I'm hoping I don't have to build my own, as I can't seem to find a decent quality quadrifilar helix antenna to use for receiving 137 MHz weather fax info from polar satellites. There's ton's of information on building your own, but I was hoping to find one similar to
this one from National RF, or this
one from Time-Step in the UK.
National-RF's antenna seems to be no better than a typical homebrew, and I'm waiting to hear back from Time-Step. I think OCENS at one time offered a quad-helix as part of their weather receiver package, but I can't seem to find recent info on it.
I'm planning to use it as a backup to HF weatherfax info... I'm not ready to break out the big bucks for a satphone with data capabilities just yet!