On 4/27/2014 12:58 PM, Jim Allen wrote:
Yes, I read a good deal of that. They have argued it, but no one has
demonstrated it, and AFAIK, no one has modeled one.
That's because it's not practical to model it in most modeling software.
In the meantime, a
good number of folks, including some who are quite expert, say they are
getting gratifying results.
That's meaningless, unless MANY ON THE AIR comparisons are made with a
reference antenna between the same stations at the same time. As N6BT
(designer and original owner of Force 12) has shown, EVERYTHING "works,"
sort of. He demonstrated this by working all continents in a short
period with 100W into a light bulb as his antenna. In the 8 years I've
lived in CA, I've worked about 135 countries with 5W and great antennas,
and 311 countries with 1.5kW.
There is no way a loop is a superlative antenna, and you
wouldn't chose that if you had space, no restrictions, adequate budget
etc.
Right. But it's those restricted conditions we're talking about.
The helically loaded loop gets you the same performance of a magnetic loop
but at reduced size, supposedly.
"Supposedly" means in the optimistic and vivid imagination of the guy
who came up with it.
IOW, the 80M loop that is 6' in diameter can be 3 or 4' when helically loaded,
so it is said.
The only thing that the helical loading does is add inductance, which
changes the tuning.The laws of physics make it unlikely that it will
improve radiation efficiency.
I'm looking at a one meter loop for 20-10M, then we'll see.
Again, you won't know until you do serious comparisons with other
antennas, between many stations, at the same time, and average a LOT of
such data. Until you do that, it's no more meaningful than if you say
you called someone and he came back to you. :)
73, Jim K9YC
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