Introduction: How to Make a Fractal Antenna for HDTV / DTV Plus More on the Cheap

Picture of How to Make a Fractal Antenna for HDTV / DTV Plus More on the Cheap

This instructable is from:

and submitted by William Ruckman of

Showcased in the March 2015 issue of Popular Science Magazine:

The first thing I would like to discuss is a little history, theory, and uses for fractal antennas.

Fractal antennas are a recent discovery. First discovered back in 1988 by Nathan Cohen and later published and patented in 1995. A fractal antenna has a few unique attributes as seen in this definition from Wikipedia:

"A fractal antenna is an antenna that uses a fractal, self-similar design to maximize the length, or increase the perimeter (on inside sections or the outer structure), of material that can receive or transmit electromagnetic signals within a given total surface area or volume."

What exactly does that mean? Well, you need to know what a fractal is. Also from Wikipedia:

"A fractal is generally a rough or fragmented geometric shape that can be split into parts, each of which is (at least approximately) a reduced-size copy of the whole,a property called self-similarity."

So basically, a fractal is a geometric shape that repeats and appears over and over no matter how far out or how far in you zoom magnification.

Source: Wikipedia and Patent number: 7088965]

Fractal antennas have been found to be approximately 20% more efficient than normal antennas. Which could be useful. Especially if you want to make your own TV antenna to pick up over the air digital or high definition video, increase your cellular range, wifi range, FM or AM radio reception, and so on. Most cell phones already have built in fractal antennas. If you noticed in the past few years that cell phones no longer have antennas on the outside. That is because they have a internal fractal antenna etched on a circuit board which allows them to get better reception and pick up more frequencies such as bluetooth, cellular, and WIFI all from one antenna at the same time!

Wikipedia info:

"A fractal antenna's response differs markedly from traditional antenna designs, in that it is capable of operating with good-to-excellent performance at many different frequencies simultaneously. Normally standard antennas have to be "cut" for the frequency for which they are to be usedand thus the standard antennas only work well at that frequency. This makes the fractal antenna an excellent design for wideband and multiband applications."

The trick is to design your fractal antenna to resonate at what ever center frequency you wish to receive. Which means it will look different and be sized different depending on what you want to receive. A little math can be used to figure this out. (Or a online calculator)

In my example, I am going to make a simple one but you may want to make a more elaborate one. The more elaborate the better. I will use a spool of 18 Gauge solid core wire to make a antenna as an example but you could go as far as to etch your own circuit boards for aesthetic reasons, to make it smaller, or more elaborate with more resolution and resonance.

I am going to use the example of making a TV antenna for digital or high definition reception for over the air broadcasts. It is easier to work with these frequencies and they fall around half a foot to a few feet in length for half wavelengths of the signal. I am also going to base it off a common dipole antenna for simplicity and cheapness of parts for VHF. For UHF you may want to add a director or reflector which will also make it more direction dependent. VHF is direction dependent as well but instead of pointing directly at the TV station like UHF you want VHF rabbit ears (dipole antenna) to be perpendicular to the TV station. But there is a little more design to that. I want to keep this as simple as possible as it is already a very complex subject.

Basic supplies (cost me about $15):

Mounting surface such as the plastic project enclosure (8"x6"x3").
6 screws. I used steel self tapping sheet metal screws.
A impedance matching transformer 300 ohm to 75 ohm.
Some 18 gauge solid hook up wire.
RG-6 coaxial with terminators (and rubber jacket if mounting outside).
Aluminum if using a reflector. The enclosure above came with one.
A sharpie marker or equivalent preferably with a fine tip.
Two pairs of small needle nose pliers.
A ruler of at least 8 inches.
A protractor to measure angle.
A drill and drill bit that is smaller diameter than your screws.
Small wire cutter.
Screw driver or screw gun.

NOTE: The bottom of the antenna is to the right of this picture where the transformer sticks out.

Step 1: Adding the Reflector

Picture of Adding the Reflector

Assemble the enclosure with the reflector under the plastic cover.

Step 2: Drill Holes and Add Mounting Points

Picture of Drill Holes and Add Mounting Points

Drill small tap holes on the opposite side from the reflector in the following positions and place a conductive screw.

