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We moved into a new house, and I noticed these wires sticking up for some sort of tent thing for shade. enter image description here

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•I tested the wires to the 3rd prong in the outlet, and it showed a DC dead short to ground.

•The wires are a DC short to each other

I am new to antennas for HF, and my first antenna will be a dipole.

Could I use these to my advantage, maybe as a ground plane over the dipole, or even trying to make it a vertical with the wires as a ground plane?

Or is it just rubbish, and should I try to keep my dipole as far away from them as possible. I know the AM towers have to be very careful by insulating all of the sections of their guy wires from each other.

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I am new to antennas for HF, and my first antenna will be a dipole.

The wires look pretty big, so unless you can place your antenna a couple wavelengths away from them, they are going to couple to your antenna in some significant way. The farther away you can place your antenna (relative to wavelength), the less coupling. You might also be able to significantly reduce the coupling by orienting the dipole to be orthogonal (not parallel) to the direction of the wires.

That the dipole couples with the wires isn't horrible in itself. For example, a Yagi-Uda array utilizes parasitic coupling between wires to great advantage. Your wires probably aren't so carefully placed, so it's hard to say exactly what the outcome will be. You probably won't get an awesome beam antenna, but to the extent that the wires don't introduce additional loss, the RF energy will be radiated somehow, anyway.

The first consequence you will probably notice is that the feedpoint impedance isn't anything like what you'd expect from a dipole. This isn't an insurmountable problem; you just might need some kind of matching network at the feedpoint to get a good match to your feedline.

If you can't avoid interaction with the wires, then you might as well consider using one of them as an antenna. Just about anything works as an antenna if you can get it to match the feedline reasonably well. People have used rain gutters, for example.

I suspect your challenge in making these wires act as a good antenna will be isolating it from the lossy ground. You will have many of the same challenges faced with end-fed antennas. Keep in mind also that the connection to ground for these things may involve some part of your home's wiring, and you probably want to keep RF out of there to avoid tripping GFCIs, receiving all the noise from electronics in your home, among other issues.

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  • $\begingroup$ Thanks! So if I do decide to try to use it as antenna, where would the counterpoise be placed? $\endgroup$ – Skyler 440 Jun 17 '14 at 18:20
  • $\begingroup$ @Skyler440 well, do you want it easy or hard? You could just let the counterpoise be whatever lossy Earth is already in place. Not terribly effective, but easy, and at low power, won't do any harm. Or, you could somehow isolate the wires from ground at RF (such as with a trap), then feed it somewhere in the middle like a dipole, then it has its own counterpoise. You could use something like a gamma match to help tune it, and also feed it in the center without cutting it. Lots of options. $\endgroup$ – Phil Frost - W8II Jun 17 '14 at 18:43
  • $\begingroup$ Ok thanks! I will be getting a rig soon, so I will do some experimenting. $\endgroup$ – Skyler 440 Jun 20 '14 at 14:06

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