@kenbarbi wrote:
I've been experimenting with fractal antennas for my Lantern for several months without success until today
, 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):
My legs are 5/8 inch while Bill's are 1 inch. My mistake - I'll have to redo it
Reverse side with glued aluminum foil:
I ran it up in my antenna test bed:
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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