John Portune (W6NBC)

Optimizing the Magnetic Loop Antenna

by John Portune, W6NBX

January 20th, 2024

Excerpt from regular meeting minutes

We were to have had a live talk, “Optimizing the Magnetic Loop Antenna,” by John Portune, W6NBC, from Los Angeles, California.  But sadly, due to a time zone misadventure, John didn’t make it in the 10-11 am hour.  John sent an email apology with a willingness to set up another talk day/time.  Carson had a Plan B, and aired a YouTube recorded presentation of John doing this talk in the past.  There are several such recordings of John’s mag loop optimization talk on YouTube.  

Some links [are included below.]

John is a great teacher and an innovative ham antenna designer.  His recorded talk was great and worth a watch for those who couldn’t attend today, but we missed his live spontaneous charisma and off-the-cuff ham brilliance in Q&A.  It must be said that John is quite emphatic about his design mag loop being optimal over all others—and in the recorded talk we watched he hammered that nail in hard.  Carson is finishing a build that is based on John’s original design, and will report on results as they transpire.  It’s a great design.  But Carson is a bit more laid back on the subject, with the view that if a mag loop antenna works to consistently make solid ham contacts to meet the ham’s radio goals then it’s a good mag loop!  Don’t tell John I said that…    

Optimum Magnetic Loop Antenna

Mag loops are very popular, but few are optimized for size, shape, performance, cost, building material or neighbor and HOA appeal. This presentation critically but briefly examines ALL the factors that make up an optimized mag loop, and also presents an example, a low-cost optimized PVC and foil tape loop for the largest majority of hams.

John Portune, W6NBC, on Mag Loop Antennas

Prolific ham radio researcher and inventor John Portune, W6NBC, spoke to W6SD, the San Fernando Valley (CA) Amateur Radio Club in July of 2023 about construction and use of the (incorrectly named) magnetic loop antenna.

How to build an "Optimum" Magnetic Loop Antenna

Mag loop have been wildly popular since their appeared in ham radio in 1968. Yet working from “guess and golly” internet designs, disappointment has not been uncommon. Here are the six main factors needed to optimize all mag loops, plus a quick look at two low cost full-limit high-efficiency optimized PVC and foil tape designs: 10 through 40-meters and a compact version for 6 & 10-meters. Also, no expensive vacuum variable or heavy-duty rotary capacitors required.

This presentation was made at the QSO Today Virtual Ham Expo.  For more information go to: Also visit the QSO Today Podcast for 1 hour interviews of ham radio operators who make these presentations: