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121. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 26 Feb 2015 00:31:50 -0600
Previously, from two different posters... ... it defies logic that radials would NOT exhibit the same current and voltage distribution of any other conductor carrying RF current. The ground sucks up
/archives//html/Topband/2015-02/msg00649.html (10,285 bytes)

122. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 27 Feb 2015 07:16:11 -0600
... As I understand, the primary loss mechanism for ground mounted vertical systems is EM field penetrating the lossy material below. To lower this loss, one needs to prevent this ground penetration.
/archives//html/Topband/2015-02/msg00714.html (11,273 bytes)

123. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 27 Feb 2015 12:35:48 -0600
Regarding the quotes below: 2.) We see any radial or counterpoise system, close to the radial or counterpoise, has to have external fields. Those fields must extend out of the counterpoise, and alway
/archives//html/Topband/2015-02/msg00729.html (12,086 bytes)

124. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 27 Feb 2015 14:33:48 -0600
... Simply put, the Newburgh area is at least a difficult area and at worst an entirely inappropriate area to test this thesis. ... Some may not be aware of the methodology used to determine the FCC
/archives//html/Topband/2015-02/msg00739.html (10,942 bytes)

125. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sat, 28 Feb 2015 07:33:58 -0600
Comments to two earlier posts by separate posters (clips below): But if indeed a less lossy ground means that fewer radials are needed to be placed in the field, then the coupling to the less lossy g
/archives//html/Topband/2015-02/msg00763.html (18,404 bytes)

126. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 1 Mar 2015 08:48:09 -0600
Reply to W8JI post of Sat, 28 Feb 2015 19:14:07 -0500: The source of the r-f current flowing on buried radials is the r-f current flowing in the earth as a result of radiation from the vertical monop
/archives//html/Topband/2015-03/msg00007.html (11,044 bytes)

127. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 1 Mar 2015 12:08:58 -0600
The feedpoint connection, in all cases of vertical antennas, whether the system is shunt fed or series fed, or even if it is an end-fed half wave, ties one feed terminal to the ground or counterpoise
/archives//html/Topband/2015-03/msg00018.html (8,954 bytes)

128. Re: Topband: Modeling "Ground" and losses (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Mon, 2 Mar 2015 05:35:41 -0600
Is it conventional to compare the surface wave fields at a distance so near the Radial length and the wave length? I chose a horizontal plane distance that would be just a bit into the far field radi
/archives//html/Topband/2015-03/msg00035.html (8,117 bytes)

129. Topband: Current Distribution on Buried Radials Used With Vertical Monopoles (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sat, 7 Mar 2015 04:55:28 -0600
For discussion... http://s20.postimg.org/kq2k6pox9/Current_Distr_on_Buried_Radials.jpg R. Fry _________________ Topband Reflector Archives - http://www.contesting.com/_topband
/archives//html/Topband/2015-03/msg00041.html (6,841 bytes)

130. Topband: BL&E: Dense vs. Sparse Buried Radials (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sat, 28 Mar 2015 08:34:01 -0500
Conclusions from graphics of the Brown, Lewis & Epstein ground systems experiments (linked below)... - When relatively few buried radials are used, there is little improvement in the GW E-field radia
/archives//html/Topband/2015-03/msg00221.html (8,970 bytes)

131. Topband: Current Distribution on Buried Radials Used With Vertical Monopoles & Brown paper (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 29 Mar 2015 06:28:52 -0500
With reference to the quote below from the interesting paper titled "The Brown Paper and Conclusions with a Ham Focus - N6MW March 25, 2015, linked in the OP of this thread title: \\ The field streng
/archives//html/Topband/2015-03/msg00227.html (9,036 bytes)

132. Re: Topband: Salt-Water Qth! (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 1 Apr 2015 08:42:32 -0500
Below is a link to the groundwave field of a 1 kW non-directional AM broadcast station located about 1 mile from the Atlantic, in Florida. The groundwave field shown is based on the FCC M3 conductivi
/archives//html/Topband/2015-04/msg00001.html (8,063 bytes)

133. Re: Topband: Salt-Water Qth! (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 1 Apr 2015 12:38:52 -0500
Have a look at 1KW 1130 AM on Hilton Head Island, SC (WHHW-AM). At 12 noon on any day, I can easily ride that signal down the Space Coast of FL and about 10 miles inland. That's the entire coast of G
/archives//html/Topband/2015-04/msg00015.html (8,884 bytes)

134. Re: Topband: Salt-Water Qth! (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 1 Apr 2015 13:18:08 -0500
Some may wonder why I posted the groundwave coverage contour of an AM broadcast station as being relevant to this thread. Hams are mostly interested in the space wave radiated by an antenna system. T
/archives//html/Topband/2015-04/msg00017.html (10,104 bytes)

135. Re: Topband: verticals by the sea (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 3 Apr 2015 04:34:30 -0500
NEC modeling to determine the effects on the fields radiated by a vertical monopole when siting it near a salt-water coastline can be highly misleading if the surface wave field is not considered. Fo
/archives//html/Topband/2015-04/msg00043.html (8,088 bytes)

136. Topband: "Sea Effects" on MW/HF V-Pol Fields (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 5 Apr 2015 10:34:44 -0500
Recent clips from one Topband post: ... EZNEC Pro4 can segment ground along a line into two arbitrary ground properties, ... The brief summary of modeling results is there is significant benefit at e
/archives//html/Topband/2015-04/msg00073.html (11,232 bytes)

137. Topband: RE "Sea Effects" on MW/HF V-Pol Fields (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 5 Apr 2015 11:04:39 -0500
There is a number mixup in my OP on this subject. Corrections to follow. _________________ Topband Reflector Archives - http://www.contesting.com/_topband
/archives//html/Topband/2015-04/msg00074.html (6,617 bytes)

138. Topband: RE "Sea Effects" on MW/HF V-Pol Fields (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 5 Apr 2015 12:48:03 -0500
When I first re-read my opening post on the Topband site I thought I had transposed some numbers in it, and posted that I would correct them. On further review I had not, so no corrections are necess
/archives//html/Topband/2015-04/msg00075.html (6,991 bytes)

139. Topband: Tee Antenna dimensioning (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 18 Oct 2015 13:38:08 -0500
A NEC4.2 model of a tee using a 60-ft tall vertical conductor shows 29 -j 0.04 ohms at 1.9 MHz when connected at the top to the center of a horizontal conductor 89 feet in length. The tee was base-dr
/archives//html/Topband/2015-10/msg00125.html (7,625 bytes)

140. Topband: 160 vertical/L (score: 1)
Author: Richard Fry <rfry@adams.net>
Date: Thu, 26 Jan 2017 18:54:42 -0600
Previously - __________ Below is a link from a followup post there with a NEC4.2 analysis of the performance of a 1/4-wave monopole driven against a set of 4 x 1/4-wave, elevated, horizontal radials.
/archives//html/Topband/2017-01/msg00084.html (6,587 bytes)


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