Thread: Radiating coils
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Old June 6th 10, 03:36 AM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Radiating coils

On Jun 5, 6:59*pm, Art Unwin wrote:
On May 27, 6:22*am, K1TTT wrote:



On May 23, 2:17*am, Art Unwin wrote:


I just modeled two coils counter wound and one inside the other as a
complete closed circuit , end fed. Counter winding is quite the norm
with special purpose machinery to prevent inter tangling of coils when
compressed.
With the coils wound opposite to each other
it made quite a nice antenna when placed on a flat plate. Beam was
pencil shaped without side lobes and sensitive to all polarities.Thus
any such dishes could be used for 'point to point' using any type
circular polarization. *Smaller in size compared to other designs is
rather obvious. Where Kraus determined such an antenna single wound
form demanded a certain angular pitch such a requirement is not
apparent with this design. Kraus assumed a certain pitch was required
when wave composition clashed, but the opposite happens when particles
vectors add. Another example of particle versus waves disputes.It also
confirms Maxwells equation by removing the effect of lumped loads
which was not included in his equation as was not the stipulation that
a radiator must be straight.


Caution:
Above details not yet "printed" in a book so it must be considered
questionable.
Regards
Art


you have a nice little web site, please publish the design file and
picture of the antenna so we can all have a good laugh at it.


I expect to put some more things on my page
especially the model that I am honing now.
Now I have a 8 inch dia coil about 4 inches high relatively close
wound. Inside is the counter wound coil connected to the other coil to
make a closed circuit. It is placed on a perfect ground in leau of a
reflector. What I have done is balanced the inductance with the
capacitance, *as you move around in frequency it will always be close
to resistive because of the balancing I have done.
It takes a while for the program to work from near
near resistance (.01 ohms) and I have now reached 11 ohms for 16.5 dbi
gain where the lower resistance gave me about 30 dbi
The resistance values are wave like as is the variation in gain per
cycle. Field shape so far varies from elliptical to something like the
double. zepp. My intention is to plot up to 20 ohms and that will take
several times longer than that taken already. The model has about a
dozen sections per
winding and I am pretty much limited to 10 segments per section. All
very interesting because I am following the idea of canceling all
lumped loads in line with Maxwells laws that deals only with
distributed loads. Frequency range covered up to now is 685 to 1200Mhz
With this amount of information you can start laughing now *well
before I put it up
Art


just did a check at 3 Ghz. 20 dbi at 5 ohm resistive
so I may not get to 20- ohm resistive So after I get a reasonable
graph I will have to modify the model
to see if I can increase the resistance spam.
Note that the metallic resistance calculated is to gauge losses and is
not the source impeadance