Step 3: Measure, Cut, and Strip Wire

Picture of Measure, Cut, and Strip Wire

Cut four 8" pieces of the solid core wire and strip it bare.

Step 4: Measure and Mark Wire

Picture of Measure and Mark Wire

Use a marker and mark every 1" on the wire. (This is where we are going to make the bends)

Step 5: Create Fractals

Picture of Create Fractals

You will repeat this step for each wire. Each bend on the wire will be 60 degrees exactly as we will be making equilateral triangles with this fractal. I used two pairs of pliers and a protractor. Each bend will be made at the 1 marks. Make sure you visualize the direction of each bend first before making it! Use the diagram below to help.

Step 6: Create Dipoles

Picture of Create Dipoles

Cut 2 more pieces of wire at least 6 inches long and strip them. Bend these wires around the top and bottom screws going longways and contact the center screws. So all three are contacted. Use the wire cutter and trim unneeded wire.

Step 7: Mount Dipoles and Mount Transformer

Picture of Mount Dipoles and Mount Transformer

Place and screw down each of your fractals to the corner screws.

Attach the impedance matching transformer across the two center screws and tighten them down.

BUILD COMPLETE! Test and enjoy!

Step 8: Testing Verses Store Bought Antenna

Picture of Testing Verses Store Bought Antenna

To see the results of the tests I ran click the link below:


Step 9: More Iterations / Experimentation

Picture of More Iterations / Experimentation

I have made some new elements using a paper template I made in Gimp (photo editor). I used small solid core wire from telephone wire and it was solid enough, small enough, and malleable enough to bend into the intricate shape required at the selected center frequency (554Mhz - as this is the mean of the digital UHF over the air TV channels in my area) and iteration of the chosen fractal design. Which is repeated triangles.

Photo attached. It may be hard to see with the photo taken in low light, the color of the cardboard, and the color of the copper with tape over it to hold it in place. But you get the idea.

At that size the elements are pretty fragile, so they have to be handled carefully.

I have also attached the template in png format. For it to print the proper size, you have to open it in a photo editor like Gimp. The template isn't perfect as i made it by hand with a mouse, but it is close enough for human hands and a needle nose for bending of the elements.



williamruckman (author)2013-01-22

I have made some new elements using a paper template I made in Gimp (photo editor). I used small solid core wire from telephone wire and it was solid enough, small enough, and malleable enough to bend into the intricate shape required at the selected center frequency (554Mhz - as this is the mean of the digital UHF over the air TV channels in my area) and iteration of the chosen fractal design. Which is repeated triangles.

Photo attached. It may be hard to see with the photo taken in low light, the color of the cardboard, and the color of the copper with tape over it to hold it in place. But you get the idea.

At that size the elements are pretty fragile, so they have to be handled carefully.

I have also attached the template in png format. For it to print the proper size, you have to open it in a photo editor like Gimp. The template isn't perfect as i made it by hand with a mouse, but it is close enough for human hands and a needle nose for bending of the elements.


tg5690 made it! (author)2015-08-19

Understand this is an older project, but it was exactly what was required as it was time to cut the cable cord. Not only used parts of this plan but also incorporated the best of similar designs out there. I'm no expert, but have done enough tech builds to get the feel of what looks important in other designs. Ended up with a hybrid design that used both the small and large fractal shapes plus two sets of bow ties. Added the reflector and it works great! The big change in my shapes is that I filled in more of the interior so as to capture more signal with more surface area in my elements. Made a jig to help in the bending process - but with 8 gauge wire it was a tough process. Made it through with vise grips and pliers. Probably made some mistakes, but it works. Thanks to all who shared their hard work so the rest of us could copy and have fun with it.

tg5690 (author)tg56902015-08-19

By the way, getting consistently great results from towers about 30-60 miles away and when the atmosphere is cooperating, actually got signals from about 200 miles away. This last only happens occasionally and not the normal performance of this design. Not bad for an attic mount. Since this is feeding multiple TVs, added a amplified splitter to compensate. In my initial tests without an amp, this fed 1 TV a strong signal on its own and got the occasional distant signals without the amp as well.

tg5690 (author)tg56902015-08-20

A few things other designers thought was important:

The moisture in wood conducts electricity so the main upright in this build is leftover decking material that is more plastic than wood fiber. Thought about some PVC lumber, but that stuff is expensive!

