Breaking in the new Elecraft AX2 during a short POTA activation

As I mentioned in my recent AX1 vs AX2 video and blog post, I purchased an Elecraft AX2 antenna and bi-pod in late January (note: two days before Elecraft announced their February ’23 sale price! Doh!).

I received the AX2 package a few days later and I was certainly eager to take it to the field.

My first opportunity came on Tuesday, February 14, 2023, when a short activation window opened up in the afternoon.

Zebulon B. Vance Birthplace (K-6856)

One of the first things I noticed after taking the AX2 out of the package is just how solid and compact it is. The AX1 is short, but the AX2 is a few inches shorter because the base is more compact.

Unlike the AX1, the AX2 is a mono band antenna, thus the coil only needs to accommodate one band. When you receive a new AX2, it’s configured for 20 meters out of the box, but the user can modify the coil to work anything from 20 to 6 meters.

“Resonant-ish”

Even though I mentioned this in my AX1 v AX2 article and video, I’d like to reiterate that the AX2 is nearly-resonant on 20 meters. It is not reliably resonant.

I’ve still been receiving a lot of messages from readers stating that their AX2 and AX1 are resonant on 20 meters, so they don’t pack any sort of matching device in their field kit. They simply hook the AX2 up to their little QRP radio and hop on the air.

While it’s true that these antennas may provide an acceptable SWR most of the time, you really can’t rely on a solid, reliable match as you could with an end-fed half-wave.

I’ll repeat what I mention in a previous post:

Small verticals like the AX1 and AX2, that use coils to electrically “lengthen” the antenna, have a higher Q than, say, a large aperture quarter or half wave antenna. In practical terms, this means that the window of resonance is narrow and more fickle than, for example, an end-fed half-wave.

A lot of factors can affect the SWR on higher-Q antennas like the AX1/AX2 including:

      • the type of terrain,
      • height off the ground,
      • length of counterpoise,
      • configuration of counterpoise,
      • and, most notably, the operator’s own body capacitance.

You may find that the AX2, for example, is natively resonant on 20 meters at one location, but isn’t at another location. This is quite normal. It’s also the reason why Elecraft states that both antennas are designed to be used with an ATU.

So there you go! If I hook up my AX1 or AX2 to a radio, I’ll always have some means of matching the impedance–either an external ATU, or a capacity hat. You can also tinker with the length of the telescoping whip and counterpoise to tweak the match.

The important part–especially if pairing these antennas with a radio that lacks both an internal ATU and SWR meter (say, the MTR-3B, G106, or TR-35)–is that you’ve some means to check the SWR before conducting a long activation session.

Setting up

For this activation, I was pairing my new AX2 with the Elecraft KX2 which sports a superb internal antenna tuner, so finding an acceptable match was not going to be an issue.

Set up couldn’t have been easier. Simply 1.) attach the 13′ counterpoise to the KX2, 2.) screw the telescoping whip on the AX2 base/coil, 3.) attach the right angle BNC adapter to the base, 4.) attach the bipod bracket and extend the bipod legs, 5.) then attach the AX2 to the KX2. That’s it!

All that’s left to do is find a clear frequency on the 20 meter band, then hit the ATU button on the KX2 to sort out any impedance mis-match.

Gear:

I’ll be the first to admit that the Begali Traveler must be one of the most photogenic field keys on the market!

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On The Air

I started calling CQ POTA and within the first twelve minutes on the air, I worked the ten stations necessary to validate this activation.

I continued operating for eight more minutes and worked ten more stations for a total of 20 stations logged in 20 minutes.

Dang!

Let’s just say that the AX2 certainly impressed me on its maiden voyage.

The sad part, once again, is that I had to sign off with still a load of stations trying to call me. I had truly reached the maximum amount of time I could stay on the air and not be too late picking up my daughters after their class.

QSO Map

Here’s what this 5 watts into a 4 foot antenna activation looked like when plotted out on a QSO Map.

Activation Video

Here’s my real-time, real-life video of the entire activation.  As with all of my videos, I don’t edit out any parts of the on-air activation time. In addition, I have monetization turned off on YouTube, although that doesn’t stop them from inserting ads before and after my videos.

Note that Patreon supporters can watch and even download this video 100% ad-free through Vimeo on my Patreon page:

Click here to view on YouTube.

AX2 First Impressions

I don’t think I could have been more pleased with the AX2. I like how insanely compact this antenna is and how well it performed for me on 20 meters.

Speaking of which, these days, 20 meters tends to be the hottest band for both POTA and SOTA, at least here in western North Carolina during my daytime activations.

Depending on where you live, your mileage may vary.

Your mileage may vary using an AX2, AX1, or any tabletop travel antenna, in fact. I’m lucky that my normal 20, 30, and 40 meter footprint includes the majority of the amateur radio operators here in the eastern half of North America.

