> The 10.1MHz antenna works beautifully - I snagged YV0D
> the first call after I found his listening frequency
> last night in a major pileup. The 7MHz antenna is a
> dog, which is very easily beaten in all directions and
> distances by a dipole at 40'. (The dipole is about
> 300' from the verticals and has a higher loss
> feedline.)
>
> Now why should that be?
I've had poor luck with verticals on 7MHz also Roger. The
exception is when they are mounted 100 feet or higher in the
air.
First a quick comment about suggestions you elevate the
radials. You already likely have near 100% feed efficiency.
Removing you good ground system and replacing it with four
elevated radials would get you back to 25-50% efficiency.
Although four elevated radials are better than 8 buried,
there is no possible way they or anything else would be
better than what you have. I would not look at ground losses
very near or in the antenna system as an issue. I would look
at Fresnel zone losses, however!
My 200 ft vertical on 160 with 100 200ft long radials equals
or beats a 300ft high dipole broadside to the dipole. It
absolutely kills the dipole off the ends of the dipole.
My 35ft top loaded vertical for 80 with 50-60 long radials
equals a 100ft high dipole to Europe night after night, but
of course a dipole at 160ft wins.
On 40 meters, almost any dipole height I've tried beats a
35ft ground mounted vertical with 50-60 long radials at any
distance and any time as long as a contact isn't off the
ends of the dipole.
So now the question Rodger, you worked the YV0 on a band
where almost nobody runs power, much less people use
compared to 40, and most antennas are makeshift and big
Yagi's are not common. What does that really tell you? Only
that you are better than a tiny pack of snarling dog-gnats.
The real question is how does the 30M vertical antenna
compare to a 30M dipole in an A-B test? Did you ever do
that?
73 Tom
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