'SMALL' ANTENNA CRITERIA
On Feb 15, 6:46 pm, art wrote:
On 15 Feb, 15:29, (Richard Harrison) wrote: Art wrote:
"My present antenna, which is for 160 m and above, is about the size of
two shoe boxes and is less than 2:1 swr (50 ohm) across the band when
situated at the tip of my tower."
Outstanding! An effective antenna needs to be an appreciable portion of
wavelength in some dimension.
If Art`s antenna is an appreciable portion of 525 feet it can radiate
well on 160 meters.
Any length of wire carrying an RF current is capable of radiation.
*******
Yes, but it is not useable if C and L for the length involved and
frequency of use is not adhered to.
Implicit in Maxwell's laws is that a radiator can be any size or shape
as long as it is in equilibrium. Without the inclusion of that last
word
all laws of the masters are invalid.
Define equilibrium. As far as I can tell, you seem to infer
that being in "equilibrium", means that it is resonant.
I hate to break it to you, but being resonant is no sure
road to efficiency as a radiator of RF.
How many hundreds of feet of wound 22 gauge wire does this
device contain?
Seems to me, if I ponder all the laws of the "masters",
you have reinvented an air cooled dummy load that probably
won't handle too much power before it becomes so hot as
to melt whatever is close to it.
Maybe I suggest a Heathkit "Cantenna" as a better oil
cooled substitute that can be ground mounted for ease of
use. You can blast it with your 8877 for short periods
of time, and I doubt it will melt any plastic that is lying
next to it. Requires no tower, and no need for garbage can
lids.
According to the law of Art, it is in equilibrium, and
should satisfy all the requirements of the masters,
whoever they may be, and wherever they may lie.
MK
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