as shown here:
This is very simple to build:
You need Jan´s PCB or my PCB for the broadband transformer 1:49:
https://github.com/DG1JAN/UniBalun
Update 09.Sept 2022:
Jan has updated his PCB and has now also the Gerbers on his GitHub. To be sure to have the latest Revision, please donload the Files from his Github.
End Update
Alternatively, you can use this PCB designed by myself (using FT114 core instead of FT82):
How to wind a Broadband-Transformer and the theory behind it is explained here:
Then you need exactly 20,5m of DX Wire Ultralight:
https://www.dx-wire.de/dx-wire-antennendraehte-litzen/dx-wire-ul/
And i used DX Wires „Dyneema“ 1mm rope as well as 1mm Bricklayers string.
Print files for Spool are found here:
https://www.thingiverse.com/thing:4149904
Scale to 130% in your slicer, so it will be around 110mm long.
Print Files for the Pocket Version of rope tensioners, insulators etc are found here:
