The conductivity chart for the continental U.S. published by the FCC shows a conductivity of 8 mS/m for the Great Lakes. Below is a link showing the groundwave coverage contours of WATZ in Alpena, MI
The radiator configuration in the OP by Paul N0AH could provide some rather good performance on 160m. Below is a link to calculations showing the inverse distance groundwave fields it could produce a
That isn't exactly correct, Guy. The 1937 real-world experiments of Brown, Lewis & Epstein of RCA Labs includes measured data for sets of of radials varying in number from 2 to 113, and in length fro
________________ The complete data/paper from BL&E is available as item 4 at http://rfry.org/Software%20&%20Misc%20Papers.htm _______________________________________________ UR RST IS ... ... ..9 QS
Guy: Below are responses to a few of the statements in your recent post on this topic. miscellaneous downward extrapolation of dense and uniform radial systems. The purpose of the BL&E experiments wa
The data taken by BL&E applies to different conditions than the data plotted in my paper. The BL&E data shows the groundwave field from monopoles where the propagation path is so short that the affec
Guy - some selected comments to your recent post on this topic... If 15 and 30 radials were/are dunned by BL&E, how would that legitimize the use of even fewer of them by hams? But in any case, the B
The maximum power radiated by a short monopole antenna system may be calculated using equations found in standard engineering texts. The link below shows a system with a 50 ft monopole radiating 1 wa
The link below leads to two graphics showing the __accurately measured__ fields using various numbers of buried radials of 0.274 and 0.412 wavelengths (radial lengths as measured in free space). Thes
Just to note that the graphics I linked to were part of the 1937 benchmark experiments and I.R.E. paper of Brown, Lewis & Epstein of RCA Laboratories, and is the basis for the FCC requirements for th
Those tending toward such beliefs should be interested in the clip at the link below, as well as the BL&E study linked earlier in this thread. Note the logical conclusions therefrom that the radiatio
This link http://www.commtechrf.com/documents/nab1995.pdf leads to a paper by Clarence Beverage with some real-world results for monopoles with elevated wires used as a counterpoise. Here is a quote
The FCC requires minimum "efficiencies" for the radiators of various classes of licensed AM broadcast stations, expressed as the r.m.s. field intensity of the ground wave produced at 1 km for 1 kW of
RE: Mike Waters asks: It is universally common for the highest radiated fields launched by vertical monopoles to occur in the elevation sector between the horizontal plane and 5 degrees above the hor
Carl KM1H wrote [sic]: It certainly wasn't by their ground/surface wave, but their skywave. As to how many hops that took, please note that it would take fewer hops to produce a useful field intensit
All vertical monopoles of 5/8-wavelength __and less__ radiate (launch) their maximum relative field (E/Emax) in the horizontal plane. This is true no matter what the loss in the r-f ground connection
Note in the link below that the value of the surface wave at 1 km at an elevation of 50 meters is about 110 uV/m, which is not much less than the 113 uV/m field shown by the NEC far-field analysis at
If that were true, the low-angle radiation would not move up to create a lobe centered on a "takeoff angle." But in any case, the graphic linked below (Terman) does not show a lack of radiation from
A common use for correctly defined NEC models shows the electrical characteristics of the radiator system itself. But NEC also will show the field intensities that system will produce at a given dist
Groundwave propagation losses increase directly with frequency and inversely with earth conductivity. However my statements in this thread, and the graphics I have linked to do not support the concl