Static charge on my EFHW?

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by WB2IOL, May 24, 2019.

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  1. AJ6O

    AJ6O Ham Member QRZ Page

    I have the exact same antenna and CMC choke from the same company. I run 600 watts through both of them all the time without any problems.
     
  2. WB5WPA

    WB5WPA Ham Member QRZ Page

  3. WN1MB

    WN1MB Ham Member QRZ Page

    Bingo!
     
  4. K6BRN

    K6BRN XML Subscriber QRZ Page

    And on another post he says its hooked up to an amplifier.

    https://forums.qrz.com/index.php?threads/placement-of-common-mode-choke.658450/

    Comprende, amigo?

    Well... I'm a user and I'm always game for exactly that. And have even USED the antenna (which you have ... NOT), multiple copies in multiple places... So, lets just get it up more than 1/4 wave and find out. Who's bringing the antenna and paracord?

    Also, you may ask WA7ARK. He's doing a paper on and has taken some data.

    Regardless, it goes up easy and works. Maybe the seller is just REALLY tired of abuse from the peanut gallery over a product that pretty obviously ... works? And has a lot of happy users.

    Brian - K6BRN
     
  5. AI3V

    AI3V Ham Member QRZ Page

    No Brian, you are selling them, you bring 'em.

    Rege

    P.S. My simple homemade , open wire fed, doublet shows exactly zero change in vswr regardless of power.

    Its a inverted v, about 180 feet long (that's how far the property line is), about 60 feet at the apex (thats how high the branch I could throw the weight over is), and the feedline is about 70 feet long (thats how far the radio shack is)

    The antenna is made of #14 stranded house wire from Lowes (about $40 for a 500 foot spool), the rope on the ends and in the middle over the branch is some yellow poly from Harbor Freight (about $16 for 600 feet), the center insulator is a foot long scrap of pvc? Pipe, and the line spacers are made form some sort of white plastic tubing from the plumbing isle at Lowes ( about $3 for a 5 foot length, I used 3 lengths cut into 6" pieces for spacers.)

    Are you sure you want to meet in public and have a eirp vs $ shootout?

    Rege

    P.P.S. I run a Ten Tec corsair, and the matching Ten Tec "tuner" , and I get the OWL into the shack by sandwiching it between two pieces of Styrofoam and close the windowpane on it. I connect the line directly to the "tuner". As it has a built in "balun". Curiously Ten Tec dosn't mention the balun ratio in the instruction sheet for the "tuner" (model #228), and I never bothered to figure it out.

    This set up tunes to a 1:1 vswr at the transmitter on every frequency between 1.8 and 29.7 mhz
     
    Last edited: May 25, 2019
  6. WG7X

    WG7X Premium Subscriber QRZ Page

    Been there, done that.

    Burnt up at least two baluns running RTTY. Saturation of the ferrite cores is real, repeatable and more prevalent with constant carrier modes.

    The OP has gotten very good answers as to why and how this happens. I that I can add is an anecdotal "me too"!
     
  7. WB2IOL

    WB2IOL XML Subscriber QRZ Page

    Well, thanks to all for the great info. It makes sense that an excess of power pushed the transformer beyond the Curie Point, causing core saturation and some permanent damage. The SWR problem subsides somewhat after a brief cooling period but is quick to return upon reintroduction of power, lower frequencies and higher power being the worst offenders. Since I'm switching to homebrew antennas from store-bought products, I plan on building a 49:1 transformer that will withstand greater power levels while raising the wire as much as possible to avoid nearby objects. I've learned a lot! Thanks again.
     
  8. K6BRN

    K6BRN XML Subscriber QRZ Page

    Rege (AI3V):

    You keep changing the rules! I thought this was an "efficiency" shoot-out.

    You and I live in very different worlds. In yours, $100 or $200 is a fortune. In mine, its dinner. So I would not bee too interested in cost shootout where the expensive item is relatively cheap compared to other antennas and your antenna is built out of scraps.

    All I could really say is: "Bravo! Well done! Very creative solution to a problem with absolutely minimal budget!". Fun. But irrelvant to me and many others.

    I'm more concerned with good utility/effectiveness, reasonably high power limits, stealth and ease of installation. That's REALLY what makes the EFHW family of antennas very popular. They've never been "the best" possible antenna - THAT question is never digital (yes/no).

    Am I selling them? Nope. No kick back. Danny just could not afford me even if he wanted to. But... I wish these same forums had provided the possibility when I was looking for a good "fill antenna" for 30M and 80M in CA, or for a stealth antenna in CT. Instead, it was the good old "sneakernet" and friendly, local hams who introduced me to these antennas.

    And when the "peanut gallery" started out attacking the antennas, and Danny, who is a VERY nice and easy to work with person, in my experience, I felt it necessary to balance the situation. especially as the vocal naysayers had never even used the product. I did not want others to lose the opportunity to try and use this simple solution, especially if they were just starting out; putting up an antenna is a common roadblock for hams new to HF, or in an HOA.

    In reality, the peanut gallery was doing an enormous disservice to the ham community. All in the name of physics. Which they never really understood, anyway. Which is why the debate has raged on over the years.

    Then WA7ARK actually had the b*lls to buy and test one and publish the results. I guess you know what he found. It's a pretty good antenna. Not perfect. Not the best. But easy to put up, performs pretty well in a good instllation, very forgiving.

    Thank you for the opportunity to "stand on my soapbox" once again. I can always count on you as a "straight man", Rege. You are very helpful.


    Brian - K6BRN
     
  9. AJ6O

    AJ6O Ham Member QRZ Page

    Check out balundesigns.com. It is my opinion they make the best value baluns.
     
  10. WA7ARK

    WA7ARK Ham Member QRZ Page

    And you have evidence/measurements for that statement? Or is this just a "feeling"?
     

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