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50 mhz polarization

Discussion in 'VHF/UHF - 50Mhz and Beyond' started by VE3EKJ, Nov 24, 2020.

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  1. VE3EKJ

    VE3EKJ Ham Member QRZ Page

    I've been scrounging some 6 metre gear and have to make a decision about an antenna.

    I don't really care much about local. I've seen all the traditional lore about vertical polarization for local and horizontal for DX but I can't help but wonder if for sporadic E does it really make much difference?

    A vertical groundplane would be easier to build for me. I always thought that propagation skip scrambled polarization anyway.

    Anybody got any thoughts to share? I've got a few months before I have to commit. I am a Canadian after all and it will be too cold for outside work for some months.

    Bill VE3EKJ
     
  2. KD0CAC

    KD0CAC Ham Member QRZ Page

    I think the need is for both .

    The vertical gives 360 deg. reception and a beam gives more power in a beamed direction and also can cut out unwanted signals .
    So using both together - Rx & Tx antennas .
    And last be able to see & use witch one works best on a individual basis .

    The beginning of an antenna farm ;)
     
  3. AA4PB

    AA4PB Ham Member QRZ Page

    If you are running SSB, CW, or digital on 6M then you definitely want horizontal polarization. A Yagi will give you gain in the desired direction and minimize noise arriving from other directions but it requires a rotor. If you can't do a rotor or if you want a secondary omni-directional antenna then use a horizontal loop. I run a 5 el Yagi at 60 feet on 6M and don't have any problems with missing stations because they are in a direction other than where the Yagi is pointed. Very often stations (even DX) can be heard off the back or side of the antenna strong enough to know that they are there. You also get plenty of clues about what direction the DX is in by copying other stations who are working them. I don't find a need to have an omni-directional receive antenna. If the power lines are making noise on a windy day, I find an S9 noise level when pointed at them and S zero when they are off the side of the Yagi so the Yagi is a real plus in that situation.
     
  4. WA4SIX

    WA4SIX Ham Member QRZ Page

    The Cushcraft 3 or 5 element yagi can be turned by a cheap TV antenna rotator. Get one. It's well worth it.

    Ed
     
  5. K3RW

    K3RW Premium Subscriber QRZ Page

    A dipole doesn't disappoint on 6m, its like a 1el beam! However, I highly suggest a Moxon. Easy to build, feed, 50ohms typically, and light. I built mine on PVC. Got 4 elbows and two pipes and ran wire around it.

    I've worked 6m vertically polarized many times on SSB and digital. It works, but cross-polarity losses can be super high. FM on 6m is typically vertically polarized but so few are on 6m simplex.

    Some compensate by tilting a yagi 45deg for the best of both worlds on 2m, and that wpuld work on 6m too, if the FM potential is there. Otherwise stay horizontal.
     
  6. WA2CWA

    WA2CWA Ham Member QRZ Page

    Build a 6 meter turnstile antenna, and at the mid point of each element, bend it 90 degrees straight up. Now you have a 360 degree horizontal and vertical 6 meter antenna.
     
    W0GSQ likes this.
  7. WA3GWK

    WA3GWK XML Subscriber QRZ Page

    Polarization won't matter much for sporadic E propagation. It will for tropo. You will benefit from the gain of a yagi or moxon but when 6 meters is open good, you can make contacts with a dipole or ground plane. You need to decide if you need the extra gain of a beam and whether you want to work local/tropo. My preference for my small lot here is a horizontal moxon,
     
    W5TRL and N4THC like this.
  8. W2EV

    W2EV Ham Member QRZ Page

    Dave (WA3GWK) is correct. 100%. If you wish to truly "milk the aether" for every possible signal, install TWO antennas. A vertical and a horizontal. Install an A/B switch.

    The reason is simple, and scientific: polarization is preserved ONLY on line-of-site pathways. Whenever a wave interacts with either a metallic object (such as a building, presumably with conductive metals in its structure) or a dielectric (everything else), polarization can no longer be predicted reliably.

    To add to the "wonder of RF" -- and if your interest is truly "only DX" -- then it also helps to know that the vertical radiation angle nulls-and-peaks of a vertical antenna and a horizontal antenna at the same height are opposite. The vertical's "peaks" are at the same degrees-of-elevation as the horizontals "valley's". So...if you really want to get specific, you need 4 antennas. H+V at one height and H+V at another height. And...of course, an ABCD switch. Lol.

    HOWEVER...don't succumb to "analysis paralysis". Start with a horizontal (so you can work the locals, too). Something simple like a halo at the top of your pole/tower will provide you with 360-degree coverage without a rotator (I have 4 stacked on my tower). Add a vertical at the same height and A/B them if you want to actually experience what I describe above. Upgrade to a beam if/when you are ready.

    Welcome to one of the coolest hobbies in the known universe. :)

    Ev, W2EV
     
    WA3GWK likes this.
  9. KR4BD

    KR4BD Ham Member QRZ Page

    I have used the Cushcraft AR-6 Ringo (vertical) for over 30 years. Early on, I also had their 3-element beam, but was not happy with its overall performance. I can’t explain it, but the vertical often gave me better signal strengths than the beam. For example, one day I was hearing an SSB station in Ecuador on my beam, but could not peak the signal for good copy, no matter how I rotated the beam. I tried switching to my vertical and BAM...a 59 signal! Both antennas were about 25 feet high. Changing the coax and connectors on my beam did NOT improve its performance.

    I can’t explain it, but I’ve been using ONLY a vertical for all my 6-meter operating for at least 20 years.

    BOTTOM LINE: I have 408 grids, 48 states and 31 countries (mostly SSB and FT-8) confirmed with my 30+ year old AR-6 vertical.

    Please realize YMMV! But if your space is limited, I would certainly include a vertical in your 6-meter plans. DX signals often don’t care how they are polarized!
     
  10. AA4PB

    AA4PB Ham Member QRZ Page

    Years ago I had a Cushcraft AR-6 vertical on top of the tower at 60 foot. I also had a WARC band dipole at 40 feet. Consistently my received 6M signals were stronger on the WARC dipole (that is not even resonant on 6M) than it was with the vertical AR-6. If an AR6 is consistently outperforming a 3 el beam on 6M then I'd say you have a problem with the beam.
     
    ND6M likes this.

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