Another plan thought it important to maintain the spacing of the phase lines when they cross. My plan has half inch stand offs for the phase lines and a full one inch spacer where they cross. One line goes over and the other under to maintain that distance and presumably cuts some crosstalk.

One designer wanted 9 1/2 inches between the main elements, but I opted for 8 as my attic is a bit cramped for vertical space.

Read where different lengths of elements were better at different frequencies. I did not do much of the math. Frankly this build was more for fun and experimentation. Instead I decided to go with the hybrid approach as that would give me three very different lengths for the elements. I hoped that would provide a good range of frequencies. The lowest channel I get is 8 and have seen channel 61 on those rare nights when long distance signals come in.

Decided to use small carriage bolts to secure the elements to the phase lines.

If this were to be used outside, probably best to use aluminum and PVC for the framework as the wind would catch this and tear it up!

Drilled a hole so I could put the balun on the back. Don't know if this helps anything,but it allowed me to put a short coax line between the balun and the amplified splitter and mount the splitter on the back of the reflector.

tg5690 (author)tg56902015-08-30

One more thing. Most plans that specified reflectors indicated the optimum distance between the elements and the reflector was 5 1/2 inches. Note: Reflectors make antennas highly directional, so try your build without the reflector first to find out if it is truly necessary. I used hardware cloth but others use aluminum foil, metal cooking grates, and thicker bar stock for the reflector material. The purpose of the reflector is to increase the signal strength so if your build needs just a bit more signal to clear up certain stations, this may be just the ticket. Also since the reflector makes the antenna directional you might need one if you live in an area where co-channel or adjacent channel interference is an issue. In my case, we have some adjacent channel interference between channels 30 and 31. Since both towers are both in the same direction, my reflector cannot assist and block one. Wonder why the FCC allowed this issue?

tg5690 (author)tg56902015-11-20

Recently added some aluminum foil on the reflector and it helped clean up some long distance and low power signals. Still have some issues with other low power signals, so I am planning to make another unit with a similar design but using 8 of the complex big fractal shapes. May end up ganging the two together like an 8 bay bow tie just to see what will happen. What I have now works fine for the majority of stations within 60 miles, but would like to pull in the low power stations if I can.

tg5690 made it! (author)tg56902016-04-14

After using my original design for some months found that some of the lower power signals just were not coming in as well as hoped, so decided to do a new build and gang them together like some 8 bay antennas seen online. Results have been interesting. Most station signals show significant improvement in strength, but one signal shows little improvement, and is even worse at times. Been tweaking the direction of the antenna and have gotten to a setup that works for the time being.

The new half of the expanded antenna now uses more of the fractal stars, but using 10 gauge wire instead of 8. The thinner wire allowed for quicker bending in my template jig and much less hand pain overall. Since there were 4 pairs of the larger fractal shapes, the overall length of the build was 38". Using an amplified distribution splitter at the antenna allows for most signals to report at 100% strength on most of my TVs. Again, better results for most signals, save one. Guess if a signal is too weak, even a bigger antenna will not always help.

Still, pleased with my build and enjoying throwing away all the ads from the cable company since cutting the cord!

tg5690 (author)tg56902016-04-16

After a few more tweaks, have managed to get the one problem low power signal coming in as well as before. The signal is just too weak and too far away to get much better. Did a few changes to the original half of the antenna to make it better match the new half. Wanted as balanced a construction as possible. Again, pleased with the overall improvement in the signal strength for most of the strong and medium power signals.

tg5690 (author)tg56902017-02-16

A recent addition to my system was a dedicated amplifier with an LTE and FM band filter. This more than anything has helped with the drop outs (mostly audio drop outs) I was experiencing on a few channels. Understand this issue is common when amplifying OTA signals for distribution to multiple TVs. Regular amps also amplify interference caused by certain cell phone and FM radio frequencies. Got my amp/filter from Channel Master, the company that also made my DVR of choice.

kevincarruthers (author)tg56902015-08-20

Can i see a bigger picture of your build ? I am trying to design an antenna that reaches at least 80 miles

tg5690 made it! (author)kevincarruthers2015-08-20

Here is a picture without the reflector. Hope this helps.

tg5690 made it! (author)tg56902015-08-20

Here are the templates I used for the jigs. Each segment is one inch.

