I don't think anyone can deny that an AX1 is a very convenient antenna, but isn't the elephant in the room still efficiency?
Looking at Doug's antenna, judging from the whip size, I'd guess it's probably about 7 feet long assembled.??
In theory, given the old radiation resistance increases with the square of the length truism, it's probably about 3-4 dB better than a 4 footer.? If it was 8 feet, it could be as much as 6 dB better.? And if you use a whip like the one on an MFJ 1898, you can get almost 7 feet of length that collapses to about 9 inches.? That's a little over 4dB better for way less bux, a little more effort, and just a bit longer collapsed antenna length.
And it's easy to attach to Doug's antenna or just a long whip to a KX2 with a little bracket like in the picture below. Maybe Howie could sell one.:)
The KX2 tunes the 1898 whip only configuration?thru 17 meters well, on 20 well enough, and if you add a 6 uH? coil, 30 works well, and an 18 uH coil 40 works well.? I'm just too cheap to throw away an easy 3 -4 dB when I'm already not that loud.
I'm not anti-AX1 or Elecraft, God knows Wayne has enough of my money.? But it would be fun to see a Super AX-1A that is more efficient, easily packed and exploits the superb tuner in the KX2 to its maximum benefit., I might have to part with more money then. :)
72 Scott ka9p
? ?Thanks Doug for the info. I¡¯ve been an active ham doing portable CW/QRP operating since the mid 1970¡¯s.? Back then I was hauling around my TenTec 509 with 2 6V lantern batteries and a fan dipole..then became a NorCal club member. amongst other activities including working with Russ Carpenter on the Adventure Radio Society. I¡¯m pretty familiar with most types of portable antennas,including a wide variety of verticals.? Not long after I built my K2 I became acquainted with Vern Wright W6MMA and his Super Antennas,and got the PW-1 (which I still have and it¡¯s superbly well made). I¡¯m very familiar with the concept that a larger vertical would have higher Q,and potentially be more efficient than a smaller one.? So-why would I continue to use something like the AX1 when a larger vertical would be better? Well..as they say a picture is worth a thousand words,and I¡¯ve attached a couple. What you see my version of the ¡®shack in a box¡¯ with KX2,AX1,AEX1, Begali Adventure paddle and assorted accessories including battery,radials, a random wire end fed and other assorted items. And you can see next to it the vertical we built based on your plans. The point of this is to show the size difference and all important form factor. Oh -and I forgot to include the tripod needed to mount the vertical. The AX1 doesn¡¯t need that I can mount it directly to the KX2. I figure I¡¯d need a bag about twice the size to carry the larger gear and extra mounting hardware¡ Here¡¯s the deal-the bag you see has been hauled around the world and hiked to numerous SOTA and POTA sites since 2016. Is the AX1 less efficient than the larger vertical? Yes, but I wouldn¡¯t have taken the larger one due to size and weight requirements. The small bag allows me to take the radio practically anywhere in the world,just tucked into a corner of my carryon or suitcase,and I can be set up in about 2 minutes or less. And the very low profile of the AX1 is ideal for many locations where otherwise I¡¯d probably not set up and operate. And that stinkin¡¯ little antenna has made thousands of DX , S2S and P2P contacts worldwide-Wayne & Co. at Elecraft have made it as efficient as possible given the size. ? Regardless of where or when I operate I always try to use the ?best antenna I can reasonably carry. If I¡¯m traveling by car,then I can definitely take a bigger unit,and I have a bunch of great options. Same when hiking to a summit-carry as little as possible to get the job done. It¡¯s ultimately a matter of trade offs. Given all of these factors the small package and flexibility of the AX1 is for me a good trade off for some less efficiency,and the difference between taking and operating in many situations. For some folks the cost is an issue but for me spreading out the initial outlay over the past 9 years($11/year )is a great balance. I don¡¯t mind paying a fair price for well made item that gives me lots of use. I have operated in many interesting places and in situations where a larger setup wouldn¡¯t be possible. And now with the KH1 (which has the same antenna) it¡¯s even easier to travel and operate. Money very well spent in my opinion. I often ask hams- ¡®do you want to operate or equivocate?¡¯ ? 
Dan Presley 503-701-3871 danpresley@me. com?
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Are there plans online for the homebrew antenna?
Thx
John KY4WW
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Dan, the small form factor is part of the problem.? ?It's diameter is half the one of the homebrew version.? The larger the coil diameter,? the greater the Q, which is directly related to the efficiency and effectiveness of the antenna.? The homebrew version
you built (for less than $10)? takes very little more space.? ?I have had one in my small bag for years.? I just can't justify paying $100 more for an inferior antenna.? I have done sided by side comparisons of two antennas and the homebrew one wins every
time.? Facts are facts.? The AH1 is well built and looks good.? The homebrew one works better and is $100 cheaper.? And they? both fit in the bag.
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Can't wait for Pacificon.?
Doug
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