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MOBIUS cross loop antenna - Printable Version

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MOBIUS cross loop antenna - radiofarol - 2017-06-03

Hi all
I`m a new participant and I had running the system blue, first with two 200mm indoor rod ferrite antenna, that later I changed to MOBIUS cross loop. The system seems working very well with ferrite antennas, but it pickup strong noise from switching power supply in my house and Neighbors (I live in an apartment), especially from cell phone chargers. So I build a cross MOBIUS loop with coaxial cable HELIAX 3/8", with PL 259 connectores, and respective SO panel connector. I used a square metal box for coaxial connectors, that shunt all shields in the point oposite to the inverter connections of the coaxial cable. I had run this antenna for some days, and it working great, with much lower noise and more directivity that give the possibility of optimizing the noise floor. With this "shield shunted" MOBIUS cross loop I was able to detect lightning at 6600Km. I read about MOBIUS and I always saw that the shields were not interconnected. So, I decided buil a new "shield isolated" MOBIUS cross loop and test again. I was desapointed, because the noise go up and the directivity drop. I tested this "isolated loops" by a pair of days, and the detection drop a lot. Again, I returned to the "Shield shunted" cross loop, and the detections ratio was go up again. I use a gray color toroid transformer with 50 turns of 0.25 isolated wire.  Has someone  done other tests with MOBIUS cross loop?