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Homebrew, Homebrew, Homebrew.

Discussion in 'Homebrew and Kit Projects' started by KC9AEI, Apr 21, 2012.

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  1. KC9AEI

    KC9AEI Ham Member QRZ Page

    Well, my ham shack is nearly finished and operational. I've got a mix of new and used equipment, which is mainly my IC-706MIIG which I bought from W9MAG. NOW, onto my next project. I am wanting to build a homebrew antenna project. I thought of a wire dipole which I could use on all 160m - 6m. I'm sure I can use a 100' homemade dipole made from chicken wire and a balun and use an antenna tuner to tune my way across the amateur spectrum (if this is possible). My other possibility, using a 2 element beam with a tuner and using that across the amateur spectrum. I am basically trying to keep it simple as a good little antenna system to use during field day. I plan on sitting on a picnic bench at my parent's cabin and hunting for my contacts. Anybody have a practical design for this? Thanks and 73!!
  2. KG4NEL

    KG4NEL Ham Member QRZ Page

    Worth reading... wire antennaes.pdf :)

    My vote would be an 80 meter dipole center-fed with ladder line or 300 ohm twinlead. I wouldn't worry too much about 160 meters for Field Day, unless you can get a wire up a decent fraction of a half-wavelength. The station I've operated at for the past decade has never put a station on Top Band, and we've done fairly well for our class.

    The problem with using a 2 element beam for multiband use without being designed for it is that your pattern will get very distorted - you might have nulls where you think you have gain, even if the tuner makes the SWR happy for the radio. It'd be basically impossible to predict the results without modeling it. The 80 meter dipole used on higher bands has nulls, too, but it's a much better-modeled option ;)
  3. AD6KA

    AD6KA Ham Member QRZ Page

    Hi Kevin:

    A 100' coax fed dipole that covers 160m to 6m is going to be a tough pull
    and require a wide range tuner, and be very lossy.

    If you have 132' of space, a center fed dipole using twin lead or
    window line would make a very decent multi band antenna for 80-10m.
    (Your tuner will need a built in balun, or you can use a short length of
    coax to a balun, then connect to the twin lead/ladderline.)
    And you may even be able to tie the ends together (at the tuner)
    and use it as a Marconi on 160m.
    Remember there's no such thing as a free lunch. And the more bands
    you try to get an antenna to work on, the larger the compromises in
    performance you'll run into.

    I also suggest you consider:
    1) Getting a copy of the ARRL Antenna Book (any copy, any year, used or new)
    and look at some of those designs.
    2) Also, I wouldn't chose chicken wire. Will it work? Yes, but I'd still
    use regular copper wire or copper clad wire. (Copper outer coating clad to steel wire) instead, for long antenna runs. Doesn't stretch. Again, it depends on which antenna design you chose, as does whether you need a balun or not, too.
    3) Start thinking on what you are going to use to support the center
    and ends of your antenna. Of course the higher and in the clear the better,
    but wire antennas can be run through trees with little if any loss.

    Well, I don't "do" Field Day, but I do like to operate portable
    while camping in the woods or the desert. Several antennas I like
    for this kind of operating are:
    1) A coax fed "Fan Dipole" for 20-15-10m.
    2) A 40m dipole fed with twin lead, and using a tuner with a built in balun.
    Works on all bands 40m to 10m.
    3) When I am feeling REALLY lazy, a long wire shot with
    a slingshot or bow as high and far up into the trees as I can
    get. (Or my crossbow friend can get). Attached to tuner with
    1/4 wave radials hooked to the ground lug for the bands we want
    to play on.

    Respectfully, you might consider reading up on what exactly
    antenna tuners do and do NOT do.

    Hope this helps.
    Good luck on your antenna project!
    73, Ken AD6KA
  4. KV6O

    KV6O Premium Subscriber QRZ Page

    And I thought this was a thread about homebrew beer. Rats.

  5. KC9AEI

    KC9AEI Ham Member QRZ Page

    I like your ideology Steve. And it would fit underneath this section too as brewing beer can get technical. :D Ken, Thank you for the information on that. I really do need a better understanding of how tuners work with antenna systems. I'm still very very green at this. I've been getting a lot of great help though. And being on the HF side instead of VHF and UHF. Honestly, I didn't know how much use 160m got. I was looking to run a competition rig without a bunch of antenna's, and everything else. Right now at home, I put up an Alpha Delta DX-CC antenna which seems to do well. I was thinking of HF vertical, but for the different bands I want to play on, I would need a 40 ft antenna. And thought that would be an eye sore in my back yard. BUT, I'll get to where I want my system to be at eventually. The intention was to just unplug the IC-706 from the house and use it in the field too. That was the plan.
  6. AB9LZ

    AB9LZ Ham Member QRZ Page

    A good antenna to consider for semi portable operations is the center loaded vertical, they are easy to make using hardware store aluminum rod (buy a tap as well so you can join various lengths with coupling nuts). A collapsible whip, and I believe the loading coil can be bought from MFJ, or better yet make your own by winding the coils over from PVC tubing. Google it, there are lots of examples but Phils (AD5X) article is a good place to start.

    The nice thing about this type of antenna, is that you don't need to depend on having a good tree nearby (or are operating in a treeless area, like the beach), nor deal with the hassle of trying to send a wire over the thing. Plus, they can be very fast to setup and take down, mine goes up in under three minutes. Various traps, moveable taps, or even a screwdriver loading coil, used in conjunction with the variable lengths of rod, will easily cover 40 thru 6 meters with reasonable, to very good performance.

    73 m/4
  7. KD8DEY

    KD8DEY Subscriber QRZ Page

    Do you have access to 1420 feet of barbed wire??
    From what I have heard, That makes for one heck of an antenna.
    Dunno if it was end fed, center fed, or Marconi style though.
  8. KB5HAB

    KB5HAB Ham Member QRZ Page

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