When is an end-fed antenna not really an end-fed antenna?

On the HamRadioHelpGroup mailing list, there was recently a discussion of end-fed antennas. One guy wrote:

I plan to use a QSO-King end-fed antenna with my new Kenwood TS-590. Does anyone have any experience with this antenna? I’ve read good reviews from many people.

I chose this antenna for several reasons. The biggest is that I lease my house and this will have the least physical impact on the house. It will also be relatively unassuming. I will string this between two telescoping antenna masts that I can stick in the ground and attach to each side of the house.

Well, after taking a look at that antenna, I replied:

I’m not so sure that I’d believe all the claims that he makes for this antenna, but you should be able to make some contacts with it.  Most end-fed antennas are single-banders with a matching network that provides a match to 50 ohms on that band. This guy’s just using a balun to bring down the SWR to something that your rig’s internal tuner can match.

Instead of spending 70 bucks on this thing, why not buy some ladder line and antenna wire and make your own end-fed Zepp antenna?  Google “end-fed zepp” for plans. Using ladder line will be a lot more efficient than using coax.

The “QSO King” is an end-fed antenna, but it’s not an end-fed, half-wave (EFHW) antenna that most us think about when we hear the term “end-fed.” I’m not even sure what you’d call this antenna, except maybe an end-fed random wire, with a balun connected to it to try to bring the SWR down to something than a rig’s internal tuner can match.

Another ham, who’s noted for more caustic remarks than I usually make wrote, [The antenna's Web page] “cleverly interlaces demonstrable facts (like the voltage withstand of Thermaleze wire and waterproof enclosure) with subjective and anecdotal statements of performance. No where in his ad does he state any measurable performance parameter.”

In response to the statement in the ad, “Important Note : The antenna works best if the coax is at least 33-ft. long,” this same guy wrote, “Warning, Will Robinson! Beware the design that requires a specific feedline length. It can only mean it’s radiating, or it’s ballast.”

Finally, he advises, “If all you’re looking to do is run a tuner-fed random wire with or without a radial or counterpoise, just run the wire, jack it into the tuner and be done with it. No point in sending this guy money just to get the same (or worse) result.” Amen.

Comments

  1. Can’t speak for the antenna since I don’t have one. However LNR Precsion sells end fed antennas with an UNUN similar to the QSO King. The LNR antenna gets 5 out of 5 at eham. Not a bad thing said about it. It would appear the QSO end fed work work equally as well.

    As far as a specific length for the feedline. It would appear he is just trying to achieve an adequate counterpoise. DX Engineering also comments that for their 43 foot all band vertical that one should use at least 150 feet of coax.

    I’m no expert by any means but I really don’t see anything askew with the antenna but then again I have been known to be wrong in the past :)

    • Dan KB6NU says:

      The boxes at the ends of the Par EndFedz antennas sold by LNR are not ununs, but rather matching networks. The EndFedz and the QSO King are really two quite different antennas.

  2. What difference does it make if it doesn’t compare to an antenna that YOU might like or support financially as long as it works as they say it does. I have used this “QSO-KING” antenna for a long while now and have ran 1kw through it and have made contacts in Australia, Japan,New Zealand, and several more long distant contacts with great results and no problems. Unless you can prove that it does not work or does not do what they say it will do then your word is only hearsay. Get your facts together first before putting someone elses product down.

  3. Dan KB6NU says:

    The gentleman asked for a technical opinion on the QSO King antenna, and we gave him one. I did say that he would be able to make contacts with it, and you proved me right.

    The difference it makes is that instead of spending $80 on this antenna, you could spend it on parts to make your own antenna–one that would work even better.

  4. Jim Lokken says:

    The antenna works great for me. I am using 72 feet of wire set up as a flat “V” configuration due to HO restrictions. It does generate some stray RF that sets off my emergency phone dialer and body capacity touch lights. I feel this is fair tradeoff for the performance and I can take this antenna down in a matter of minutes.

  5. I would agree that this antenna might not be an ideal situation nor would it perform necessarily as well as a regular dipole cut for a certain band. But many operators out there cannot put up dipoles due to either HOA restrictions or lots that will not accommodate such antennas. So for these hams, antennas like the QSO KING and their variants are the best way to get “on the air” , although be it with a compromise antenna. I have personal experience with the PAR Endfedz EF-40/20 and these have done quite well for me.

    • Dan KB6NU says:

      Well, I think charging $80 for the QSO King is a scam, especially since you can build a real end-fed antenna for less than $15. Heck you could build five or six of them for the price of one “QSO King.”

  6. Maybe you could build it cheaper. This antenna works.

    • Dan KB6NU says:

      What antenna works? A “QSO King”? I don’t doubt that. Nearly any piece of wire will work. You don’t have to pay 80 bucks for a piece of wire, though.

  7. Dan KB6NU says:

    Since posting this, I’ve built an end-fed, half-wave antenna for 20m that works great and only cost me about $10. See http://www.kb6nu.com/kb6nu-finally-builds-an-end-fed-half-wave-antenna/ for more details.

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