It isn't the feedpoint impedance that matters, it is the antenna radiation resistance that matters. For example, if we take a quarter wavelength vertical having radiation resistance of 36 ohms and add a wire to make it a folded vertical having input impedance of 144 ohms it still has a radiation resistance of 36 ohms. The ground loss eats up the same amount of RF energy.
To increase the radiation resistance the current-area must be increased. Two ways to do that are to lengthen the antenna (up to 1/4 wavelength) or top load it. On 60 meters1 the HF2V is a 32' base loaded vertical having a radiation resistance of ~1.5 ohms. Top loaded this can be increased to ~5.5 ohms, potentially increasing your signal by almost 6 dB. The HF2V manual mentions top loading on page 11. *HF2V manual* https://static.dxengineering.com/global/images/instructions/but-hf2v_ck.pdf Dave KH6AQ On Wed, Mar 10, 2021 at 3:07 AM Richard Quick <[email protected]> wrote: > I have as much of a compromised antenna for 160 as you can get. > A Butternut HF2V with a 160 coil, mounted on a chain link fence. > I have a small lot with overhead power lines across the back of the > property, and Am looking for a better idea. > I’m thinking a hi impedance feed point antenna ie:450 ohms would require a > much less extensive ground radial system than say, an inverted L with low > impedance. Easier to match a 450 Ground than 37 ohms. > Am I nuts? Anyone with ideas along this line of thinking? > > > > Rich - W4RQ Amateur Radio: The Original Social Media > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
