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My portable Inverted V

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KO4JZK, Feb 23, 2021 at 12:18 AM.

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  1. KO4JZK

    KO4JZK Ham Member QRZ Page

    I can't take credit for building it from scratch, but I picked up a 20M dipole on ebay and added a 1:1 balun underneath - fed with 25' RG-8U Coax. Adjusted ends as best I could to achieve roughly 1.24:1 on most of phone band. Telescoping fiberglass mast. Base is PVC pipe secured guyed with straps. I had the center insulator at 19 ft above ground and the apex angle at 90 degrees.

    I reached Costa Rica and Nova Scotia from coastal South Carolina with 6 watts. I wish I could have had this more in the open but my lot has obstacles.

    I used bungee cord from the end insulators to paracord secured to tent stakes in the ground

    This is a pretty easy set up. First time up took a little time and practice, but it comes down in 5 minutes, really easy. Lightweight and portable. It's good for a few hours, maybe a weekend if you keep an eye on the base and the telescopic sections. I wouldn't leave it out in bad weather.

    I am going to try putting the antenna at 21' or 22' next time; that's about as high as I can go before adding more coax which I don't care to do.

    I would love to hear your thoughts and suggestions about any room for improvement you see. 20M Inverted V.jpg
     
    KK4NSF, VA3QY, AI3V and 2 others like this.
  2. AK5B

    AK5B Ham Member QRZ Page

    Since it appears you are operating portable style fromn your home, why not "go for the gold" and (when you can do so) get a taller mast (maybe a Spiderpole or MaxGain Systems) with the feedpoint around 35 feet (full half wavelength above ground)---you will likely enjoy dx results much more often. The small amount of additional coax required will not affect performance at all.

    73,

    Jeff
     
  3. K2WPM

    K2WPM XML Subscriber QRZ Page

    Hey Jeff
    Congrats on Extra.
    How about using those beautiful antenna hangers.
    Look like 80 foot pines!
     
    AK5B and WB5YUZ like this.
  4. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    Why not? It is the thing that will improve performance the most. There is no substitute for height with horizontal antennas!

    Also, I don't see so good anymore, but it looks like your included angle is dangerously close to 90 degrees. Keep it more obtuse than that, as angles less than 90 degrees lead to cancellation.

    Even so, SC to CR with 6 watts SSB is pretty good!
     
    KK4NSF, AK5B and WA7ARK like this.
  5. VA3QY

    VA3QY Ham Member QRZ Page

    Nothing beats a great portable setup.

    I use my multi-band delta loop - h5anx mk4 version. 20m - fed with 4:1 air core balun from the side - it gives me 5 bands - 20/17/15/12/10. Just mount it to a slotted fibreglass pole of 7m; DX operation from A22 - could get into NA and JA.
     
    KK4NSF and AK5B like this.
  6. AK5B

    AK5B Ham Member QRZ Page

    Just checked your QRZ page and I see you have a great location for DXing---and are interested in checking out the saltwater enhancement available to you. Like you, I live about a mile or so from the sea and when I go portable from the shore with my home-brew two-band elevated vertical I have a blast. Also, it's much quieter out there by the sea (at least QRN and RFI-wise). If you have wind like I do most of the time I can recommend the Heil Pro7 headset---not the lightest or most comfortable headset around but it really shuts out the wind and wave noise very well.

    I will also recommend trying a vertical of any sort to add to your antenna arsenal, especially apt for your location. Saltwater enhancement only happens with vertically polarized antennas and it is always a good idea to have another type of antenna to use and switch back and forth to for checking signal strength anyway.

    Your fiberglass mast would make a great vertical antenna for 10-20 meters easily; just add wires and rig up a sturdy portable mount. I use something similar for my seaside portable ops and cut two 1/4-wave elements for 17 and 20 meters as well as two radials for each band. It's essentially an elevated fan ground plane and works well as long as the two elements are separated from each other a couple-three inches apart. The base is about 6 feet above the seawall where I set it up.

    I slip my pole over a steel dirt tamper picked up at Lowe's and weighted down with rocks or some huge steel bolts I have on hand. Running the radials out to a couple of weighted tripods affixed with 6-foot driveway markers completes my installation. A Bioenno 30 amp-hour (overkill) powers my rig which I like to run about 50-60 watts (SSB only). Here's a couple of pics to better illustrate things:
    IMG_8107QRZ.jpg
    The winds are often so strong that I enlist the support of one of the palms to keep my skyhook vertical. Because of this I plan to add a larger steel or aluminum plate to the bottom of my soil tamper mount (covered with a 6' length of grey PVC pipe in the photo above) so it is more tip-over proof.

    IMG_8035CC.jpg I am fortunate in finding this great spot only 2 miles from my home QTH to chase dx unhindered and in the great outdoors. There's even a polished marble bench where I can sit and enjoy the view while I tune around for weak dx signals.

    I imagine your portable locations are very similar on Hilton Head Island and as such, I guarantee you will have a ton of fun in your quest.

    Congratulations on acquiring Extra class and welcome to the Forum (I think we have six Jeffs here now :D).

    73,

    Texas Jeff
     
  7. KK4NSF

    KK4NSF Ham Member QRZ Page

    yes indeed! It's almost as bad as the number of DAVEs here! We should start assigning numbers to each other. I'll be Dave #1, you can be Jeff #2, and the new Jeff can be Jeff #2.... and so forth. Oh wait! Maybe we can go by our call signs! That might be easier. :p:D
     
    AK5B likes this.
  8. KO4JZK

    KO4JZK Ham Member QRZ Page

    The mast is 31' ft so I can get the antenna up to maybe 26 without stressing the top. I did find a branch at about 35' that I may be able to swing the wire over with weight and some paracord. Maybe another 10' of cable needed if I move my setup to the front of the house. Thanks for your suggestion.
     
    AK5B likes this.
  9. KO4JZK

    KO4JZK Ham Member QRZ Page

    The pines would take a near super human effort to launch a weight over even the lowest branches. I have a nice oak in the front yard which I might put into service for a weekend or two over the summer....a special event tree. If people driving by the house see an antenna out all the time, I will be blamed for every neighborhood cell phone and cable disruption for all eternity.
     
  10. KO4JZK

    KO4JZK Ham Member QRZ Page

    We have a rocky bluff nearby about 20' over the water. Lots of privacy at the end. I will model something after your antenna. I saw a Youtube video of a ham in PA reaching Greece and I think Portugal on 5 watts. I know it is possible. Europe should definitely be in play from the edge of the Atlantic. Thanks!
     
    Last edited: Feb 23, 2021 at 10:24 PM
    AK5B likes this.

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