Re: Topband: Modeling the proverbial "vertical on a beach"

["Tom W8JI" <w8ji@w8ji.com>]

My point is if no one else is on, we really don't how other signals would 
be. It's like a drag race with just one car, or a pony show with one horse.

----- Original Message ----- 
From: "Hardy Landskov" <n7rt@cox.net>
To: "Tom W8JI" <w8ji@w8ji.com>; "TopBand List" <topband@contesting.com>
Sent: Sunday, August 10, 2014 9:08 PM
Subject: Re: Topband: Modeling the proverbial "vertical on a beach"


> Tom,
> I was totallly not expecting any station from that direction, just thought 
> I'd work a few locals with high incident angles before Sunset here. Then I 
> heard the 6Y2 guys and it was amazing. He was the only station--no KV4FZ, 
> NP4A, etc and certainly no EU at our time. Made me a believer in beach 
> verticals.
> 73 N7RT
>
> ----- Original Message ----- 
> From: "Tom W8JI" <w8ji@w8ji.com>
> To: "TopBand List" <topband@contesting.com>
> Sent: Sunday, August 10, 2014 5:20 PM
> Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
>
>
> > How was his signal compared to someone from a similar heading and 
> > distance at the same time who was not on the beach?
> >
> > ----- Original Message ----- 
> > From: "Hardy Landskov" <n7rt@cox.net>
> > To: "Guy Olinger K2AV" <k2av.guy@gmail.com>; "Richard Fry" 
> > <rfry@adams.net>
> > Cc: "TopBand List" <topband@contesting.com>
> > Sent: Sunday, August 10, 2014 7:35 PM
> > Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
> >
> >
> > > Just an observation to all:
> > > When Tom, N6BT went to Jaimaca and operated 6Y2J (I think was the call) 
> > > with verticals on the beach I was blown away. I heard them 2 hours 
> > > before Sunset here on 160....nuff said. The proof is in the pudding.
> > > 73 N7RT
> > >
> > > ----- Original Message ----- 
> > > From: "Guy Olinger K2AV" <k2av.guy@gmail.com>
> > > To: "Richard Fry" <rfry@adams.net>
> > > Cc: "TopBand List" <topband@contesting.com>
> > > Sent: Saturday, August 09, 2014 8:35 PM
> > > Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
> > >
> > >
> > > > Just to mention that the prior opinion is controversial and not 
> > > > universally
> > > > agreed upon. Nor to date has anyone surfaced with actual measurements 
> > > > made
> > > > at the distances (25 to 50 km) and with span of altitudes (0 to 10 km) 
> > > > to
> > > > either prove or disprove either side.
> > > >
> > > > It remains unproven modelling from NEC at those distances either way. 
> > > > This
> > > > situation may, alas, persist this way, because the precise subject
> > > > resolution appears to be without benefit to any commercial interest and
> > > > therefore without funds to pay for some pretty expensive experimenting
> > > > involving precision measurements from aircraft.
> > > >
> > > > Additionally, there is considerable suspicion that moving from LF to MF 
> > > > in
> > > > this general subject involves a ground modal change of some sort that 
> > > > would
> > > > render 50x10 km measurments at 0.5 or 1 MHz unlike those at 2 MHz,
> > > > rendering commercial measurements at low and possibly high BC of no 
> > > > value
> > > > for extrapolation to ham use.
> > > >
> > > > Arguments on both sides remain basically intuitive. I have "reasonable"
> > > > arguments to BOTH concur with Richard AND to not. NEC near field
> > > > calculations over sea water at 50 km follow Richard's assertions, and 
> > > > the
> > > > same over "average" ground does not. The model clearly thinks that 50 
> > > > km
> > > > over most types of ground slowly dissipates low angles resulting in the
> > > > controversial "notch" in low angle elevation patterns.
> > > >
> > > > So NEC based modelling cannot be used as a proof text to decide an 
> > > > argument
> > > > NEC has with itself.
> > > >
> > > > 73, Guy K2AV.
> > > >
> > > >
> > > > On Sat, Aug 9, 2014 at 7:23 PM, Richard Fry <rfry@adams.net> wrote:
> > > >
> > > > > Just to note that the low-angle radiation produced by monopoles is not
> > > > > accurately shown by a NEC model/study that does not include the 
> > > > > surface
> > > > > wave, regardless of whether one or two ground-plane media are 
> > > > > specified in
> > > > > the model.
> > > > >
> > > > > Below is a link to a NEC study of the low-angle fields of a monopole
> > > > > __including the surface wave__ for three values of earth conductivity
> > > > > ranging from extremely good to very poor.
> > > > >
> > > > > The curves there all show maximum relative field in the horizontal 
> > > > > plane.
> > > > > If the surface wave had not been included in these studies then all of
> > > > > those fields would have a zero value in the horizontal plane, and 
> > > > > reduced
> > > > > fields at low angles just above the horizontal plane.
> > > > >
> > > > > Reality is that radiation leaving the monopole at elevation angles of 
> > > > > at
> > > > > least 5 degrees decays at a 1/r rate.  Therefore that radiation is a 
> > > > > space
> > > > > wave which propagates in a ~ straight line to reach the ionosphere, 
> > > > > where
> > > > > (with suitable conditions) it can return to the earth as a skywave.
> > > > >
> > > > > NEC analyses of a vertical monopole of 5/8-lambda and less, and not
> > > > > including the fields of the NEC surface wave do not recognize the 
> > > > > radiation
> > > > > sector capable of producing the greatest single-hop skywave service 
> > > > > range
> > > > > that can be provided by that monopole.
> > > > >
> > > > > http://s20.postimg.org/9xqgzu9d9/Monopole_Low_Angle_Radiation.jpg
> > > > >
> > > > > R. Fry
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> > >
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> > >
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