@kenbarbi wrote:
I've been experimenting with fractal antennas for my Lantern for several months without success until today Image may be NSFW.
Clik here to view., so haven't seen fit to report my failures in the Discussion Group.
Instead of building an L-band fractal, I decided to build an over the air (OTA) HD plane old TV (POT) fractal since they operate into the high UHF band near our beloved L-band.
From a design by William Ruckman (http://www.ruckman.net/downloads/fractaltemplate.pdf?attredirects=0) I built a working antenna using 18 gauge wire:
Front side (4 inches by 8 inches overall):
Image may be NSFW.
Clik here to view.My legs are 5/8 inch while Bill's are 1 inch. My mistake - I'll have to redo it Image may be NSFW.
Clik here to view.Reverse side with glued aluminum foil:
Image may be NSFW.
Clik here to view.I ran it up in my antenna test bed:
Image may be NSFW.
Clik here to view.And compared its reception to my Alpha Lantern sitting about 5 feet away with these results seeing 3 dB less SNR (or gain I think compared to the PATCH) than the 4 dB gain Outernet PATH antenna:
Left side IP address 192.168.0.30 is the Alpha Lantern running with a PATCH antenna, and right side IP address 192.168.0.28 is my test bed running with the Ruckman OTA/HD fractal antenna.
Now I hope I have gotten something started here. My antenna design lacks allot right now, for example, it's a 300 ohm antenna connected to a 50 ohm feed. I didn't build an antenna matcher yet, but that's to come. I'm concerned that the matcher will add too much attenuation, so am going to look at redesigning the Ruckman antenna as a 50 ohm feed, and fixing the leg length.
So folks, let's get started with Fractal Madness. Ken
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