We posted recently about how Terry had mixed results using his AX1 antenna in Oregon. When your compromised antenna propagation footprint falls on sparsely-populated regions, it might take more time to rack up chaser/hunter contacts.

A lot of folks on that post noted (both seriously and jokingly) that some of my AX1 success has to do with my “celebrity” status. [First off, the use of the word “celebrity” in association with me is quite the exaggeration! Ha ha!]

That said, I get it. Some ops may enjoy working me because they’re a reader, YouTube subscriber, or maybe they want to hear what their station sounds like other the other end when I post an activation video. Frankly, it’s quite the honor for me that anyone would go out of their way to log me.

While I’m sure this factor may be in play to some degree, I’d argue it’s less than you might think.

When I operated the AX1 with my new Canadian callsign (VY2SW) in Québec last summer (photo above is one example), I found that I had the same amount of success despite not being as ideally located geographically. Very few people had VY2SW loaded in their Ham Alerts.

That said, if you live in a geographically-isolated region (in terms of propagation footprint) you will find that using a compromised antenna takes more patience and planning.

Here in the eastern half of North America? I feel like compromised antennas are quite effective pretty much anytime if your goal is to simply complete an activation.

Thank you

Thank you for joining me on this short activation!

I hope you enjoyed the field report and my activation video as much as I enjoyed creating them.

Of course, I’d also like to send a special thanks to those of you who have been supporting the site and channel through Patreon and the Coffee Fund. While certainly not a requirement as my content will always be free, I really appreciate the support.

As I mentioned before, the Patreon platform connected to Vimeo make it possible for me to share videos that are not only 100% ad-free, but also downloadable for offline viewing. The Vimeo account also serves as a third backup for my video files.

Thanks for spending part of your day with me! Here’s wishing you an amazing week ahead!

Cheers & 72,

Thomas (K4SWL)

6 thoughts on “Breaking in the new Elecraft AX2 during a short POTA activation”

  1. I’ve been singing the praises of tabletop antennas for months now, and it seemed like, with POTA, they could do no wrong (QSO a minute on 20 meters was the norm, and nobody but my elmers have me in HamAlert, haha). But the other day I *really* struggled to make my activation and it was humbling. But it was still fun! It makes you appreciate all the hunters with good ears. Deploying a decent EFHW in the middle of the country sometimes makes POTA a little too predictable so the challenge is welcomed, hopefully it’s not too annoying for hunters. Thanks for the nice writeup, Thomas.

    1. Hi, Sam,

      Thank you for your comment. Yes indeed, there are going to be those times when you struggle to validate an activation.

      This has especially been the case over the past two weeks. We’ve had periods of complete radio blackout with cascading incoming CMEs, flaring, and all sorts of nastiness from our local star. Then again, we’ve had moments of recovery and amazing higher-band DX between these unstable periods.

      It’s quite possible your timing was poor. Then again, you have the right spirit: it’s a challenge and sometimes a welcome change of pace! I really like that. 🙂

      Cheers,
      Thomas

  2. Thanks for the review Thomas.

    My AX2 should be here the day after tomorrow according to the USPS. I’m hoping mine works as well s yours did.

    it looks like our house hunting has come to an end (as long as the inspections go well). We will be ending up between Columbus and Lake Lure if nothing goes wrong.

    It will be nice to have some time to play radio and have outdoor antennas again.

    73
    W4MKH
    https://w4mkh.com

    1. That’s a beautiful part of WNC, Marshall! And there are lots of hams in that area, too. My fingers are crossed that it works out!

      I should think you’ll enjoy the AX2–it works quite well in North Carolina.

      Cheers,
      Thomas

  3. Great video Thomas. I have an AX1 and have not had much luck with it, but I have not used it much. I will be working with it on the 25th at a park. I think this Florida sand is not so good for small vertical antennas, hi. I have always been concerned how I deploy the counterpoise wire. 73, ron, n9ee/4

  4. I’ve heard varying reports on how antennas like these work, from the AX1 and AX2 to the lunchbox style antennas. I think the major problem come with people not understanding that ALL antennas have rules, and beyond design and build, some of those rules involving when is the best time and/or place to use them. I don’t care how efficient/low-Q a monoband wire dipole is, sometimes, there’s just not enough room to effectively deploy them, especially on the lower wavelength bands. You also take your chances trying to use a low-takeoff angle antenna in a canyon. But I think if you keep the rules in mind, you can find plenty of great opportunities to use an antenna like this.

    BTW, Tom, your “celebrity” status might have had something to do with the fact that that Elecraft had to take three weeks to get my AX2 out the door. I’m not complaining, though. I’m “I remember when shipping used to be 6-8 weeks” years old, so I just roll with it. It’s slated to arrive on Thursday, and I’ve already got a POTA lined for the St. Pats weekend to use it.

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