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I'm thinking about putting together an Echolink link node on my local repeater frequency so I can participate in the weekly net when out of town. This seems straightforward as it's simply:

Being in an HOA, I have to try and keep my house from looking like an antenna farm / porcupine, so I thought "why not a panel antenna?" I figure I can build the elements out of 10AWG solid wire and place it on a vertical surface outside my house, paint it with leftover house paint, and it should be nicely unobtrusive.

Is there a reason not to build a biquad for such a purpose? Is there a better (less observable, easier to build, ...?) antenna for connecting from one known point to another?

I considered a simple dipole, but there's no good way to mount it and I have rain gutters on the side of the house that faces the repeater. A biquad, being relatively flat and vaguely directional, seems like an ideal solution to this particular task.

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  • $\begingroup$ I am assuming that the repeater is not your personal property -- given that, have you checked to see if someone else has not already provided a link for your local repeater. I have actually used Echolink once years ago so my comment may not be fitting to your question. $\endgroup$
    – K7PEH
    Commented Sep 7, 2017 at 3:09
  • $\begingroup$ @K7PEH - The repeater used to be on Echolink directly, but isn't since we switched to a new repeater controller that doesn't support it. When it was on Echolink, it had horrible AC hum. $\endgroup$
    – William
    Commented Sep 7, 2017 at 4:29

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Why not indeed. A biquad sounds like a fine solution, with the only caveat that on 2 meters (145 MHz) it will be significantly larger than the 2.4 GHz constructions typically seen. The size of the panel is on the order of one wavelength, so you're looking at something approximately 2 meters square. At that size you may want to construct the panel from a cage of wires, as a 4 square meter sheet of copper will be a little expensive.

The other difficulty is mounting the antenna high. Due to line-of-sight propagation on VHF, once the antenna is beyond the radio horizon, path losses increase sharply. This is because you must now rely on scattering off other objects to get your signal across.

So, given the option of mounting a panel antenna down low on the side of the house, and mounting a smaller antenna up high, I'd opt for the latter.

For example, HTs often come with compact antennas which are smaller than the 1/4 wavelength that would be required of a resonant monopole. Such an antenna, say mounted on your gutters for a ground plane, and painted to match your roof, may be sufficiently small that it will go unnoticed.

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  • $\begingroup$ The size of the reflector is a valid point. I must have somehow misread the diagram (goo.gl/fV1WCV) because you're right that a six-by-six square on the side of my house isn't going to unobtrusive no matter what color it's painted. As for cost, I was going to use spray adhesive to bond aluminum foil to a thin piece of plywood. I'd read that biquads aren't particularly sensitive to the size of the reflector and since it's a parasitic element, it seemed like the resistive losses due to aluminum's lower conductivity would be minimal. Does that at least sound sensible? $\endgroup$
    – William
    Commented Sep 8, 2017 at 19:35
  • $\begingroup$ And thanks! I'll have to get better at, uh, reading. $\endgroup$
    – William
    Commented Sep 8, 2017 at 19:40
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    $\begingroup$ @William-Rem Well, being a parasitic element doesn't make the losses any less relevant, but aluminium is still a good conductor, and given that it's a whole sheet rather than a thin wire of aluminium, the current density will be low so conductivity matters less. $\endgroup$
    – Phil Frost - W8II
    Commented Sep 9, 2017 at 12:23
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How about a 2- or 3-element Yagi or cubical quad? A 2-element quad would be only 1 meter (or less) square on the ends, and likely even shorter on the sides between the driven element and reflector.

You could even make the enclosure look like (or be!) a birdhouse.

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    $\begingroup$ Or a Moxon! I might be able to stick one of these on the trim of our chimney, which is wood. $\endgroup$
    – William
    Commented Sep 9, 2017 at 0:30
  • $\begingroup$ Hah. Only you would come up with a birdhouse solution, @Mike. I like it. The first thing that comes to mind is that is might actually attract birds. I wonder how that would affect the antenna tuning? $\endgroup$
    – SDsolar
    Commented Sep 10, 2017 at 2:59
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There are literally hundreds of antenna designs you could use. There are many variables to think about. The "best" answer probably depends heavily on what you (and the HOA) will tolerate. The Moxon you mentioned would be great, if allowed. If you need a smaller, less visible antenna then placing it as high as possible would help. You may be able to make a simple vertical dipole slightly below the top of the chimney with a reflector attached directly to the chimney and the driven element in front of it. This would be 2 elements and much less visible. Some designs need only .15 wave spacing between the 2 elements. This would give some gain and directivity to it. If made of thin wire it might be hard to see. You might even get away with calling it a "TV" antenna. If a TV antenna is acceptable then a Moxon, Hybrid Moxon, Yagi, or Quagi would probably be excellent.

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