SOTA outings by KØMOS and contributors

Ultra-lightweight 2m Yagi for SOTA

Written by

in

,
Yagi – Dimensions

I am always carrying my HT (Yaesu VX-7R) as a backup on my SOTA activations. It saved my butt on two occasions when high winds prevented me from setting up my vertical Buddipole. Since high winds are not unusual at higher elevations I was looking for a better antenna compared to the stock rubber-ducky for future activations. I found an antenna I really liked on Youtube, created by David/KD7MNI who was inspired by a design by Paul/KD5IVP. Paul even shared his plans online. I based my own plans on the info provided by David and Paul and after a week-end it was ready to test. A lightweight arrow-shaft houses the piano-wire for elements nicely but I was not happy with the dangling RG-8x… even wrapping it around the arrow-shaft made it awkward to transport… so I never actually took it to a summit until last week, when I activated Mt. Herman (WØC/FR-Ø63) with Steve/wGØAT.

Yagi on Mt. Herman (photo by Steve/wGØAT)

On the summit I had a real problem with my Buddipole coax and had to rely on my 2m 3-element Yagi to be able to claim my points. So… did it work you ask? YES, it sure did… the furthest contact I made was with Ken/WB9QDL who was in Thornton in his car (~60 miles). Not that the distance is unusual for a 2m contact with 5W but we had the opportunity to compare the signal with Steve’s HT. According to Ken, my signal and audio quality was better than Steve’s HT with a 17″ flexible whip antenna.

Remains of a Yagi

Good enough for me. I decided to take the antenna on my double-activation of Lily Mtn. & Panorama Pk. to see what it is capable of. Unfortunately it never came to another test. The antenna was strapped to the outside of my backpack. The light-weight arrow-shaft broke apart during my ascent through the forested area to Lily Mountain without me noticing and I lost some of the piano-wires which were stored inside.

My Conclusion: It seems that the antenna was just too flimsy and not rugged enough for my purpose. Most trails around here start well below the treeline and there is always a part where I have to bush-whack through trees.  The arrow shaft is too long to be stored in a backpack and thus needs to be strapped to the outside. Using another container to protect the antenna seems to defeat the purpose of having an ultra-light antenna. I guess it is time to try a tape-measure antenna next  :)

Video of the antenna in action:
httpvh://www.youtube.com/watch?v=TeTrAPNo8tQ

If you would like to leave questions or comments, please do so through Youtube.

Check my other Yagi-Uda construction attempt.


ATTENTION !! WARNING !! There are old mountaineers, and bold mountaineers… there are no old-bold mountaineers. Hiking and mountain climbing are potentially hazardous activities particularly in Colorado with its extreme elevations. I am not accepting responsibility for any death or injury resulting from activations based on my trip reports. Proper training, experience, and personal capability assessment is required – enjoy!

Comments

21 responses to “Ultra-lightweight 2m Yagi for SOTA”

  1. N2RRAny Avatar

    [..YouTube..] Gotta really hit SOTA hard this year. Nice vid!

  2. N2RRAny Avatar
    N2RRAny

    Gotta really hit SOTA hard this year. Nice vid!

  3. rvisokey Avatar

    [..YouTube..] Nice vid. You should post more about the construction of the yagi since you mention/feature it so prominently.

  4. Richard Visokey Avatar
    Richard Visokey

    Nice vid. You should post more about the construction of the yagi since you
    mention/feature it so prominently.

  5. DL9MDI Avatar

    [..YouTube..] Hello Matt. The antenna looks very interesting. Thanks for the information. 73 de Manfred

  6. DL9MDI Avatar
    DL9MDI

    Hello Matt. The antenna looks very interesting. Thanks for the information.
    73 de Manfred

  7. Wavesfriends11 Avatar

    [..YouTube..] Excellent video it gives ideas to construct a light YAGI for 144Mhz TNX 73’s John 14FDX058

  8. Wavefriends Avatar
    Wavefriends

    Excellent video it gives ideas to construct a light YAGI for 144Mhz TNX
    73’s John 14FDX058

  9. KD8PIQ Avatar

    [..YouTube..] Great view.

  10. KD8PIQ Avatar
    KD8PIQ

    Great view.

  11. k0mos Avatar

    [..YouTube..] References to the construction can be found in the blog post mentioned.

  12. KØMOS Avatar
    KØMOS

    References to the construction can be found in the blog post mentioned.

  13. k0mos Avatar

    [..YouTube..] Hi Fred, it’s certainly lightweight – perfect for your activations in Germany/Austria. Thanks for your comment.

  14. KØMOS Avatar
    KØMOS

    Hi Fred, it’s certainly lightweight – perfect for your activations in
    Germany/Austria. Thanks for your comment.

  15. k0mos Avatar

    [..YouTube..] Looking forward chasing you. Thanks for your comment. 73

  16. KØMOS Avatar
    KØMOS

    Looking forward chasing you. Thanks for your comment. 73

  17. flamedrag18 Avatar
    flamedrag18

    I read your page, sorry to see the arrow shaft couldn’t hold up, but there
    is a solution to making your arrow shaft collapsible, just cut the arrow
    shaft between the holes for the piano wires and add some broadhead inserts
    on every connection and superglue some short # 8×24 all thread for each
    connection on one side and leave the other free. for the wire, just roll it
    up in a coil and use small velcro or just tape to keep it there. piano wire
    will just spring back straight when released.

  18. Carl Gorse Avatar
    Carl Gorse

    Now that looks excellent frm M6HPL

  19. tchesari fsantana Avatar
    tchesari fsantana

    COM UM RADIO DESSE POTENTE E NESSA ALTURA ATE COM UMA CHAVE DE FENDA ELE
    SINTONIZARIA QUALQUER FREQUENCIA.

  20. Warsteiner Deutschland Avatar
    Warsteiner Deutschland

    Deutsch, oder?

  21. Thach Ninhvan Avatar
    Thach Ninhvan

    hi. where are you from? i’m in vietnamese
    write soon

Leave a Reply

Your email address will not be published. Required fields are marked *