Antennaes

[Nemo]

Thoughts Gents?

Nemo

https://theprepared.com/blog/km4ack-antenna/

[JohnyMac]

Looks like fun. I have a similar end fed antenna I use for backpacking.

[Jackalope]

     It's an end-fed antenna, so it's a compromise antenna.  It would be good for portability, but I question its durability.  Some of the end-fed antenna designs are already very compact, so I don't see this as an improvement over existing designs.  I don't want to put down the author of the article, but...  he sure had a lot of problems with a basic, simple antenna.  The author, Josh Center, attempts to compare it to the Chameleon commercial antenna, which costs considerably more.  However, the consumer is paying for a ready-to-go product that doesn't require extensive experimentation. Center depicted some of the weaknesses of the KM4ACK design, like the SO-239 not being in a fixed position.  The weaknesses could be resolved, but there are better,existing designs out there, like this one: http://www.earchi.org/92011endfedfiles/Endfed6_40.pdf 

     I don't have any pecuniary interest in either antenna product, as I have made several end-fed antennas which have served me well enough.  End-fed antennas are notable for their ease of installation, size and relative simplicity.  End-feds are not noted for their performance... they work, but there are other alternatives.  Experimentation with antennas is one of the great facets of amateur radio.

      Getting back to Nemo's post, the KM4ACK end-fed antenna would not be among my top three choices for a portable HF antenna, even among other end-fed antennas.  If you're looking for an end-fed antenna kit, the ARRL has one that has assembly videos, etc.: https://home.arrl.org/action/Store/Product-Details/productId/133267

[pkveazey]

I hate the END FED HALFWAVE antennas. Now that I've said that, I hear a ton of them on the air and they appear to work. Hmmmm..... Is it that they work or is this just another stupid thing like everybody had to build themselves a damned J POLE for 2 meters. I personally have a RADIO BUG OUT BAG with two 100' spools of insulated wire, some Coax Cable, an ICOM 718, 100 watt HF transceiver with an attached LDG Autotuner, Multimeter, Antenna Analyzer, Connectors and Adaptors, Soldering Iron and Solder, and some more crap too numerous to name. My main complaint with antennas that are not in the 50 to 75 Ohm range is that they can be a bitch to get them to operate correctly. Hell, when I lived in the city on a 1/4 acre lot, I ran a 125' long wire antenna with a Ground Rod driven in the ground just outside my window. Well, Duhhhh, of course I had to use a manual antenna tuner so I could operate on all the bands. It worked OK but now that I'm out here in the country, I use a bunch of antennas for the different bands. An End Fed 1/2 wave isn't one of them. I'm reserving Judgement on the End Fed Halfwave because they seem to work.

[Sir John Honeybucket]

My favorite multiband antenna for QRP/portable is a linked dipole.  In almost all cases, I find stringing a dipole no more difficult than an end fed half wire (EFHW)e.  Here is a fine example of a store-bought variant for 40/30 & 20 meters. They also sell a four band  80/40/30/20  for those who would prefer to not have to build one.  Before anyone says ' Sir John, you have obviously never strung a wire in tight trees'. . . uh, yes, as a matter of fact I have and did it professionally when failure would likely be lethal as well as a civilian backpacker in high and rough country - did it for decades, bought the shirt and wore it out.  I like EFHWs, and keep a few on hand (I especially like the TUNABLE variant from QRPguys) , but a dipole is my first choice.


- Sir John Honeybucket

Ps.  I'm making a linked dipole for a friend right now. illustrations are easily found on the internet.