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Inverted Dipole Antenna Project for a Tight Space


If you have limited space for a multiband HF antenna, try using a "homebrew" inverted v dipole.

In this video from "Rob Braxman Tech", we see a step-by-step procedure for designing and using a simple inverted v dipole antenna.

As Rob suggests, this effort is a project in progress and will take some time to adjust performance and efficiency.

Here are some general comments from Rob:

I've set up an Inverted Dipole for use with my QRP HF Radio. Because it's QRP (Xiegu X5105), I wanted to do a good job with the antenna. I started with a painter's pole from Home Depot (extends to 23 feet), 12 awg household wire, and a cut off paintbrush which I initially used as the top of the painter's pole. The limitations of the project includes being in a hillside with a sloped backyard, and very little space. But I changed it and used a more permanent attachment with a Painters Pole adapter from Buddiepole.com and then PVC parts. This will make it easier to measure when the time comes. Each leg of the dipole was cut to approximately 33 feet. So 66 foot half wave. Height off the ground is around 26 feet. I can tweak this later and increase the height to 30 feet. Everything is adjustable. Painter pole has more length. Also, the height is not even since the bottom deck is actually suspended several feet above. So height above ground maybe better in some spots. The inverted dipole is tilted back. This is part of future experimentation to see if this is affecting the reception. I used the Xiegu X5105's SWR feature to scan the SWR for each band (really nice feature!) and this allowed me to quickly view where I have to tweak. This is not yet tweaked but it's passably resonant on 5 bands. Perfect for 40 meters which is what it was measured for. Did I hear any traffic? Barely. Maybe I have a QRM problem with a high noise floor being in the city. This is only step 1 of my journey. So that aspect of discovery will come later. Resonant at 40 Meters and 6 Meters. Partial resonance at 30, 17, 15 meters. I would have liked some resonance at 20 Meters but really bad SWR there. My feed line coax is 50 feet long. This is not a tuned length. It may have some impact. I coiled part of the feedline to act as a RF choke so the will reduce the length a little bit from 50 feet. I can experiment adding more coils (5 coils at the moment).

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Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM).
 

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