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hanging a vertical 2m antenna

Discussion in 'General Technical Questions and Answers' started by W4EAE, Dec 4, 2018.

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  1. WE4E

    WE4E Premium Subscriber QRZ Page

    You don't have to hang it from the top. Attach your paracord or other non-conductive support line to the bottom of the antenna, and use zip ties or some other method of tagging off the vertical portion to keep it upright. That way, the weight of the antenna is borne by the bottom like it's intended to be.
     
  2. KA0GKT

    KA0GKT Ham Member QRZ Page

    For three years, I had a hanging sleeve dipole for 2-meters hung under the ice shield over a mountaintop FM / TV transmitter building. I soldered a 3/8" ring terminal to the end of the antenna making it easier to attach the paracord.
     
  3. W4EAE

    W4EAE Ham Member QRZ Page

    I am sorry, I was thinking of a different 10' antenna made by Diamond. The F23H looks like the ticket.

    If I just fly this with a pipe hitch, will it be able to handle it's own weight? I am planning to runing a separate line to support the coax, and to stabilize the antenna (as much as possible being in a tree).
     
  4. W4EAE

    W4EAE Ham Member QRZ Page

    Thank you. This sounds sturdy, and would be quite simple.
     
  5. N2UHC

    N2UHC Ham Member QRZ Page

    I've hoisted a J-pole up into a tree while camping before. Worked pretty well especially since we were at a campsite located on a bluff. Now, for camping, I have a portable antenna mast I take along and mount a Slim Jim on top of it.
     
    K3XR likes this.
  6. KC3SWL

    KC3SWL XML Subscriber QRZ Page

    I have a similar installation at my QTH. My tower is a pine tree that goes up about 60 feet or so give or take a few. I use the MFJ 1750 5\8 wave ground plane with a rope tied around the mounting plate then going straight up with part of the vertical radiator taped or zip tied to the rope going up to the branch. The antenna remains upright and the four radials are not slamming into anything as the top of the vertical element is just below the tree branch.. It works for me since I get repeaters on my Kenwood TM2550 up to 40 miles away.The LMR is a great choice as it has low loss for those pesky VHF signal runs outside the shack. If the Diamonds or Comets are too big and you have to remember if it ices up that's a lot of weight hanging off that branch then you might want to take a look at the 5\8 wave ground planes. They are light weight but do have a bit of gain above the average vertical. I found that out tuning the antenna about 4 feet off the ground with my Alinco DJ500 dualband handheld and a handheld SWR meter and hitting the repeater 30 miles away .
     
  7. AF7TS

    AF7TS Ham Member QRZ Page

    I have not tried this, so just an idea to consider: If you use WE4E's approach of supporting the weight from the bottom and using ties above to keep the antenna upright, could the top of the antenna be above the anchor point in the tree?

    73
    Jon
    AF7TS
     
  8. KC8VWM

    KC8VWM Moderator Volunteer Moderator QRZ Page

    Slim Jim inside 1" PVC tubing...

    IMAG0426_zpsrfbhoqvz.jpg
     
  9. AA7EJ

    AA7EJ Ham Member QRZ Page

    I have nothing against experimenting with antennas , actually it is my main interest in amateur radio.

    I also believe that laws of physics are nothing to tamper with.
    In other words "resistance is futile - you will be disappointed with results "if you ignore those laws.

    Here is a layman definition of Slim Jim:

    The Slim Jim is a vertically polarized omnidirectional end-fed antenna having considerable "gain" and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better.

    Then look at your results so far:

    repeaters within 35 miles in all directions
    simplex users with similar height advantages to mine within 25 miles
    repeaters within 85 miles are reliable from north-northeast to west-northwest
    the change in temperature the first couple of hours after sunrise brings me repeaters up to 130 miles NNE to WNW reliably
    My record DX contact during inversion is 258 miles (I've only been doing this a couple of months)

    Then look at your goal:

    My goal is to increase my reliable range, making me less dependent on weather

    Law of physics states that VHF / UHF propagates "in line of sight " and "on occasion" via "ducting " AKA temperature inversion and other weather or physical related phenomena. ( Ever did EME or meteor scatter ?)

    Obviously all outside "reliable" way of propagation.

    Bottom line - that is the way 2 meters propagate.
    Yes , you can experiment to achieve increased range , but I would not expect it to be repeatable at will , hence "reliable".

    Using "unidirectional antenna " would definitively improve your "range" , but hoisting Slim Jim up few feet may amount to "hill of beans".

    72 Shirley





     
  10. KC8VWM

    KC8VWM Moderator Volunteer Moderator QRZ Page

    Sometimes the goal is "cheaply and quickly as possible."
     

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