> Anyone tried a string of resistors in series that equal the needed
termination.
> ? No downlead on the termination end just a long resistor.
This is like a loading coil problem or a string of beads on coax Bruce.
Unless you have very low shunt capacitive reactance to ground (or to another
large object around the resistor string) compared to the load impedance at
each end of the string, the current into one end has to equal the current
out the other. There is no way around that.
The charges flowing in one end can't vanish, they either are shunted off in
other paths by displacement currents or they appear at the other end.
The response would be essentially the same no matter how the resistors are
distributed. I'm afraid there isn't any way around this problem, besides
moving the ground up to the antenna or the antenna down to the ground. I'm
convinced it is a very small problem, if ever a problem at all.
Why?
Listen to the sound files on my DX sound web page as I change antenna
directions. None of these antennas have sloped ends. How much better could
they get?
Once the gain in the unwanted direction suppresses noise to less than the
accumulated noise power from desired directions, additional F/null ratios
are totally meaningless. Think about that. If I have noise power 15dB
stronger than the total noise power from all other directions (and that is
SIGNIFICANT) from the south quadrant while listening west, once I have a few
dB more than 15dB null ratio between that quadrant in the south area and the
west response having more null won't help a bit.
While there are exceptions, big F/B or big F/S just makes us feel good
rather than hear better. What we really want is highest RDF over the long
term, and a null that doesn't allow one noise direction to overwhelm us if
we have a constant problem direction.
I think the biggest evidence of how overrated this problem really is can be
seen if we look at the things that do nothing that are reported as
solutions. If the inventors really had a problem, wouldn't they have noticed
they didn't do anything to solve it?
73 Tom
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