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Thread: best antenna

  1. #1161
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    Quote Originally Posted by charan View Post
    yes; till then ill use 7 elements wit 1/4 shorted top
    Charan,
    My apologies for the time this is all taking, but by the end of next week I should have some tested results for the baluns, I finally understood how and why they work, now I just need to make, test and photograph them and the rest of the antennae.
    Ben.
    FR24 F-EGLF1, Blitzortung station 878, OGN Aldersht2, PilotAware PWAldersht, PlanePlotter M7.

  2. #1162
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    yet more technical obsession! lol a coco is an unbalanced antenna, and as the feeder is Also unbalanced... You don't need a BALUN - which is a joining of two words, balanced and unbalanced.
    Impedance transformers may be what you are looking for... But again this is getting overcomplicated, and I'd suggest all this faffery is introducing more losses than the problem you are trying to solve.

    Sent using Tapatalk from my ZX81

  3. #1163
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    Quote Originally Posted by Rooster View Post
    yet more technical obsession! lol a coco is an unbalanced antenna, and as the feeder is Also unbalanced... You don't need a BALUN - which is a joining of two words, balanced and unbalanced.
    Impedance transformers may be what you are looking for... But again this is getting overcomplicated, and I'd suggest all this faffery is introducing more losses than the problem you are trying to solve.

    Sent using Tapatalk from my ZX81
    If they are not as you suggest needed, then why do the commercial ones have them, you cannot just connect a CoCo to a random length of coax and expect it to perform at its best without them as I have discovered.
    Also some of us ENJOY the technical challenges, if you are happy with what you have got then good for you, some of us like to tinker, it keeps the grey matter from turning to mush...
    Ben. (Obsessed and proud of it!)

    NB according to the Antenna handbook (5th edition) a balun IS an impedance transformer.
    Last edited by F-EGLF1; 2014-05-22 at 17:06. Reason: Added note
    FR24 F-EGLF1, Blitzortung station 878, OGN Aldersht2, PilotAware PWAldersht, PlanePlotter M7.

  4. #1164
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    Quote Originally Posted by F-EGLF1 View Post
    Charan,
    My apologies for the time this is all taking, but by the end of next week I should have some tested results for the baluns, I finally understood how and why they work, now I just need to make, test and photograph them and the rest of the antennae.
    Ben.
    Hello Ben; no problem at all take your time. i hope you will get the best results
    RTL SDR : T-VEVZ1

  5. #1165
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    the posts for making a strait forward aerial will come, I just have to find the time to put together something worth posting.

    and to be fair this thread has turned a little advanced learning channel, I've only just had my eye's open to the world of aerials and its all very fascinating.
    T-EGLF8

  6. #1166
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    Quote Originally Posted by F-EGLF1 View Post
    .....(5+1.5 is 6.5 in the UK).....
    Ben.
    But in Canada 5+1.5=7.5 if the person making calculations did not have good sleep last night

  7. #1167
    Purser Rooster's Avatar
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    Arrrr, the wonders of alcohol ;-) lol

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  8. #1168
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    Quote Originally Posted by Rooster View Post
    Arrrr, the wonders of alcohol ;-) lol

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    lol

  9. #1169
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  10. #1170
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    Quote Originally Posted by Rooster View Post
    yet more technical obsession! lol a coco is an unbalanced antenna, and as the feeder is Also unbalanced... You don't need a BALUN - which is a joining of two words, balanced and unbalanced.
    Impedance transformers may be what you are looking for... But again this is getting overcomplicated, and I'd suggest all this faffery is introducing more losses than the problem you are trying to solve.

    Sent using Tapatalk from my ZX81
    CoCo is a balanced antenna. It is a dipole, two equal legs, physically merged, but electrically separate. Since it is end fed, it gives an impression of a whip antenna which is a mono-pole and hence is unbalanced.

    Example: 8-element coco.
    Leg 1: Radiating part comprises of shields of odd elements (1, 3, 5, & 7), phasing part comprises of central wire of even elements (2, 4, 6, & 8)
    Leg 2: Radiating part comprises of shields of even elements (2, 4, 6, & 8), phasing part comprises of central wire of odd elements (1, 3, 5, & 7).

    Please see sketch below.



    .
    Last edited by abcd567; 2014-05-23 at 07:42.

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