Yes Guy, I agree. Another area that is overlooked perhaps through a lack of room is the need with short verticals to have longer radials to get back the system efficiency. Take my own as an example I
Indeed. But if the longer radials put your wire in your neighbor's back yard, or run out into the street, or into your basement, then radials need to be abandoned as your counterpoise solution. That
That of course will tell you the antenna is fairly Low Z, in order to get the efficiency back to as high as possible I laid 130 x 0.4 wave radials. With this I know that the effective series ground r
Radials into neighbors back yard? Yep. At least on contest nights! Radials across basement ceiling and out other side of the house? Yep. Radials across garage floor, out garage windows, through bushe
Radials do have standing waves, and so the minimum impedance at the base will appear when the radial is somewhat less than 1/4 wave long. Of interest here is that the benchmark Brown, Lewis and Epste
Of interest here is that the benchmark Brown, Lewis and Epstein I.R.E paper on ground systems does not show such standing waves along buried radials (clip below). Of interest down here is surface-bur
Their Fig. 7 shows results of simplified (manual) calculations, not measurement results. Quoting from page 771 of the BL&E paper on ground systems: "The current in the buried wires was measured in ea
That quote does not apply to Fig. 7, which is 10 pages earlier. This quote from p. 760 applies to Fig. 7: "...the following calculations are made on this basis. The current in the wires is shown...
Earth resistance/voltage would not necessarily be exactly the same for each radial, depending upon the earth site.. If memory serves me correctly, think it was W7EL who found standing waves on some r
Additional from the BL&E paper on the subject of standing waves on buried radial wires... Figure 11 linked below is based on the r-f currents measured along the radial lengths shown in Figure 7. http
Not only that, but it defies logic that radials would NOT exhibit the same current and voltage distribution of any other conductor carrying RF current. The boundary condition is near zero at the end
There is a bit of explanation and clarity in BL&E regarding standing waves on radials that does not show up until page 781 and figure 42. ** Emphasis added. "The current in the buried wires **for an
Not only that, but it defies logic that radials would NOT exhibit the same current and voltage distribution of any other conductor carrying RF current. The boundary condition is near zero at the end
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
For those who'd like to read the whole paper, you can access it here http://bit.ly/1LLdtCI Jeremy _________________ Topband Reflector Archives - http://www.contesting.com/_topband
All As far as I can understand, wires / radials just under the surface of the ground are simply conductors embedded in a lossy dielectric (with an interface to air near it), similar to carbon filled
... 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.
A monopole will not radiate without a return path for the r-f current flowing into/on it. In the case of a ground-mounted vertical monopole, the first part of that return path is provided by the capa
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