M_P_Hawes made it! (author)2016-11-13

Here is a pic of my experimental build with cardboard and the use of a glue gun. You will notice a few things that I did and may have an impact on my build:

1. For the joining wires - I did a "V" type joint. My thinking was I get a higher point of contact with the aerial. The downside is I'm not connected at the end point of the aerial but 3/8 to 1/2 inch on each side of the aerial. This may have no impact, may give me more or may give me less signal. This has to be tested.
2. The crossing points for the joining wires - there is a 1/2 gap between the white and black wire. I used 14 gauge electrical wire for it is flexable enough to use and is strong enough to hold it's shape.
3. I pinned down each aerial with the glue gun to keep the aerials in place.
4. The impedance matching transformer is on the backside of the board to help prevent interferance.

M_P_Hawes (author)2016-11-13

A few more things to note that will help:
1. I like to use PVC pipe in my builds. The reason being is it's cheap, it can be bent if needed by a heat gun or even a hair dryer in a pinch, and is non conductive.
2. A hot glue gun is a nice to have when putting things together. I believe screws that hold down aerials change the way the signal is captured for it adds metal to the shape of the aerial. In my last build I used the hot glue gun to glue my connections together. This worked really well. I did an experimental build with cardboard to see how this would work and I was really pleased with the results.
3. Line of site is best when positioning your antenna.
4. Use high quality coax and pick the best for the job. Look here on what to select:

5. Signal strength monitor - I have a USB digital TV adapter for my laptop. There is software you can use with them to measure signal strength. For example this one:

6. if you have old RG-59 coax and you have a mess of wires in the back of your TV, this will cause a loss of signal due to noise the other wires generate.
7. Dimmer switches that are on the same circuit as the TV are big causes of signal noise and can cause a lose of signal for the antenna.
8. When hooking up the impedance matching transformer to your antenna, it is best to have it at a 90 degree angle to the vertical plane of the antenna (put it in horizontal, having it go straight back ) so that when the coax cable is connected to it the coax is well away from the aerials. Otherwise you run the risk of the coax interfering with the aerials capturing the broadcast signal. You will see this setup on pretty much every store bought antenna.
9. As I said in my other post - you can combine antennas just as long as the coax from each antenna to the junction point is the same length. If you need to build several directional antennas to capture weak signals from distance towers - make sure the antennas are at least 2 feet apart when it comes to the reflector on the antenna. You may be able to put them closer but at the time of this writing I have not tested this. I plan to see if I can build a long range antenna to test. Should be fun.
10. The coax will require a 7/16 wrench. Make sure you have two wrenches.
11. Before hooking to the TV, look to see if the coax plug on the TV has a capture nut on it. If yes, make sure it is snug but DO NOT OVER TIGHTEN. You will break the plug if you over tighten. If you break it you may be able to solder a replacement connection but most likely you will have to replace the board the connector is soldered to inside the TV. (Been there, got the t-shirt - did it on my booster)
12. If you are a old gamer like me you may have a NES. The NES coax connector will cause a lose of signal. I even tried a booster to get around that. Nope. You have to hook up the NES using the RCA connectors.
13. I tried using a jig to bend the wire when making an aerial. I found it made for round corners that needed to be tweaked and it made the straight sections not so straight.
14. Some folks will let the aerials be free standing in that they are only connected at the joining wire point. You "can" do this but be warned - if the angles of the bends in the aerials change at all you WILL lose signal. In my builds I like to draw the pattern on the backing material that the aerial is attached to and use my glue gun to make sure the aerial is exactly in the right place. This makes a huge difference in my opinion in signal gain.
15. Aerial stack - in some long rang antennas I've seen a stack of small aerials in front of a reflector. I plan to use this concept in a future build to see if a fractal setup in a stack in front of a reflector would bring in weak signals better without a booster.

