[amsat-bb] Re: Quadrifilar Helix antenna question

normn3ykf at stny.rr.com normn3ykf at stny.rr.com
Sun Jan 22 18:03:45 PST 2012

Thank you for your input. I've measured 2.4:1 at it's intended design frequency, using a half wave stub. 
The antenna is essentially two loops (one capacitive and one inductive) in parallel, giving an intended 50 Ohm resistive impedance at resonance. I'm measuring 25 Ohms and a bit inductive. Do have more data if anyone is interested. (smith chart, return loss)
Tomorrow I'll build both versions, lhcp and rhcp. Tonight's live demo on so50 shows promise, though I'll need two and have to switch polarity.
73 de Norm n3ykf

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