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Author Topic: PA3GZK active receive loop  (Read 2670 times)

Offline Corvus

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PA3GZK active receive loop
« on: November 13, 2017, 0418 UTC »
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:

PI4NOV (in Dutch):

Low Pass Filter:
« Last Edit: November 14, 2017, 0517 UTC by Corvus »
Leeward coast, Island of Hawai'i

Offline ChrisSmolinski

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Re: PA3GZK active receive loop
« Reply #1 on: November 13, 2017, 1218 UTC »
I've never built a shielded magnetic loop, but have been meaning to give it a try. I'm tempted to build two loops of that design and use them with my LZ1AQ amplifier, which presently has two aluminum foil wrapped hula hoops as the antennas.  Thanks for sharing the links.
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 300 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree