Yes, Mark, N5OT go back a long way, 80's or so. At my QTH, Arizona high desert 4800ft, the soil is very non-conductive - typically dry shale and small rocks, it's called Caleche. We have very little rain, about 10" - 12" per year. Humidity very seldom goes above 30%, and temps in the summer are in the 90's. The first 6" of soil can be dug with a shovel, but below that it takes a backhoe further. The ground below 2ft has probably not seen water since it was laid down eons ago.
With said, I believe my ground absorption is very high so I feel the higher numbers of radials helps greatly with my vertical efficiency and radiation. Ray, N6VR/W7YA On Thu, Dec 10, 2020 at 4:09 PM Jeff Blaine <[email protected]> wrote: > N6LF Rudy's web site and associated QEX series has empirical data to > answer all of these questions regarding the number and length of on > ground radials. > > 73/jeff/ac0c > alpha-charlie-zero-charlie > www.ac0c.com > > > On 12/10/20 11:14 AM, Mark - N5OT wrote: > > Yeah. I don't claim to be a radial expert but I do claim to have a > > lot of experience working other stations on 160 meters. > > > > My buddy W9RE told me on a DXpedition once that he built a dipole > > laying on the ground and it resonated on 160 when the wires were about > > 80 feet long. > > > > Ray, with respect (N6VR and I go back a LOOOONG way), I think 80 feet > > is the "new quarter wave radial" on 160, and frankly the only thing I > > really think I understand about verticals is, the more wire on the > > ground, the better, but you can get to a point where adding more is > > not worth the effort, YMMV etc. > > > > My story for the week is: I put up yet another temporary 160 vertical > > for the ARRL 160 last weekend, and only managed 14 radials before it > > got so dark I thought I better be getting on the air. > > > > I worked 970 QSOs that night, including 5 Europeans, and while I was > > out there on Saturday adding more radials, I got a text from K5ZD > > saying I was an alligator, that I was very loud the night before, but > > couldn't hear him calling me for 10 minutes as he needed Oklahoma. > > > > So I stopped adding radials, I was up to 22 radials at 80' long, and > > moved on to listening antennas. > > > > Worked maybe 10 Europeans and counted 10 JAs, so I know my signal was > > getting to those places. > > > > That's really all I know about that. > > > > The vertical is 50 feet tall and has two symmetrical top-load wires > > that bring the resonant frequency to 1.8 MHz. > > > > 73 - Mark N5OT > > > > P.S. Got an email from a guy in South Dakota who worked 376 QSOs > > (including 4 other countries) using an inverted L that was 20 feet up > > and the rest horizontal, fed against 20 radials 25' long in his yard. > > I love stories like that. > > > > > > On 12/10/2020 9:52 AM, Wes wrote: > >> IMHO, for that number, on-the-ground radials do not need to be > >> anywhere near that long. Personally, I subscribe to the > >> same-length-as-the-vertical guideline. > >> > >> My inverted-L is 55 feet of vertical tubing plus the horizontal > >> wire. My insulated, on the ground radials are 55.5 feet (9 radials > >> out of a 500 ft roll of wire). By serendipity, measuring one radial > >> against all of the rest with a VNWA it is resonant at 1.84 MHz. To > >> be fair, I still have fewer radials than planned (18 vs. 36) in which > >> case, shorter is actually better according to Belrose and Severns > >> ( > https://www.antennasbyn6lf.com/files/antenna_ground_system_experiment_4.pdf > ). > >> > >> Wes N7WS > >> > >> > >> On 12/9/2020 7:00 PM, Raymond Benny wrote: > >>> If your vertical is ground mounted you need alot [sic] more. I'd say > >>> atleast 36 > >>> radials, 135ft long. It will make a big difference in your signal > >>> and be > >>> easier to match. > >>> > >>> I have over 100 radials but probably an over kill, but I feel I have > >>> a good > >>> signal on 160m. > >>> > >>> Ray, > >>> N6VR/ W7YA > >>> > >> > >> _________________ > >> Searchable Archives: http://www.contesting.com/_topband - Topband > >> Reflector > > > > _________________ > > Searchable Archives: http://www.contesting.com/_topband - Topband > > Reflector > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
