Online real-time satellite tracking:
• N2YO http://www.n2yo.com/
Online orbital predictions
• AMSAT-NA http://www.amsat.org/track/
• AMSAT-LU http://amsat.org.ar/pass.htm
Free PC satellite tracking Apps include:
• Gpredict http://gpredict.oz9aec.net/
• Orbitron http://www.stoff.pl/
Free mobile satellite tracking Apps include:
• iOS iPhone/iPad Satellite Explorer Pro https://itunes.apple.com/us/app/satellite-explorer-pro/id669039200?mt=8
• Windows Satellite Explorer https://www.microsoft.com/en-us/store/apps/satellite-explorer/9wzdncrdfqx1
• Android AmsatDroid Free http://www.amazon.com/G4DPZ-AmsatDroid-Free/dp/B00DK7XXYK/
Keplerian elements (‘Keps’) provide a mathematical description of a Satellite’s orbit. Satellite tracking software reads the Keplerian elements and provides graphical and/or tabular orbital predictions. Keplerian data are most commonly provided in the AMSAT and the Space Command / NASA Two-Line Element (TLE) format. You can also use the “kep-char” Excel spreadsheet to determine orbital characteristics of a set of Keplerian elements.
The North American Aerospace Defence Command (NORAD) Two-Line Element Set Format http://celestrak.com/NORAD/documentation/tle-fmt.asp
Keplerian Two Line Elements (TLEs) ‘Keps’:
• New satellites launched in past 30 days http://celestrak.com/NORAD/elements/tle-new.txt
• CubeSats http://celestrak.com/NORAD/elements/cubesat.txt
• Experimental satellites http://celestrak.com/NORAD/elements/x-comm.txt
• Engineering satellites http://celestrak.com/NORAD/elements/engineering.txt
• Amateur radio satellites http://www.amsat.org/amsat/ftp/keps/current/nasa.all
Adding new satellites to SatPC32, Gpredict and Nova
http://amsat-uk.org/2013/11/23/adding-new-satellites-to-satpc32/
A directional satellite tracking antenna can be made using just a small Yagi and a TV antenna rotator. Bob Bruninga WB4APR suggests fixing the Yagi to point 15 degrees above the horizon to produce good results for both satellite and terrestrial working. Read Bob’s article at http://aprs.org/LEO-tracking.html
Doppler Shift
Bringing the One True Rule of Doppler Tuning into the 21st Century
http://www.amsat.org/wordpress/wp-content/uploads/2015/02/FDT-WA4SCA.pdf
The One True Rule for Doppler Tuning 1994
https://web.archive.org/web/20070202134146/http://www.amsat.org/amsat/features/one_true_rule.html
Application of Amateur Radio in Geophysics: Calculation of a Satellite’s Orbital Velocity from Doppler Frequency Shift by Dr. Carol F. Milazzo, KP4MD http://www.qsl.net/kp4md/doppler.htm
NASA Orbital Lifetime Software http://orbitaldebris.jsc.nasa.gov/mitigate/das.html