Hello to all,
I finally found the time to add the final set of radials to the
1/4wl tower vertical(122ft). I recorded the SWR changes after adding radials in
groups of four. Here is what I was seeing(see below) on the swr meter of my
FT1000MP. My original post showed up to 46 radials. I added two in the interim
until today's additional 12 and recorded the swr measurements after adding an
additional 4 at a time. A sidenote-
When I originally had only 12 radials I kept the radial connection point at the
base of the tower "ungrounded". When I grounded the radial connection point the
center frequency increased 6 KCs. When I repeated this test at 48 radials the
center frequency increased 1 Kc.
Now that I am at 60 radials the center frequency does not increase at all when
the radial connection point is grounded. I also noticed that the 1.2:1 points
have also gotten wider as I added more radials even though the full 1.5:1
bandwidth has decreased. I think I have finally achieved ground radial
"Nirvana". As the famous boxer Roberto Duran said; "No Mas". Too much trouble
to add anymore radials and I don't think I'd get much more in the results
department. What does this all prove? It proves that all you guys who told me
that 60 radials was the minumum needed were right on target. Sure, I could have
just believed everyone and went right to 60 radials and not taken measurements
but if Christopher Columbus would not have had his doubts and had just gone
along with the consensus about the world being flat I might still be tending my
flock of sheep on some hillside in Spain.
The antenna seems to be working quite well based upon some of the
reports I have been getting from the DX on 160. It helps that I have also
improved my receive situation quite a bit too! See you all in the pileups 73,
Ken, N4UK
# of radials 1.5:1 points Center freq. Increase Bandwidth
30 1778-1849 1813.5 71khz
34 1784-1854 1819 5.5 70khz
38 1790-1857 1823.5 4.5 67khz
42 1791-1858 1824.5 1 67khz
46 1794-1860 1827 2.5 66khz
48 1795.5-1860 1828 1 64.5khz
52 1797.5-1860 1828.5 .5 62.5khz
56 1798.5-1860.5 1829.5 1 62 khz
60 1799.5-1861 1830 .5 61.5khz
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