A Portable Linked End-Fed Half-Wave (EFHW)

UPDATE 15 August 2023: I’ve accomplished some testing to determine if the eyebolt used in this design introduces stray inductance or capacitance. Read about that testing here.

Starting in the fall of last year, I began working on a linked EFHW for portable HF radio. Almost all of my amateur radio activity revolves around portable ops. Parks on the Air (POTA) is a major interest as well as keeping my skills sharp for the unexpected.

As many portable operators have found, the EFHW is often the ideal balance of portable convenience and efficiency. I wasn’t satisfied with commercially available products, however, as I wanted an antenna with more control over the radiation pattern and a rugged build to match the needs of an adventurous field operator. Thus this project was born.

Rather than just copy existing designs, I made an effort in the project to further my understanding of the properties of EFHW antennas and use the latest build techniques and materials for improved efficiency. This effort builds on suggestions published by Evil Lair Electronics on YouTube, Owen Duffy, VK1OD, and Colin Summers, MM0OPX.

I’ve attempted to document all my findings in a comprehensive paper. The current draft is located in the Files section on this site. I still have a number of goals for this project so stay tuned for updates in the coming weeks and months.

I would very much welcome feedback on this project if you have suggestions for improvement or if you found this useful.

Padre