I recently reproduced a design by PA3GZK that is also described by PI4NOV. Has anyone else built one of these?
The copper for the loop and fittings is fairly expensive and its partially SMD, so be prepared for tiny soldering on small boards. I had to add a SMD low pass filter to the preamp input to suppress FM broadcast images, there aren't any close by AM transmitters so that wasn't a problem but I suspect close by transmitters would be. My finished copy about 5 meters above ground works so well across the LW/MW/HF band it's just shocking, it consistently out performs a 115' long wire and a wideband vertical by a wide margin.
Wasn't really easy and it took a while, but it was oh so worth it.
PA3GZK design:
https://pa0fri.home.xs4all.nl/Ant/Active%20antenna/Active%20receiving%20%20loop%20antenna%20eng.htmPI4NOV (in Dutch):
http://arjan-broekhuizen.wixsite.com/pi4nov/loop-antenne-voor-ontvangstLow Pass Filter:
http://homepage.eircom.net/~ei9gq/lpf.html