Amsat.org is the website of the Radio Amateur Satellite Corporation (AMSAT), an organization which works since 1969.
It is actually an educational corporation, which was founded to continue the efforts, begun in 1961, by Project OSCAR, a west coast USA-based group which built and launched the very first Amateur Radio satellite, OSCAR. Though the corporation is fond of traditions, its designs and technology continue to push the outside of the envelope. For over 39 years AMSAT groups in North America and elsewhere have played a key role in significantly advancing the state of the art in space science, space education, and space technology. Its site is aimed to contribute the corporation’s work, by offering much information about the activities and achievements of the organization. Check the different sections above, which include navigator, Keplerian elements, passes, news, and also an online store. There are many downloadable archives available, in .pdf and other extensions. 
