Topband: Modeling the proverbial "vertical on a beach"

Tom W8JI w8ji at w8ji.com
Tue Aug 12 11:01:32 EDT 2014 

Just to set the record straight, I have no doubt saltwater helps propagation 
at most angles.

I probably did not make my point very well. My point is, with no comparison, 
an "impression" or "feeling" is not convincing data. It doesn't mean a 
thing.

I think this is a pretty simple concept. Not having proper comparative data 
is what allows all sorts of misplaced voodoo nonsense, like 360 radials is 
worth 6 dB.

There is a huge  difference between the validity of an A-B comparison and 
running away with a feeling.




----- Original Message ----- 
From: "Carl" <km1h at jeremy.mv.com>
To: "Yuri Blanarovich" <k3bu at optimum.net>; <topband at contesting.com>
Sent: Monday, August 11, 2014 9:51 PM
Subject: Re: Topband: Modeling the proverbial "vertical on a beach"


> There have been reports of verticals and salt water almost as long as 
> there has been radio. It helps horizontal antennas also.
>
> Ive operated for enough years aboard USN ships to know it is often a band 
> opener and have to laugh at a couple of petty comments. The difference 
> between operating shipboard and MARS/ham club stations was often a couple 
> of hours and even with big yagis there was no comparison. Go back to the 
> ship tied up at the pier or at anchor and the band was wide open again and 
> again, and again.
>
> After awhile you learn to ignore the nattering nabobs of negativism.
>
> Carl
> KM1H
>
>
>
> ----- Original Message ----- 
> From: "Yuri Blanarovich" <k3bu at optimum.net>
> To: <topband at contesting.com>
> Sent: Monday, August 11, 2014 9:30 PM
> Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
>
>
>> One pony needs to get into one drag radio car and drive around the ocean 
>> front, over the bridges, back over the land and watch the S-meter and 
>> listen to the bands. Observant would see 10 - 20 dB difference in signal 
>> levels in "lousy" mobile, especially on low angle propagation.
>>
>> Examples: Driving around Sydney, NS and listening to Disney 1670 AM in 
>> NJ - no signals over land, full quieting solid signal while driving on 
>> bridge over salt water.
>> While contesting as N2EE from Cape Hatteras, NC on 10m in contest, was 
>> told by ZS6EZ to be the first NA he heard, with vertical on the beach.
>> Results of "Team Vertical" speak for themselves.
>> Some of us do know. The reverse beacons testing can verify or legitimize 
>> modeling program's "calculated guessing".
>>
>> Yuri, K3BU.us
>>
>>
>>
>> On Sun, Aug 10, 2014 at 11:02 PM, Tom W8JI wrote:
>>
>> > 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" To: "Tom W8JI" ; 
>>> "TopBand List" 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" To: "TopBand List" 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" To: "Guy Olinger 
>>>>> K2AV" ; "Richard Fry"
>>>>> Cc: "TopBand List" 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" To: "Richard 
>>>>>> Fry" Cc: "TopBand List" 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  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
>>>>>>>> _________________
>>>>>>>> Topband Reflector Archives - http://www.contesting.com/_topband
>>>>>>>>
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>>>>>>
>>>>>>
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>>>>>
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