Your indoor antenna show them to me.


Just looked at a photo of the back of that tuner it looks like it also has screw terminals. You might be better off getting a 75 ohm to 300 ohm transformer with the spade connectors. The antenna’s coaxial should just screw on.
 
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Just looked at a photo of the back of that tuner it looks like it also has screw terminals. You might be better off getting a 75 ohm to 300 ohm transformer with the spade connectors. The antenna’s coaxial should just screw on.

Using a 75 ohm to 300 ohm transformer with the spade connectors will certainly work, although there can be some signal loss. Not all matching transformers are created equal. Some matching transformers may have as much as 3 dB of insertion loss.

Below is the correct adapter.

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Unfortunately not all suppliers supply what they list for sale.
 

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Since there has not been a response, the following is some general and somewhat simplified RF 101 regarding fractal antennas.



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The above antenna elements are closer to meandering wire or zig zag antenna elements.


In simple terms it is a form of linear loading of an antenna element, resulting in a shorter element for a given frequency of operation.

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The basic shape is called the generator.

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The picture below shows the higher order selfsame iterations of the generator pattern (stage 1) for a fractal antenna element.
In general the advantages of fractal antenna design do not start to become apparent until a higher level.

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This is because part of the magic comes from the interaction of the current distribution at the sharp angles in the higher orders as seen below. This can help allow multiband operation over a wide frequency range.

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The picture below shows a comparison.

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And remember that the meta-materials used in the construction of a fractal antenna play a large part in the design and performance of the antenna.
 
Thanks ILM. I'll take a look at the Olaode paper and see what I can get out of it.

Seems that @sinewaver has not been on AK this week, so maybe he will respond eventually with a link to that thesis.
 
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Gee, I never thought my reply to the OP's request would generate any interest at all. It's been years since I built this simple antenna and because it works so well, never gave it much time since. There is a wealth of info on fractal designs on the web and I did attempt to absorb as much as I could. They are at the core of cellphone tech. The 60 degree angle came from a project that an amateur radio operator had used with success and after the two pieces were formed, I made an adjustable holder so I could change the angles between. Fooling with the setup showed promise and surprised me with how sensitive the relationship is. Made for a couple of nights of productive fun. Once I settled on the relationship, I made a simple holder that I still use. I Love Music has presented here a good summary of the basics, The advanced designs are rather difficult to execute and I passed on those. The material is 1/8" aluminum wire and what was at hand. My first attempt used a thinner solid copper wire and didn't work nearly as well. Same for one made from coat hangers. That alone was educational. I'd love for somebody to experiment with this and compare notes. For me, it answered a need for a compact, self contained antenna. Been in use ever since. Would it work for everybody ? Probably not. No two situations are the same. My reference antennas were a "T" ribbon, rabbit ears and a Terk Pi.
 
There were two things that seemed interesting to me about your antenna. I thought the visual effect you achieved was quite striking and I was also intrigued by your comment that
Flipping one over so it matches the other causes a loss of signal.
From reading the paper that ILM mentioned, it seems that the resonant frequency, f0, of a meandered-line dipole will be intermediate between that of a straight-line dipole using the same amount of wire and that of a straight-line dipole with length matching the meandered-line one. (The paper doesn't say this explicitly but it is in their data.)

With your quarter-λ lengths of wire shaped into eighth-λ length meandered arms, the resonant frequency with 180 deg. between the arms would be expected to be significantly too high. But possibly your 90 deg. angle between the arms there is interaction that is pulling the f0 back down where you want it. (This is just speculation on my part.)

Thanks for the additional information.
 
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Because a generic Zig-Zag dipole antenna can be resonant at whatever length desired, the feed point impedance becomes a limiting factor.

With a generic Zig-Zag dipole antenna, the feed point impedance will fall from around 75 Ohms to around 50 Ohms at 0.8 ratio. At a 0.5 ratio (half length) the feed point impedance will fall to around 20 Ohms.

Remember that meandering antennas and zig-zag antennas are not the same.

I made reference to the paper by Olaode just as an example of a type of antenna design, while repeating in nature, is not what is typically thought of as a fractal antenna. The antenna elements in the rabbit ear type antenna under discussion are zig-zag antenna elements that repeat. This type of antenna is not necessarily thought of as a fractal antenna.

