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 <KeepWalking188@ac0c.com> 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
> >>>
> >>
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