Antenna wire thru stucco

Discussion in 'Technical' started by KF7JAF, Jun 5, 2014.

  1. KF7JAF

    KF7JAF Member

    I've got my shack in a spare bedroom, and the antenna needs to come thru the wall. Here in the Wild West they build houses out of styrofoam insulation covered in chicken wire and then stucco over that. How big of a hole do you think I need to feed an endfed wire and/or open wire feeders thru the stucco wall? I'm looking for suggestions and ideas regarding this. It has to be XYL friendly as well :biggrin:
    tnx,

    DaveL
    KF7JAF
     
  2. WD5JKO

    WD5JKO Member

    Davel,

    I am not familiar with that kind of construction, but it sounds like making a hole in it wouldn't be too hard. One or two pieces of PVC pipe made flush with the walls would do. Perhaps use a long drill bit to make a pilot hole all the way through the wall, then with a wood bit drill in from each side till the "tunnels' meet. Use the smallest pipe diameter that will still do the job. Seal the ends with caulk, and paint. Once the wire(s) are in place, seal the holes with RTV.

    If this does not pass the test, try an MFJ 4600 series panel that uses a partially opened window. The window can be secured and sealed like with a window AC unit.

    MFJ-4600.png

    http://www.mfjenterprises.com/Product.php?productid=MFJ-4600

    If bringing in OWL from the outside, have some sort of static protection, and arc path to ground. Could also use banana jacks / plugs to disconnect the OWL from the outside, and ground them.

    Jim
    Wd5JKO
     
  3. W5HRO

    W5HRO Administrator

    Actually that foam insulation between the walls is better than the old conventional type and it provides a much better air tight seal. They spray it in there before nailing up the sheet rock and it expands filling in the whole area. If you watch those home improvement shows today like Holmes on Homes for example that's what they use.

    The only thing to watch out for would be the stucco mesh wire (chicken wire). Make sure its not shorting out or being inductively coupled to your wire feeder(s). That could be a problem is you are not using coax. I actually like Jim's suggestion better. The window unit would probably be the best option. Either that or just get a piece of replacement glass made for the window with two holes for feed-thru insulators. I've seen people do that before, but with today's dual pane windows it might be harder.
     
  4. W5HRO

    W5HRO Administrator

    You know, you could also just make one of those window units out of a piece of wood then paint it to match the window. Just mount a couple of feed-thru insulators on it. You could cut the wood to fit the window perfectly. No need for any fancy piece of Mighty Fine Junk.

    This is all provided that your spare bedroom does have a window though :confused:
     
  5. KF7JAF

    KF7JAF Member

    The plywood/plexiglass thingy in the window would work except that the window is open in the summer for the swamp cooler. I'll probly use a hole saw and cut through the outside, plug the hole with a plywood disk, run a feedthru in the disk and do the same on the inside. I was mostly concerned about arkensparken to the chicken wire if it was too close to the antenna wire, especially using an endfed halfwave or similar.
    Thanks for your ideas,

    Dave