Hi,
I’m looking for someone who did / is involved in project using Quadrifilar Helix Antenna. I have build one to pull NOAA satellite weather info but I’m a bit disappointed with the performance. I do have good background in electronics and IT but radio - that’s plumbing.
If you are doing something with software defined radio - please get in touch. I’d love to pick your mind.
Patrick.
I have a ham radio license and have played a bit with SDR.
Managed to download some images from a weather sat once, although it was tracking the satellite with a yagi: https://twitter.com/futureshape/status/762345561831968768
No experience with QFH antennas I’m afraid … but you may find a few more friendly people to ask at: https://groups.google.com/forum/#!forum/lhs-radio
Radio is an Art, IT is the plumbing ! 
Myself and the @electrotechs usually run a Thursday night electronics session. its been a bit quiet of late as we’ve all been really busy with work etc leading into Xmas but we will start again in the new year.
I have played with the NOAA weather system and it is a little flaky, especially on the antenna side and in the city. Need to make sure your getting a good match with the antenna and without a tester its a trial and error job. lots of factors at play here even down to the quality and size of the metal you make the helix out of.
Trying to think where my old NOAA radio is, will see if I can find it over the hols but it would be good to bring yours on a Thursday. The Arch from a radio perspective is very noisy and dead but that isn’t necessarily a disaster for playing with the Quadrifilar.
Courty