M_P_Hawes (author)2016-11-12

I've been reading everything in this thread and I've learned a few things that will help:

1. When making the bends in the wire for the aerials - the corners need to be sharp as possible. Rounded bends in the fractal aerial reduce signal.
2. In between each bend for the wire for the aerials - the wire needs to be as straight as possible. - this increases signal.
3. You CAN combine several antennas together to increase signal. The things to remember is the wires coming from the different antennas need to be the same length to the junction point. Otherwise you get ghosting. I have a 4 antenna setup for my living room TV that works perfectly using this principle.
4. The cable length from the antenna should NOT have bends in it if at all possible. Any bends cause a loss of signal.
5. The cable length from the antenna to the TV should be as short as possible. Longer cable equals more signal loss.
6. It is possible to make a fractal aerial setup omni-directional. In a 4 pair fractal setup - I took and pivoted each pair in the stack by 15 degrees. I then combined several antennas together so I had fractal pairs pointing in every direction. This setup worked extremely well.
7. The higher the antenna, the more signal you get but only to a point and then only diminishing returns on any further gains.
8. If you use a antenna that is outside - it is critical the antenna is grounded and has a surge protector to protect from lightening strikes.
9. Home run (one continuous line) the line from the antenna to the TV if possible. Each additional junction, even a barrel connector will cause a loss of signal.
10. Elbow connectors - they cause a loss of signal. I've tried a couple of brands and they all caused a loss of signal.
11. Anything metal usually deflects and reflects signal. Things in your home like wires in the walls, appliances, duct work - they all will change the way the signal reaches the antenna or block it.
12. Don't use cardboard in making an antenna. It will seem to work well at first but the cardboard is really just paper and sooner or later - the cardboard will warp. I discovered this with an antenna I made and put in my attic. It was warped something terrible after only a few days.
13. Spend the money on quality coax connectors. The cheap ones are simply that cheap and you lose signal. Harbor freight sells a crimper for the quality coax connectors that is around 20$. That may seem a lot but I've seen them go for much more. They also throw in a few coax connectors in the box and they normally got for about a dollar a piece.
14. Do the math on figuring out the best type of fractal antenna will work for you. Look at the channels you should get, and how far away they are from you. The links on this thread on doing this are very helpful.
15. For the wires that link the Fractal aerials and if they cross (in a 4 pair setup for example) - there HAS to be a 1/2 gap where the wires cross. Put in a spacer so the wires stay apart. You will notice on the impedance matching transformer 300 ohm to 75 ohm the two wires coming out of it have a gap between them. That is there for a reason. If they get closer together - you lose signal.

With all the things above and if you are careful - you will build an antenna that will give you a much higher signal than one that is poorly made. I've made about a dozen antennas now and I'm finding doing all these little things add up in getting more channels, more stable signal, and less messing with having to do things like rotating the antenna to pick up the channel you want.
Happy building!

AhmedH256 (author)2016-10-26

will it work if I connect the transformer to a 50 ohm coax?

JohnB605 (author)2016-04-27

Made this antenna 1st try was able to get 4 stations reliably. Did a search for the following had an example I tried to follow.

How do you determine the length of an antenna and the size of a fractal antenna?

Found my frequencies for my area averaged the used the above search result converted to inch

Made a 2nd set of fractals using 4-5/16" wire instead of 8" much smaller but picked up 2 more stations. Now have main network stations OTA.

Thanks for the info, plan to make 2 more for sons who view TV online Hulu and Netflix

wipedaler made it! (author)2015-12-13

I made the fractal antenna this evening, using coat hanger wire mounted to a small piece of polycarbonate. To simplify the straight sections, I cut a straight wire with short legs on each end, bent to match up with the base of each 'star'. Each straight connector was soldered to the apex of two stars, and I added a small loop at the midpoint to accept a mounting screw thru from the back. The screw was long enough for a second nut to secure the adapter.

