Thanks very much for the feedback everyone.
From what I was reading in the articles, I was under the impression that
a circularly polarized antenna was a step above linear polarized setups such as the Arrow (or any small yagi) and verticals. In practice, I'm having somewhat better luck with the linear setup. Until Bruce Mentioned the short yagi/tv rotator setup, I hadn't even considered my own similar setup as an option.
Here are my experiences so far:
My first attempt was with a 2m/440 mobile whip with a radial base. The antenna was tilted over about 30 degrees to be slightly more perpendicular to the predicted path of AO-51. From that pass, I could definitely tell that I was tracking a satellite, but couldn't copy anything that I was hearing. This was fed into my IC-7000 with about 15 feet of RG-8X.
Second attempt was receiving with just the 440 section of the dual moxon antenna system. The closest I got with that was perhaps a little less noise, but definitely no copy. Obviously, that's not inheriently a problem with the antenna, but likely a problem with my implementation which - which I can't really test. My antenna analyser only goes to uhf.
Bruce's email saying that a TV rotator and linear yagi's would be better than a full blown system for a beginner contradicted what I had convinced myself of - that I would be way too far down in the noise with the fact that I was linear polarized and had no elevation control, and with about 75' of less than stellar RG-58.
In fact, I have something usable right now on my roof: a cushcraft 2m/440 3 el vertical yagi on a tv rotator.
So far this has the best results to date. I've been able to copy at least parts of call signs on the latest AO-51 pass, and managed to get a pretty clear copy on a couple of CW beacon passes.
Now I'm considering incremental improvements.
I have a length of RG-213 that's been waiting to replace the radioshack RG-58 feed to the yagi, so that should give me about 2dB.
I am hearing that a preamp is an absolute requirement. I'm now researching the best method to feed the dual yagi.
If, after that, I can get a better copy on the passes, I'll try to make contact.
Thanks,
Scott NW2S