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21. Re: Topband: Monopole Radiation Patterns, takeoff angles etc (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 8 May 2012 10:18:06 -0500
Assuming those angles are true for DX paths, note that if the NEC far-field elevation pattern for a 1/4-wave monopole was the only radiation leaving the antenna, the field at 3 degrees elevation woul
/archives//html/Topband/2012-05/msg00117.html (9,087 bytes)

22. Re: Topband: Monopole Radiation Patterns, takeoff angles etc (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 8 May 2012 16:22:55 -0500
Those who believe so might want to review the conversion from the e.m.u. units used for earth conductivity in the BL&E publication to the mS/m units more commonly used today. factor of ten. <-- Other
/archives//html/Topband/2012-05/msg00122.html (9,689 bytes)

23. Topband: Effect of Earth Conductivity on a Buried Radial Field (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Mon, 4 Jun 2012 09:39:48 -0500
As an observation... The link below shows how the r-f ground connection loss and system radiation efficiency of a 10m monopole using a set of 32 x 10m radials vary with the conductivity of the earth
/archives//html/Topband/2012-06/msg00029.html (6,900 bytes)

24. Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 24 Aug 2012 08:39:23 -0500
A common belief seen on the web is that if buried radials are not installed over some azimuth sector around a monopole, then the azimuth radiation pattern of that monopole will become distinctly dire
/archives//html/Topband/2012-08/msg00285.html (7,943 bytes)

25. Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Fri, 24 Aug 2012 12:58:04 -0500
The number and length of equally-spaced buried radials needed for a monopole depends rather heavily on the conductivity of the earth in which they are buried, and how close the operator needs/wants t
/archives//html/Topband/2012-08/msg00290.html (7,664 bytes)

26. Re: Topband: Elevated Radials on Grounded Tower? (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 20 Sep 2012 19:00:34 -0500
Earlier... I hope we all caution people models are models and can vary from life, and that empirical reports should be taken with a grain of salt. ____________ Good advice, but probably anecdotal rep
/archives//html/Topband/2012-09/msg00200.html (7,964 bytes)

27. Re: Topband: Ground Screens - Another Small Space Option (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 25 Sep 2012 17:23:13 -0500
Just to note that Edmund Laport (once the Chief Engineer of RCA International) did not support the use of ground screens in his textbook RADIO ANTENNA ENGINEERING (page 121), citing eddy current loss
/archives//html/Topband/2012-09/msg00264.html (8,404 bytes)

28. Topband: Short radials? (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 27 Sep 2012 12:14:23 -0500
The measured data linked below shows how the number of buried radials affects the performance of monopoles of various height to 90 degrees, for an applied power of 1 kW. Earth conductivity at the tes
/archives//html/Topband/2012-09/msg00282.html (7,034 bytes)

29. Re: Topband: Short radials? (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 27 Sep 2012 18:38:19 -0500
Can you pass along your source of information that BL&E was done over 4 mS/m soil, ... Or are you using the FCC map for typical soil conductivities and presuming a common New Jersey value and no vari
/archives//html/Topband/2012-09/msg00300.html (10,144 bytes)

30. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 2 Oct 2012 13:58:04 -0500
Conclusion: The less ground conductivity the higher is the antenna elevation radiation angle. This is a negative impact for DX! Cris, Tom, Paul et al This belief is common when looking at the far-fie
/archives//html/Topband/2012-10/msg00069.html (11,561 bytes)

31. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 2 Oct 2012 14:33:58 -0500
On your referenced fields graph you caption "Measured vs. Calculated" intensity, but the traces are not differentiated. Which traces on the graph are measured and which are calculated? ______________
/archives//html/Topband/2012-10/msg00075.html (9,141 bytes)

32. Re: Topband: ground characteristics (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 08:38:18 -0500
Guy Olinger wrote (about measuring earth conductivity): Figure out how to do that for a small lot backyard in an old European village with 900 year old homes. Here is one method: http://www.technik.d
/archives//html/Topband/2012-10/msg00135.html (7,956 bytes)

33. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 09:03:00 -0500
From Terman (as Richard Fry mentioned): http://i62.photobucket.com/albums/h85/rfry-100/TermanFig55.jpg First hop distance on E layer reflection for given angles is: 20 degrees = 300miles, 30 degrees
/archives//html/Topband/2012-10/msg00140.html (10,707 bytes)

34. Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 11:05:53 -0500
The elevation patterns of vertical monopoles over real earth has been discussed in recent threads here (http://lists.contesting.com/archives//html/Topband/2012-10/msg00140.html). The common belief ba
/archives//html/Topband/2012-10/msg00154.html (9,517 bytes)

35. Topband: Topband ground characteristics (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 12:25:59 -0500
I have not been able to locate these FCC curves (and it appears that they may have been withdrawn). Here is the link... http://www.fcc.gov/encyclopedia/m3-map-effective-ground-conductivity-united-sta
/archives//html/Topband/2012-10/msg00156.html (7,191 bytes)

36. Topband: Topband ground characteristics (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 17:05:32 -0500
I have not been able to locate these FCC curves (and it appears that they may have been withdrawn). The FCC groundwave MW propagation curves are available here... http://www.fcc.gov/encyclopedia/am-b
/archives//html/Topband/2012-10/msg00163.html (7,476 bytes)

37. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 4 Oct 2012 04:54:11 -0500
Guy Olinger wrote: But to prove it we can't use standing-man-with-meter. He may just be sensing the current in the ground just below his feet that will never be airborne. We need sitting-man-with-met
/archives//html/Topband/2012-10/msg00168.html (11,075 bytes)

38. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 4 Oct 2012 08:40:04 -0500
We need sitting-man-with-meter-in-helicopter to go up there and prove that what you get from the ground up to twenty thousand feet out (at) 20 miles is a blend, and not a notch. Below is a link to th
/archives//html/Topband/2012-10/msg00170.html (8,708 bytes)

39. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Thu, 4 Oct 2012 18:23:02 -0500
I get that at any point in the far field there is RF current in the ground due to the space wave from the transmitter reflecting obliquely off ground. If the earth had perfect conductivity then an EM
/archives//html/Topband/2012-10/msg00174.html (10,104 bytes)

40. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Sun, 7 Oct 2012 05:42:50 -0500
Guy Olinger wrote: I find it curious that some of those that so insist on standing-man-with-meter in affairs regarding performance of antennas are willing to accept a considerable logical reach on "u
/archives//html/Topband/2012-10/msg00185.html (12,120 bytes)


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