The unit works very well; it's lying flat on top of a kitchen cabinet, and pulls in as many channels as a 'whisker' antenna used to feed two other TVs.

Thank you for the example JPG. I had to print it at ~110% to get near true scale.

[Next attempt at this plan will be to use 18-gauge wire laid onto and sandwiched between the sticky, clear carpet protector film that builders and realtors use. Once wired and tested, I'll simply transfer it onto one half of a sheet, and then fold over the other half to make a sticky antenna sandwich.]

Taw SernT (author)2015-10-25


Sorry, I have dug up this old post. I am interested in making a Antenna for my new TV to receive digital TV signal.

I have some questions on the material:

1) What will the different effect of I use different material, say, steel, copper, and aluminum?

2) What will be the effect of width/thickness of the wire?

3) Must the wire in the antenna be bare? Can I let it in the insulator?

4) Can I use stranded wire? What is the effect?

5) I have an old "V" shaped antenna (rabbit ear?), can I just use the matching transformer here?

6) I have another old flexible antenna (I cannot remember the name for this), can I make it into a Fractal Antnna?

7) What do you think of the effect of this antenna:

Attached are the 2 antennas that I mentioned in (5) and (6).

kevincarruthers made it! (author)2015-08-23

I kept mine the same size as my whisker antenna to compare them. This antenna does have better reception and it is only about 1/2 as wide as my other. As for bending the stars I simply made a pattern and used finishing nails on the corners to bend the wires. He bought antenna I have received 2 channels and this one receives all 8 of my local channels including ch10 (192mhz) 30 miles away. Now I'm trying to get the next station at 60 miles. Thanks for posting this and thanks to tg5690 for sharing your pic, I will be using some of it in my next build

kevincarruthers (author)2015-08-16

I recently built a 4 DP "whisker" antenna and it works better than expected, I can reach about 30 mi with it. It does currently get ch 10 (192 mhz) which is the local channel for us so I need to be able to get it. Now my question is this- the whiskers are 10" long so each wire is cut at 20" and bent to give me about 4" between each whisker tip. When I design my fractal antenna would I still cut the wires at 20" and bend them or does the fractal design create a longer wavelength because of all the bends? Also would I keep the closest points of the fractal antenna 4" apart? I tried using the antenna analyzing tool MMANA-GAL but as I am new to this I don't know how to use it properly

williamruckman (author)2015-07-21

Hello Everyone! I just wanted to drop in and let you all know a few things that happened with the project recently. I have attached a picture of a build I did on Plexiglas which is one more iteration smaller.

Also, this antenna was showcased in the March 2015 issue of Popular Science:

There are some more things in the making, but i will hit you with them when it is a reality!

Let's keep the wonderful collaboration going! I can't wait to see more of your designs!

gerry1946 (author)2012-10-06

OK I'll try this again.

I built the fractal antenna shown in the attached picture. Works great. I am 35 miles south of Milwaukee, WI and I receive 20 - 30 stations clearly. I can get Chicago stations but I must rotate the antenna.

Please comment on the circular design that I plan to build. Will it work if there are 20 fractals on the large diameter and only 11 on the small diameter. The large circle is 20 inches in diameter. The small circle is 18 inches in diameter. The fractals are approximately 3 inches tall.

Thanks for posting you instructions for the fractal antenna. Much better than my V shaped coat hanger design.

Sorry if I get multiple images. ??????

ku5e (author)gerry19462015-03-25

You want to design Antennas, I suggest you use a program like, MMANA-GAL to simulate it before you build it.
A couple of observations on your idea.
1. You have to be careful with the feedpoint impedance. Your TV equipment uses 75 Ohms. Most antennas, like the fractal and loop antenna I posted above will have a 300 Ohm feedpoint. This is the reason we use the adapter. More specifically a BalUn. In this case a 4:1 BalUn to convert 300 to 75.
2. Your design assumes that the feedpoint will be 75 Ohms, I guarantee it will not be. This is why you have to simulate it before you build it.
3. Antennas want to be balanced (in most cases), your design will be imbalanced so the feed point will have to be moved to achieve balance or a suitable feedpoint impedance.
If there is an impedance mismatch (antenna to receiver) the amount of signal present at the TV will be much lower.
For example if you connect the 75 Ohm coax directly to the feedpoint of the fractal antenna I posted (which has a 300 ohm impedance) you would experience 4.087 db loss. Every 3 dbs of loss is a halfing of the signal. Therefore, you would loose more than half your signal.
I hope this helps.

ghz24 (author)ku5e2015-07-13

Your statements are correct, but your math is wrong.

