In a message dated 1/22/2001 12:36:50 PM Eastern Standard Time,
n5nug@ix.netcom.com writes:
>
> I compared a 34' tall 40m vertical monopole antenna located about
> 75' from a 31' top loaded folded vertical (4 skirt wires) antenna
> about 8 years ago. I compared the two antennas A-B fashion on 40m
> for noise as well as signal strength. The monopole was matched with
> a loading coil to the 50 ohm feed line. The top loaded folded
> vertical was capacitor coupled to the skirt system for a 50 ohm
> match. Both antennas had the same number of radials (60) 34' long
> (thanks to a neighbor to my east).
...
> Top loading was via a 17' diameter (8 spokes) top hat assembly with the
> outer perimeter of the spokes tied together with #14 wire. The
> natural resonance point for the top loaded vertical was about 2.4 Mhz.
It appears that two different antennas were compared, with different
radiation patterns. One quarter wave (monopole) vs. top loaded folded
vertical that was resonant around 2.4 MHz. Folded vertical would have
different pattern (lower angle and more gain), so comparing them and serching
for answer to cure for precipitation static is not exactly appropriate.
I think that comparing monopole to shortened, loaded and folded vertical
resonant on the same frequency (same pattern) would be more representative.
Yuri, K3BU
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