[amsat-bb] Re: Quadrifilar Helix antenna question
mryan301 at comcast.net
Mon Jan 23 14:15:26 PST 2012
QFH are a bear to build, especially on 70 cm unless you’re very , very skilled. I tried 3 times and failed 3 times. Finally gave up and went with a standard turnstyle. Still critical tolerances but much easier to make and works lower on the horizon than the QFH. QHtenna used to sell turnstiles (reviewed in QST) but I think they are out of business now. You might also want to consider a moxon. Cebik wrote a nice article on making a moxon based turnstile. I built one for 70 cm using PVC and like the QFH and eggbeater (with reflector) , it works best on higher passes.
If you run out of patience, you might consider the Antennas.us QFH. It was also reviewed positively in QST but I don’t own one.
And lastly, omnis are small and simple, but you really need a preamp to avoid a terminal case of frustration. I use the ones from ARR with good results.
More information about the AMSAT-BB