75 vs 300 ohms gives a SWR of 4 and a miss match loss of ~1.9 dB.

A SWR of 8 gives the ~4 dB loss you stated.

A point you didn't cover is that SWR of greater than 3 can interfere with the tuners ability to decode the digital symbols and resulting in a much higher apparent signal loss (signal quality ).

You are absolutely right about modeling and simulations.

AdrianC13 (author)ku5e2015-05-22


I was wondering if you could help me out with a few doubts I have.

1. Is the design (like for example the one in this instructable) dependent on the location (city/country/continent)?

2. If it is, what details do I need to find out in order to design an efficient "HD" antenna (transmitted frequencies or other stuff maybe)? If so, any suggestions on how to look them up?

3. Do I need a BalUn regardless of the design of the fractal/antenna I make or is the design dictating if I really need it? I ask cause I found a "box" design in youtube where they basically just stapled the narrow end of the antenna to the coaxial, no balun, but then you mentioned that most antennas will need it.

Thank in advance for your help! :D

gerry.friso (author)ku5e2015-03-26

Thanks for your comments. I have moved on from the circular design. It did not work as well as the rectangular design. I built a larger (More Fractals) antenna which worked quite well but it was large and not very attractive.

ku5e (author)gerry.friso2015-03-26

Gerry, I am a HAM radio Extra class operator, and have studied antenna design a lot. My hobby relies on it very much. One thing that is not mentioned in this instructable, partly because it is out of the scope of it, is that even number of elements tend to work better. Keep that in mind when creating antennas. Also when you have stacked elements it is a good idea to have half of them out of phase to the others.
What this means is that if you call one wire A and the other B, have A going to the left side of two elements and then to the right side of the other 2 elements. You can see this in the design I posted a few days ago in this forum. Good luck and have fun experimenting. That is what it is all about!

gemluvr (author)gerry19462014-08-05

The circular fractal antenna that you have showing in a diagram - did you make it yet? How did that work out?

chuckr44 (author)2015-03-03

Can't you paint this shape using liquid conductive paste?

ku5e (author)chuckr442015-03-25

You could, but it would be very thin. The thiness might limit the antennas bandwidth (frequency range). This antenna needs to receive from (470-698 Mhz) which is pretty wide.

ku5e made it! (author)2015-03-25

Here is my version 8 elements. After building it I found that I had poor reception in the HI-VHF (7-13 {174-216 Mhz} area. While there are not that many DTV channels that use this range, here in Orlando, Fl, one of the major channels is Channel 2 and it uses DTV Channel 11 (198-204 Mhz). The frequency is not quite UHF, in fact it is very much VHF. This Fractal antenna is designed as a great performer in the UHF range (470-698 Mhz), but not so much n the lower frequency range.
In order to remedy this I added a full wave loop designed around 195 Mhz, which also the center frequency of the HI-VHF range. I then connected it to the end of the phase lines. This works because at UHF frequencies the loops impedance is so high it does not effect (much) the UHF part of the antenna. And the same is true for the UHF's section impedance when using VHF frequencies.
I put it together and tested it and all the channels listed on were viewable.
This antenna works almost as good as the huge Grey-Hoverman/Cat Whisters I presently use.
Pictures attached.
1. Antenna on my jig board
2. My design on paper with loop dimensions
3. My Cat Whisker Antenna

AnithaG1 (author)2014-12-02

hi friends,

Am going to do research in fractal antenna can anybody say what recent problem in fractal antenna? and how to find recent problems in fractal microstrip patch antenna?

davidbarcomb (author)2014-11-23

Very nice instructable, clear and concise.

