I found my old web page with graphics that shows the exact geometry of passes and elevations. See http://aprs.org/LEO-tracking.html 70% of all pass times are below 22 degrees.
After the discussion a few weeks ago, I sat down today to begin building a web page on the topic and when I went to save it, there was a page already there that I had made years ago! So there it is. Bob, Wb4aPR -----Original Message----- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Rolf Krogstad Sent: Tuesday, May 28, 2013 4:17 PM To: Bill (W1PA) Cc: amsat-bb@amsat.org Subject: [amsat-bb] Re: a cheap LEO tracker for single op Bill, You should find something in the reflector archives from 3 or 4 weeks ago where there was a discussion of what percentage of passes were overhead. It is an extremely low percentage. If I recall, most are at a an elevation of 33 degrees or less. Because of the wide beam width of my antenna, tilting the antenna at an angle of 20 to 25 degrees works well for me. I can copy the satellite beacons down to the horizon. And only on the high angle passes do I have a any drop out And because of the beam width of the antenna I don't need to keep a hand on the rotor control all the time. But it takes some practice to remember to look at the azimuth reading on the computer and to adjust the rotor accordingly every couple of minutes. The problem comes on the more overhead passes. Because the bird is closest to my location at that time it seems to accelerate as it gets overhead. On those, though, it doesn't seem to be as critical that the rotor be adjusted anywhere close to the indicated azimuth. I can hear the signal starting to fade and it is a reminder to check the azimuth. I would definitely run a number of passes with the setup before Field Day to make sure that everything works and that you can remember to do all the things that your three hands need to do during a pass! 73 from another newbie, Rolf NR0T On Tue, May 28, 2013 at 11:57 AM, Bill (W1PA) <w...@hotmail.com> wrote: > Let me ask this another way... > > Assuming minimal setup prior to each pass, can I track a LEO with a > single rotor well enough for QSO’s? (single rotor control in one > hand, VFO/Doppler on my other) > _______________________________________________ > Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
