Posted 6/7/2006 09:03 (#17728 - in reply to #17674) Subject: RE: Trimble manual
Central Pennsylvania, USA
Ed, I think the Trimble ephemeris downloads are dated, I tried a new download and got same thing you did for AOR-W, they show it over the Atlantic but FAA says it has been over the Pacific since Feb of this year. That puts Trimble's planning software in the "Not Current" category, here at least. It makes pretty pictures but they (obviously) don't represent current status of WAAS satellite constellation and (arguably) may not represent current status of GPS satellite constellation.
Choke ring antenna's are truly great (and very costy) antenna's but I don't think the antenna that came with my EZ system is a choke ring type. Someday I will run a test of installed EZ antenna pattern, we have plenty of (steep) hills and EZ screen can (now) display roll angle and sat snr. I will drive tractor on very sloping dirt and record roll angle and AOR-W sat snr. When tractor is level, AOR-W snr is about 37 dB here now so that should give some "working range" before snr drops below data demodulation threshold. Probably need to do manual recording then post process recorded data in graphics application to display installed EZ antenna pattern. I am very curious how we can see AOR-W so well on these hills, it's elevation angle is only 11 degrees here now and some of our hills are in the 20 degree category. Only explanation that makes sense to me is that installed EZ antenna pattern has significant response for slightly negative elevation angles, maybe the test will confirm that.