Trying to lengthen my 10mtr. end fed to 39 metres in length. To do this I need the first leg (10mtr.) to run at a lower height approx (5mtr)turning back on a dog leg, and the final 29 meters then gaining height to approx. 9 metres high to of Gable end of house. Observing the correct Unun and correct installation which I have already with the 10 meter wire. My question is would the fold back, although climbing in height interfere with radiating correctly.

I can not find anything which suggests its unwise.

Thanks for any input. CHRIS.

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    $\begingroup$ Welcome to hamSE, Chris. I hope we can answer your question. A "stick figure" diagram would be very helpful. $\endgroup$
    – Brian K1LI
    Commented Nov 23, 2020 at 12:03
  • 1
    $\begingroup$ The answer to your question depends on the frequency of interest. Length 10 meters plus 29 meters makes a high-impedance horizontal antenna for wavelength 58 meters with a vertical matching line. For lower frequencies it is a poor but usable top-load variant. Is the antenna meant for reception or also for transmission? $\endgroup$
    – user16925
    Commented Nov 23, 2020 at 22:14
  • $\begingroup$ It was for transmit and receive on lower frequencies ie. 3.550. However, I acknowledge your comments thank you, and now considering simply a 29 mtr. end fed wire in a vertical > shape. (one above the other > ) The feed end at the lower end. approx. 4.8 mtr. high. With the height rising to 7 mtr. Your thoughts would be appreciated. $\endgroup$ Commented Nov 25, 2020 at 8:29
  • $\begingroup$ That is important information, the frequency and TX/RX-use. The half-wave antenne, the horizontal part, is ok for skywave. The vertical part is connected to a high-impedance feedpoint and the current in the vertical part is low. This L-shape CAN have the advantage that the matching in this vertical bended line causes a higher-than-50 Ohm base point impedance. Then efficiency is higher (lower loss in earth system) and matching to 50 Ohm requires a tuner. Low angle radiation is poor; skywave is good. $\endgroup$
    – user16925
    Commented Nov 25, 2020 at 11:05


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