45 degree angle for this antenna

Discussion in 'VHF/UHF - 50Mhz and Beyond' started by TA3AIK, Jun 20, 2017.

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  1. TA3AIK

    TA3AIK Ham Member QRZ Page

    Hi everyone ;

    First of all, i hope that here is the right place for this topic. This 2 meter antenna have been made by my ham radio friend that his callsign is TA3TS. He is curious about that if we angle 45 degree to of this antenna radials at that time would it make a difference about quality of TX and RX positively or negatively ? İs there anyone who have an idea about that topic ? All kind comment and help would be appreciated.

    Thanks for in advance
    TA3AIK İsmet
    algon1.jpg 20170221_132157.jpg
     
  2. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    May be different there, but in the U.S. and also Canada (and I think western Europe), all "FM and repeater" VHF work is vertically polarized, and all "weak signal" VHF work (CW-SSB-digital) is horizontally polarized, and there are good reasons for all of that.

    Here, if the goal is to work FM, I'd stick with purely vertical. If the goal is to work the weak signal modes, I'd stick with purely horizontal. To cover "both," I've used circular polarization many times; that seems to be only about 3 dB "down" from the "correct" polarity and works pretty well but you can't do that with a ground plane type antenna.
     
  3. TA3AIK

    TA3AIK Ham Member QRZ Page

    ----------------------------------------------------------------------------------------------------------------------------------------
    Thanks for your comment. It is excessively appreciated. But i did not mean the polarization of whole antenna. If we just angle 45 degree to radials at that time would it make a difference ? What do you say about that ? ( i meant for only FM works ) Thanks again..
     
  4. KL7AJ

    KL7AJ Premium Subscriber QRZ Page

    Hi there!
    If you angle the radials downward, you will raise the feedpoint impedance. It might give you a slightly better impedance match but it won't help your radiation pattern much. I suspect your antenna is just fine as it is.
     
  5. TA3AIK

    TA3AIK Ham Member QRZ Page

    Hi, thank you so much for your comment. It is really helped to my questions in my mind. By the way, the antenna is working really great.
     
  6. KG7SWP

    KG7SWP Ham Member QRZ Page

    THeoretically, your antenna, as it is should be about 35 ohms. If you do 45* radials, it should be closer to 50 ohms.
    Have you checked the SWR or resonance?

    Ed
     
  7. KL7AJ

    KL7AJ Premium Subscriber QRZ Page

    As we always say here in America, "If it ain't broke, don't fix it." I don't know how to translate that to Turkish. HI!
     
  8. TA3AIK

    TA3AIK Ham Member QRZ Page

    "If it ain't broke, don't fix it." This is exactly meaning that ''Bozuk değilse kurcalama'' :D thanks again.
     
  9. TA3AIK

    TA3AIK Ham Member QRZ Page

    Hi Ed ;
    First of all, thanks for your comment. In fact, of the antenna brand is Algon. This antenna is that on the scrap heap from formal government structure. The SWR is 1.1 and resonance 48 ohms at the moment. Normally, it is working without any radials which is my friend have added them. He said that, the RX incredibly raised with them. This is the story.

    TA3AIK İsmet
     
  10. KG7SWP

    KG7SWP Ham Member QRZ Page

    If you got 48 ohms with no reactance at the desired frequency, leave it as is.

    Ed
     

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