Both of these types of antennas do use self similar repeating sections (as does a fractal antenna), but as mentioned previously, they would be considered the generator section for the design of a fractal antenna.

The picture below is an example of a meander type of antenna. Note that this particular antenna tapers in width along its length. This can help improve the bandwidth of the antenna.

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Koch and Sirepinski are 2 types of Fractal antennas that are somewhat popular with the DIY crowd due to their ease of construction.
 
The comment (audiotemp) of the resonant freq being too high at 180 degrees would explain it's decreased performance I saw at that angle. My first thought was to make it like a folded dipole and present it like a bowtie. Not satisfactory at all. Arcing one element showed another drop at less than 60 and a complete cancellation as the elements came within an inch or so. Of interest might be that orienting the elements to present the most surface area was not as effective and further that it's reception node is on axis and not broadside. Please remember I only wanted a compact antenna and wasn't trying for any specific design. That led me to what I did / could do. The higher order Koch being difficult to execute and quite hard for me to determine the physical size of a Sirepinski design for the FM band. One of those might appear to be a metal sculpture if executed in copper sheet. I have a good supply of the aluminum wire yet and might try reducing it's size by changing the spacing between the 60 degree bends. Currently it's three inches. In my first post about this I did say (first order fractal ?) as more of a question of what it was. Nothing authoritative intended. It's an interesting indoor antenna that works. As much cut and try as solid research. Lots of fun experimenting with configurations and noting changes.
 
Using a 75 ohm to 300 ohm transformer with the spade connectors will certainly work, although there can be some signal loss. Not all matching transformers are created equal. Some matching transformers may have as much as 3 dB of insertion loss.

Below is the correct adapter.

View attachment 1253287

Unfortunately not all suppliers supply what they list for sale.
thank you so much. this arrived and it works. PAL was the keyword. i was orderring tyhe wrong thing. now i have 4 adapters that i dont know what to do with lol and its more expensive to return it to amazon so im keeping them and probsbly throw them in trash as they dont seem to ever become useful to me.
https://www.amazon.com/gp/product/B0084CCDWE/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B000I965YS/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

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does doubling up the dipole antenna help with reception? i know if the two antenna are a distance apart or in different orientations, the signal from them will be out of phase and not desirable, but what if the two are identical and over;ap perfectly and then at the tuner end their wires are connected so that the signal from both arrives at the tuner superposed and supposedly in phase?
 
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does doubling up the dipole antenna help with reception? i know if the two antenna are a distance apart or in different orientations, the signal from them will be out of phase and not desirable, but what if the two are identical and over;ap perfectly and then at the tuner end their wires are connected so that the signal from both arrives at the tuner superposed and supposedly in phase?


In the real world doubling up (2X) on antennas will increase the gain by about 3 db.

As an example the picture below shows a commercial band antenna consisting of 2 dipole antennas. Not that its gain is listed as 3/6 dBd.

The 3 dBd figure comes into play if the antennas are mounted as shown in the picture. If both are mounted on the same side of the support structure, the pattern becomes directional and the gain increases to 6 dBd.

The above applies when the antennas are mounted on a metallic support structure.

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If one uses a normal 2 way splitter in reverse to combine the signal from the 2 antennas (to maintain the correct impedance match), there will be about 3.5 dB of signal loss, about the same amount as the gain achieved by using 2 antennas. In commercial applications such as the example above, special cable harnesses called phasing harnesses are used to combine the signal from 2 antennas and maintain the correct phase relationship of the 2 signals from the 2 antennas and minimize signal loss.
 
My above RF 101 not withstanding, there is nothing wrong with a little experimentation if one is so inclined.

A two way splitter can be used in reverse and the location of each antenna/antenna spacing and the relative length of each feed line to its respective antenna can be experimental. It is possible that this might result in improved reception for certain stations of interest, although it may result in less than desirable reception, depending on local signal conditions.

One can even just connect to 2 antenna feed lines directly together and ignore the impedance mismatch and its associated signal loss (it might even be less than what results from the use of a 2 way splitter in some cases, all though the results can be difficult to predict). In this case the liberal use of RF common mode chokes on the feed lines likely would not be a bad idea.

Because of the variables involved, it is difficult to predict the resultant performance.
 
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