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Fractal Antenna anyone?

"For my first effort, I laid out the bend pattern on a 1/2" thick piece of junk plywood using a 30/60 drafting triangle and a T square. At the bend points I drilled a shallow hole and inserted some small finishing nails. These were the fulcrums for the bends. As your bending proceeds, simply move the nails as appropriate.

Square the result and trim to size. Stack the four bent pieces and adjust for uniformity."

This is how I did it. Only I used roofing nails, same difference.

Dave
 
The grid is plastic. I used it because it was handy and provided some bending protection for the antenna elements once assembled.

I have built two more to spec and one other with double the dimensions. Each was mounted to a piece of wood. The "double" now feeds both my HD TV and a Yamaha 5890 through an antenna splitter. The other two service a couple of my other receivers. All with great success.
 
Voltron, have you considered doubling the number of elements, rather than doubling the size?

Dave
 
In my reception area I do just fine with the smaller version. FM reception from Mars is not one of my priorities. Build it-who knows? I would love to see a picture of a "double double".
 
Voltron said:
In my reception area I do just fine with the smaller version. FM reception from Mars is not one of my priorities. Build it-who knows? I would love to see a picture of a "double double".
Click to expand...

You may also want to try using a 1:1 current balun if your tuner has a 75 ohm input. It works a lot better for me than a 300 to 75 balun with my fractal. Mine has 3.75" long straight sections.

You can make it by taking two #24 wires, side by side, and wrapping around a ferrite core. About 10 turns works fine. The two connection on one end go to the antenna, on the other end to a 75 ohm connector.
 
Bob@FM said:
You may also want to try using a 1:1 current balun if your tuner has a 75 ohm input. It works a lot better for me than a 300 to 75 balun with my fractal. Mine has 3.75" long straight sections.

You can make it by taking two #24 wires, side by side, and wrapping around a ferrite core. About 10 turns works fine. The two connection on one end go to the antenna, on the other end to a 75 ohm connector.
Click to expand...

Hmmmm, interesting.......

Thanks,
Dave
 
Just built one for my TV using plans I found on the web. Then I thought "gee, FM?" and found this thread. Figured I'd post a pic or two as the design is a bit different and it is working very well on my TV. Picking up Boston and Rhode Island stations, 28 total but I'm going to trim out most. Only looking for the Big 3 in HD plus public TV. (Killing my Cable soon I think.)

Any way, on to the picks,

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Found the plans on a PDF in this thread:
http://www.instructables.com/id/How-to-make-a-fractal-antenna-for-HDTV-DTV-plus-/
 

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sxty8goats said:
Just built one for my TV using plans I found on the web. Then I thought "gee, FM?" and found this thread. Figured I'd post a pic or two as the design is a bit different and it is working very well on my TV. Picking up Boston and Rhode Island stations, 28 total but I'm going to trim out most. Only looking for the Big 3 in HD plus public TV.
Click to expand...

That is another form or a stacked bowtie. It is two broadband dipoles in a vertical array with a balanced feed, converted to coax with a transformer (a Balun, or Bal to unbal.)


-Gregory
 
Gregory said:
That is another form or a stacked bowtie. It is two broadband dipoles in a vertical array with a balanced feed, converted to coax with a transformer (a Balun, or Bal to unbal.)


-Gregory
Click to expand...

Ok.

It works. From what I was reading on the web, there is an increased benefit to the fractal shape of the 'bow ties'. It was fun to make. It is small and picking up all the local stations well. It sits behind my TV and can't be seen.
 
Good to hear this is working well for TV reception. I abandoned cable as well and could use a little boost on HD reception. :)
 
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