The Small Unidirectional Loop Antenna (SULA)

[A.Z.]

after some months of fiddling, simulating and field testing, this (receive only) antenna is finally ready for anyone willing to try it

https://swling.com/blog/2022/08/introducing-the-amazing-sula-an-affordable-unidirectional-dx-grade-loop-antenna-that-you-can-build/

no miracle antenna, mind me, just the result of an idea which became a NEC model, a real thing and got refined and improved through a process which started months ago; if someone is curious, the whole "evolution" of the idea can be found here

 https://swling.net/viewtopic.php?t=47

again, no miracles, just a small unidirectional antenna covering the whole HF bands and pretty good on V/UHF too, for the ones willing to try it, the latest design (along with the NEC model) is here

https://swling.net/viewtopic.php?p=411#p411

notice that while we (me and Ollie) used off the shelf components, nothing forbids one from using homemade ones, just... if someone will decide to try it, some feedback will be welcome

[mag_therm]

Neat job.
I played with loops about that size at VLF, but multiturn and resonant.
If I ever get on 630 m (5 W eirp limit) I will first try a loop like that.
At that frequency , resonant ferrite rods are also usable , having sharp nulls.

[A.Z.]

the SULA is a RECEIVE only loop and it has ONE main (cardioid) lobe and ONE null, as opposite to regular loops which have an eight shape pattern, plus its vertical aperture shows a low angle good for DX signals

[A.Z.]

for the interested ones, the 3rd part is online, full infos about building the SULA can be found here

https://swling.net/viewtopic.php?t=55