AaronW3 (author)2014-10-31

I got a 6' coax for $4 and the transformer for $3 off of ebay, both shipping quickly from the US.

JeypiB (author)2014-09-18

I'm late reading this blog but I find it a good and helpful. I cant wait to do this It is a good thing I've read this <a href="">How to Install Antenna</a! I can't wait to do this!

burnerjack01 (author)2014-09-14

Making a jig on a board using small nails or screws would make this go very quick and very repeatable. I can't wait to do this!

gemluvr (author)2014-06-22

Holy CRAP! This is COOL!!! I want to try and make this stuff! I'm finding it's answering questions I've had when reading all the posts. This is GOOD!!!

MrEggsalad made it! (author)2014-02-16

I took some copper wire and an old coat hanger to create my fractal antenna. It works really well, certainly far better than a standard ~$15 antenna and references suggest it works as well as the best of indoor antennas and even a decent amount of outdoor antennas. I did notice that initially my reception was lower than anticipated, but I upgraded the cable used to connect the antenna to my TV and that fixed those problems which were likely due to poorly shielded cables.

Dalmo (author)2013-07-04

Hy guys! May I do the Fractals with 12AWG wire? Because this wire we have!

SpikeG79 (author)2013-06-10

Just made 2 of these 'fractal stars' design that is in ToriAmos' post to add to my original Ruckman design antenna and gained about 5-10% signal strength on all channels. Very impressed :). I added them to the screws that held the transformer terminals. The 5 major network channels now come in @ 80-100% from 70-90%. One new local lower powered station strength went from 50% - 65-70% and is now watchable. I made them with 20 inch lengths of coat hanger wire so there's about 1/2 inch between bends, they take up about 5 inch x 5 inch square area. If I would have made them 10"x10" square area you would need about 40 inches of wire and 1 inch between bends. Hope this info helps.

SpeakerBoy (author)2013-03-26

I've made a version of this using ¼" adhesive-backed copper foil tape (the kind used by stained-glass hobbyists) applied to a sheet of acrylic, (without a reflector) and the results were both beautiful (think "Copper Snowflake Sun-Catcher") and impressive. By printing out your template and lining it up with match lines I put on the backside of the acrylic sheet, I was able to apply my strips of foil directly over it in the appropriate places. The adhesive is NOT conductive, but a few well-placed needle pricks soon cured that problem. Once I found the "sweet spot" in my bedroom window, it was performing just as well as my Gray-Hoverman (with reflectors!) while taking up a fraction of the space. It's an elegant little solution for apartment dwellers! I can't thank you enough!

jschwab (author)2011-03-14

I've modified the design to increase fractals, adding another set of fractal "whiskers" giving 3 sets per side and iterating the fractal shape several more times, while still fitting into the same compact space.

bending the wires is a little time consuming, but in theory it should add more stable reception. i thought it might be helpful if anyone else was curious about increasing the fractal bends.

Attached here is a pdf for use as a guide / template.

Also, this can easily be mounted to cardboard, pexiglass etc and placed INSIDE the project box, to conceal the antenna.

moffett8 (author)jschwab2013-02-25

On the 2nd design fractal antenna. The distance between the bends is much less that the 1" on the 1st design. What should the distance between the bends be on the 2nd antenna?


ToriAmos (author)jschwab2012-11-02

Are there a couple of segments missing from the free end of each loop? It seems like there should be 5 small identical loops within each main loop. I have a modified version and would really appreciate it if someone could tell me if I have done it right.

Lee_Smith (author)jschwab2012-06-05

for this design do you use all 6 fractals or could you use four like in this ible?

festizio (author)jschwab2012-03-05

At what size should I print this template to achieve the same center channel as the one from the main instructable?

jschwab (author)festizio2012-03-05

I printed mine at the default printer setting for a full 8.5 x 11 page. hope this helps.

festizio (author)jschwab2012-03-05

So, does the image take up the whole page?

jschwab (author)festizio2012-03-06

If you print with no scaling it should take up a little more than half the page. mine came out centered on the sheet of paper, with the longest edge measuring around 6 inches.

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