Guys,
First shot on converting the CC D40 40 Meter
rotary dipole to 30 M seems to indicate success.
I just took some aluminium wire and shorted out
the traps by using stainless steel ring clamps on
either side of the traps.
Next I legthened the elements 3" on either side by
extending the last section to maximum.
The capacity hats were left in place.
At a height of 12' the following SWR curve was
obtained.
Freq SWR
10.000 1.5
10.050 1.4
10.100 1.25
10.150 1.1
10.200 1.0
I expect the resonant frequency to move up as the
antenna is raised.
My solution will be to just add a few inches of
tails (via cable clamps) with some aluminium wire
as required. I suppose one could get the required
extra length by other means.
Let you know the final results when I get back my
rotor and raise the antenna to full height.
73 de Brian/K3KO
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