Magnetic Loops
Links and info for Active Magnetic Loops
Wellbrook Model ALA1530
https://active-antenna.eu/amplifier-kit/
Model RF PRO-1BLN-2
http://www.lz1aq.signacor.com/docs/fa-eng/Weak_signals-mag_loop_engl.htm
https://www.nonstopsystems.com/radio/frank_radio_antenna_magloop-slinky.htm#top-of-page
http://www.lz1aq.signacor.com/
SDR Links
https://www.sdrplay.com/ - for SDR Play receivers
https://airspy.com/
https://www.sdr-radio.com/console (independent & recommended)