14MHz delta at first harmonic, vs. 45cm magloop.

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by MW1CFN, Jun 1, 2021.

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  1. MW1CFN

    MW1CFN Ham Member QRZ Page

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  2. KI8DJ

    KI8DJ Ham Member QRZ Page

    Everything works. Sometimes better than expected.
     
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  3. AF7ON

    AF7ON Ham Member QRZ Page

    I like the configuration of four parallel loops. I assume this reduces resistive losses and makes it look like an electrically fatter loop.

    Mike
    AF7ON
     
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  4. 4X1SO

    4X1SO Ham Member QRZ Page

    Isn't the first harmonic of 14 MHz ---- 14 MHz?
     
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  5. M0AGP

    M0AGP Ham Member QRZ Page

    Interesting- I didn’t know that mag loops are expected to have a big cloud warmer lobe.

    I wonder if you could phase two mag loops, one directly above the other, to get rid of the vertical radiation lobe?

    This is a trick used when stacking beams...
     
  6. AK5B

    AK5B Ham Member QRZ Page

    The nice thing about STLs is that they "spray" a half-donut pattern of RF at every angle between the horizon and the azimuth, fulfilling every user's dream (be it NVIS for the low bands, local, regional or dx)---even at low heights above ground. The nulls are broadside to the doughnut and can be useful for nulling QRM or QRN.

    73,

    Jeff

    The Loopy Guy in South Texas
     
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  7. M0AGP

    M0AGP Ham Member QRZ Page

    Ah this does make sense yes. So maybe you can make a better DX antenna by stacking them vertically and setting up the spacing and phase to put more of the radiation at the horizon and less at the azimuth? I haven’t seen analysis of this before. I wonder how you would represent a mag loop in EZNEC? Literally as a loop much smaller than a wavelength?

    I wonder if you could make a parasitic array? I guess it would be a mini-quad. Probably would need computer control to set the resonant frequencies of the parasitic elements, using a pre-made table...

    Though not rotatable (much) you could imagine such a thing as an apartment antenna. On 20m the 2 element version wouldn’t have a very long boom...
     
  8. AK5B

    AK5B Ham Member QRZ Page

    I've heard of placing an identical STL parallel to another a few feet away to effect some gain but I've never tried it---makes sense, though. (I think AF7ON mentioned this in another loop thread couple-few years ago)

    Stacking might be another way to accomplish squashing the pattern that but the logistics of doing so would seem a bit on the nightmarish side to me. Perhaps if one had a big wooden deck that was a decent height above the ground...

    Food for thought, Mike!

    73,

    The Loopy Guy...
     
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  9. MW1CFN

    MW1CFN Ham Member QRZ Page

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  10. AK5B

    AK5B Ham Member QRZ Page


    Yeah! Automatic 6db gain right there! I've bean meaning for years to try my loops over at the bay here and the only thing I can say is procrastination always gets the better of me---I have no excuse!:oops::D

    I'm getting ready to go on a long trip but when I get back in mid-July I must finally get around to trying this---would be great if we could have a loop-to-loop qso while operating portable by the sea.

    Here's my main portable QTH (2.9 miles from my house):
    IMG_8005CC.jpg Had a 59/59 20 meter QSO with a chap in Scotland from here using my 17/20 fan vertical last summer---it's a clear shot over to UK and many other places, too.

    Anyroad, your portable loop photo is another inspiration and good reminder for me to get active with my loops next to the liquid copper that lives between us---I promise to try this when I get back home about a month and a half from now...maybe we can set up a sked at that time, too.;)

    Cheers,


    Jeff
     
    Last edited: Jun 3, 2021
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