Field Research on Portable Antenna Setups (POTA / SOTA Operators)

POTA, SOTA, and Other Activities
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Field Research on Portable Antenna Setups (POTA / SOTA Operators)

I’m conducting a small research project based solely on field data and empirical knowledge.
As radio amateurs, we all know that some things look perfect on datasheets — yet perform poorly in real conditions, and vice versa.

Based on your real-world experience in POTA, SOTA, or any field activity, I’d love to hear your insights:

1. What type of antenna do you mostly use in the field?

  • End-Fed Half-Wave (EFHW)?

  • Vertical?

  • Random wire antenna?

If you use EFHW:

  • What length of coax do you typically run?

  • Do you use an RF choke?

  • Do you add a counterpoise (if your design allows it)?

  • Is your EFHW for 40-20-15-10 m, or is it cut for a single band?

  • In what configuration do you use it most often: vertical, inverted-V, sloper, or horizontal?

If you use a vertical:

  • Do you use a ¼-wave with radials?

  • How does it perform on rocky or uneven terrain?

  • Have you tried any loaded or coil-based verticals?

I know it’s a lot of questions — but the goal is to collect meaningful data and share real experiences from the field.

For reference, my current setup is an EFHW for 40-20-15-10 m, about 20 m long, used in an inverted-Vconfiguration due to space limitations.
I run ~12 m of coax, no RF choke, no counterpoise, and I have no issues with RF feedback or SWR drift. My typical SWR is below 1.3:1.

I’ve noticed that slopers seem a bit more directional, but in practice the difference is minor. I’ve built and tested many EFHWs, both homemade and commercial, and I’m convinced that the real “magic” lies in the ferrite core — its material and size.
A good medium-sized core won’t saturate like a small one, and large cores made from poor materials are just as bad.

I use a 49:1 transformer with the usual 14 turns, and while wire gauge (AWG) might slightly affect bandwidth, it’s mostly negligible.

Looking forward to hearing your experiences and results — there’s no single “right” way to do things, and that’s exactly what makes this hobby so fascinating.

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  • What length of coax do you typically run? I have a 25’ and 6’ length in my bag, it depends on the antenna placement.

  • Do you use an RF choke? No, but I want to start. I have just purchased one.

  • Do you add a counterpoise (if your design allows it)? No, I can’t think of a time when I did this.

  • Is your EFHW for 40-20-15-10 m, or is it cut for a single band? Mine is 40-20-10.

  • In what configuration do you use it most often: vertical, inverted-V, sloper, or horizontal? Usually horizontal or sloper, depends on where I can mount the feed point side.

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Thanks!

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I do portable in my front yard occasionally as the backyard has close houses and overhead power lines. Noise floor is like S7 here all the time. I’m also running FT8/FT4. :slight_smile:
So for cheap and performant, a speaker wire Rybakov out of (“Salty Walt”) K4OGO’s book has been amazing for what it is. 25ft(7.6m) driven element, a 4:1 unun, and speaker wire radials (I use 4 pairs of 2 @ 12.5ft(3.7m) made from the rest of the spool of speaker wire). Recently started experimenting using a 25ft whip so I don’t need to use the 10m pole. With it I’ve made contacts from the Chicago IL US area to New Caledonia, South Korea, Brazil, Romania, Japan, Ukraine Cyprus, Crete, etc.

My main “base station” antenna is a N9SAB Mini G5RV (40m multiband) in an inverted V in the backyard, held up with 80lb(36kg) fishing line strung out my top floor window with the other end tied to the fence. It’s just enough to get the feed point for the window feed line a fist above the ground so it can hang vertically. It’s basically a banana clip, some wire with reinforcements and some window line to do the matching. Weighs barely anything. No coil or balun, so I run 100w FT8/FT4 on it and it hasn’t burned up yet! :grinning_face:

I have others as well, but honestly the above two are great and use them for the majority of contacts.

Oh, I choke the Rybakov at the feed point but not the Mini G5RV and always choke at the amp/radio. And I use the tuner in my radio to run all bands 40m-10m if I need to correct for 2.0+ SWR for the above two antennas.

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Great, thanks for the answer. im use a 4:1 UNUN, very interesting results.

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