Also, inspired by your post, I dragged my OM0ET magloop up a mountain today for a POTA activation. I used a 3D printed tripod adapter of my own design that allows me to mount it on the collapsing legs from the Buddistick Pro. It makes the whole package a lot more manageable and light weight than carrying a camera tripod.
I had a successful activation of K-4454 on 20 meters, and thought you might enjoy some photos of the setup:
I’ve uploaded the design to Thingiverse at this address:
Wow! Thank you Jonathan. That short demonstration prompted me to order the K7QO noise bridge kit from QRPguys this morning. In fact, I plan to build this and keep it with my loop antenna as it’ll pair so nicely with my IC-705 and TX-500!
Thank you, also, for sharing those 3D files! I love that field setup at K-4454!
I’ve used this loop a few times in the field and even once from inside a large brick community building while doing an FT8 demo.
Loops are a brilliant solution when you have:
QRM from local noise sources,
limited space to deploy an antenna,
or need a very low-impact and small footprint antenna (very handy for those historic and archeological POTA sites).
The trade-off, of course, is that they have a high “Q”–meaning very, very narrow bandwidth. Basically, anytime you move frequency? Yeah, it’s time to re-tune.
The environment around a loop can also have a pretty significant impact on your ability to tune it as well. For example, metal support structure in a building, window frames, metal poles, vehicles–anything like this nearby can have an impact on your ability to tune a loop and obtain a low SWR.
It’s for this reason I use them so little in the field–where I live, wire antennas are so easy to deploy and use.
But sometimes loops are the perfect tool, so knowing how to efficiently and effectively use them is important.
The F-Loop packed
I thought I had posted an activation video using the F-Loop, but looking back I realize I have not.
Yesterday, I decided to pack the F-Loop in my larger Spec-Ops Brand T.H.E. Pack which can easily hold the entire loop, folding tripod, and antenna analyzer.
I always fully set up an antenna before packing it in a new pack just to make sure I’ve included all components. I used this as an excuse to improve my loop tuning skills by intentionally chasing POTA stations across the HF bands. I worked all of the stations I hunted (five, if memory serves).
Twice I obtained a brilliant match just by using my ear (listening for the HF band noise level to increase as I tuned the variable cap) and the rest of the time I turned to my RigExpert handheld analyzer to find a low SWR.
I’m looking forward to taking the F-Loop to the field soon just to see how well it performs. After my practice today, I do believe I’ll keep the antenna analyzer packed with the loop–it makes it so easy to find a good match.
I find the F-Loop a wee bit easier to tune than my W4OP loop. The W4OP loop is also a brilliant loop if you can find one–I recently gifted mine to a friend. Here’s my review from a few years ago.
I’ve used an AlexLoop once and was impressed as well. That’s another antenna I may review at some point.
Commercially-produced mag loops are pretty expensive though. I do plan to build a 20M mag loop antenna before end of year. They’re surprisingly easy to build if you have a good variable cap.
Curious how many of you regularly use mag loop antennas. If you do, what make and model? Or is your loop homebrewed? Please comment!
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Many thanks to Jonathan (KN6LFB) who shares the following in reply to my recent post about tuning mag loop antennas:
