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My Lightning 6 Quad antenna

Discussion in 'Amateur Radio Antennas' started by Drifter, Sep 23, 2009.

  1. Marconi

    Marconi
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    Usually if I can hear em' I can talk to em'.

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    When my matcher idea started working for the model I had the idea that the SWR bandwidth scans looked somewhat similar to what you reported. Albeit the heights were different I was also impressed.

    Thank you for all your help with the dimensions.


    When I started modeling the physical matching networks the only data I had to compare my results was if I could get the bandwidth near to what the manufacture reported. Then, if the BW was similar...I felt like the model might be close to correct.

    The tap point locations also seem similar to what you report. However, I did a Free Space model on the vertical model and had to readjust the tap point to get the Average Gain results to improve. I'm not happy with the AG value of 1.053 but I did not fiddle with the segments either. I may be able to get it better with a little tweaking of the segments.



    Dennis, I had a thought that maybe LA looked at something different in their bandwidth report too, but a lot was going on and I forgot about the question.

    My eyes are bad and I have trouble with little details and you were back a little for from the screen for me. I could not tell what you were focusing on in the video. I'll check it our again.

    Below is the set of models for the Vertical side of your L4+. All I did was setup the antenna to your specs as best I could. I also added my idea for the physical matching device used for this antenna.

    1. is in Free Space
    2. is at 36' feet
    3. is at 10' feet

    Below is the setups for the Vertical side of you L4+.
    1. is in Free Space
    2. is at 36' feet
    3. is at 10' feet

    I also changed the title name to "L4+Vw-match 28.7mhz FS" and at 36' and 10' feet.
     

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    #121 Marconi, Apr 21, 2017
    Last edited: Apr 22, 2017

  2. dennis4040

    dennis4040
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    What do you think overall?
    The gain is about what I expected, the front to back is not great but that is not to critical for me.
    What is this spec? AG value of 1.053
     
  3. dennis4040

    dennis4040
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    I found this so I understand a little bit of what u are talking about.

    "Folks who have studied this issue suggest that a valid range for the Average Gain is 0.95 through 1.05. Beyond that range, confidence in the results starts to drop."

    Considering the complexity of the dual polarity feed I think it looks pretty good overall but I have never done any modeling.
     
  4. dennis4040

    dennis4040
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    I have raised the L4+ to about 12' to the boom.
    SWR and resonance is very similar on vertical and horizontal.
     

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