cb3a1a-s-sites.googlegroups.com/site/sub9khz/antennas/9khz_loop_preamp_v2.png?attachauth=ANoY7crFVu5byeC0tIYPiVmKhyN6xRQGADHVtykFlY12oqOKXyOiWd3lfxigP5iyCtKPpm7SjRSFReF786xGmu0Ih0AkhpOz4zxGngxDQlSVOpLNUcehxloQu1Ai6rn-aX340qT6lrkA4OndTg5ZnUeN8OIPcBuCF25xIzejy_MYAR0SHm32ReoacmSGn4-EQzXC_AH8v5D93_umnGivTzLiFKkgvm4XuGLPt8gxRh9TaARQV6UbcrQ%3D&attredirects=0
Another idea to build the loop is to use a CAT5 LAN cable, 10m long with
all the wires switched in series. The screen may help a bit too. I tried
that with good success a few years ago...
73, GL and i hope you will see me soon there.
Stefan
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