New HWEF articles!

I’ve written two new interesting articles about the HWEF:

New HWEF dedicated to 20/10 with single FT240-52 (updated 26-MAR-2020)
Yes! Finally succes! Because of the limited working range / bandwidth of the 1:49 autotransformer (UNUN), I’ve succesfully built an endfed tuned to high frequencies using a single FT240-52 with a 2:13 ratio that seems to – finally – work really really well!

HWEF: what toroid(s) to use?!
Everything I know/learned until know about designing the (in)famous 1:49 auto transformer / UNUN and how to optimise it to meet your specific requirements.