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V55V's Rhombics - A Big Signal Out of Africa!

Discussion in 'Amateur Radio News' started by DK7PE, Mar 9, 2018.

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  1. DK7PE

    DK7PE Ham Member QRZ Page



    V55V in Namibia has one of the biggest signals out of the southern part of Africa.

    For over 20 years this station was improved. The farm has 26000 hectares and there is absolutely no space limitation. Martin (V51MW) says, he has tried all possible antenna systems and he is convinced that his Rhombic Antennas are best.

    He uses three of them, two with 160m each leg beaming into USA and EU. A third one has a side length of 80m looking into EU. The gain of these systems reaches up to 10dB and even more, depending on the band used.

    V55V was used for countless Contest and DXpedition activities during the past years. A big Signal was guaranteed!
     
    Last edited by a moderator: Mar 9, 2018
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  2. G6YZC

    G6YZC XML Subscriber QRZ Page

    I happily remember V51E working 3A2LU on 2m TEP in the early 90s. V51E was using his 160m ant on 2m whilst 3A2LU was stuck with a 15 ele 2m yagi. It clearly showed the antenna space difference between Namibia and Monaco HiHi.

    Imagine what can be done on 2m TEP these days with WSJT modes.....

    N2EME
     
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  3. W6RZ

    W6RZ Premium Subscriber QRZ Page

    V51E is my best DX on 6 meters. 9800 miles or so. Worked on 3/9/91.
     
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  4. AB9TX

    AB9TX Premium Subscriber QRZ Page

    I like the tower with weeds growing out the top. Looks natural.
     
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  5. MI0YLT

    MI0YLT Ham Member QRZ Page

    Wow amazing antennas love rhombics but the scenery is absolutely stunning and the wildlife especially the elephants ahhhh!
    Great video on so many levels.
     
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  6. 2E0FYR

    2E0FYR Ham Member QRZ Page

    Greetings to Namibia lived there for 17 years back in sunny blighty now :(
     
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  7. KR3DX

    KR3DX Ham Member QRZ Page

  8. K7LZR

    K7LZR Ham Member QRZ Page

    ......And along come the antenna experts complete with mathematical & graphical data to show why it can't really work well. Yup, better keep it real.
     
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  9. AK5B

    AK5B XML Subscriber QRZ Page

    OK, while I agree with your statement above W8JI's article is really more about dispelling the myth of extremely high gain and points out the advantages as well as the disadvantages of rhombics over dipoles and Yagis in simple, easy to understand terms. Basically, Tom is stating that when compared to a dipole at the same height and ground conductivity the actual gain is around 6 dbd---still very respectable and rewarding but not earth-shattering, either. It's always good to know the facts and not be misled by hyperbole in any case.

    He also points out several distinct advantages that rhombics have over Yagis, too and his article certainly does not detract one bit from my desire to be able to have one and use it so successfully as V55V has done, either.

    I have lusted after rhombics ever since I was a kid (early SWL) and will continue to do so. It never hurts to dream and to aspire to something greater than we might realistically achieve, in my opinion.

    What a superb video!

    73,

    Jeff
     
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  10. KR3DX

    KR3DX Ham Member QRZ Page

    That was exactly my intent when I posted the link to Tom's article. I wanted to show the realities of the rhombic antenna, I don't want to promote a lot of myths, conjecture, hyperbole, anecdotes, assumptions, and old wives tales about antennas. Another good article on Tom's website about how antennas perform and how people perceive that performance is here: http://w8ji.com/gotham.htm

    73
     
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  11. AK5B

    AK5B XML Subscriber QRZ Page

    Thanks, Dennis; I'll check out that other link when I have more time---lots of good info on Tom's site, too.

    73,

    Jeff
     
  12. K7LZR

    K7LZR Ham Member QRZ Page

    Agreed and I'm glad that Tom's information doesn't detract from a person wanting to erect and use said antenna. Maybe I'm too jumpy these days because it seems like every time a good story comes along like this where somebody is proud of their antenna(s), then it gets attacked & picked apart before long......
     
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  13. W6RZ

    W6RZ Premium Subscriber QRZ Page

    I'm not going to argue about the science of rhombics, but I'll always remember ZS6DN's huge signal on 20 meters with his rhombic.
     
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  14. KR3DX

    KR3DX Ham Member QRZ Page

    Keep in mind that a terminated rhombic has 3db of loss in the terminating resistor, both on transmit AND receive. An unterminated rhombic doesn't have this loss, but it is a bi-directional antenna.
     
  15. KA2FIR

    KA2FIR Ham Member QRZ Page

    Is there a record of this?
     

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