A discussion over on QRZ.com is talking about source materials
for those new to the satellites.
As you research satellites, just make sure the source material is
dated ... and don't take as gospel anything over a year old (grin).
"Theory" and "concepts" and "modes" and "antenna theory" will not
change much over years. But when your brand new source
(either a printed book or a Web site) does not keep itself updated,
then you will run into cases of people trying to work satellites that
no longer exist.
I received an email message a year or so ago from a Boy Scout
troop master, who was disappointed that he was not able to work AO-27
and A0-51 for his kids one weekend, because the Web site from which
he downloaded information had a tutorial under the topic, "For Beginners"
that INCLUDED working '27 and '51.
Unfortunately, those satellites both have been "dead" for several years ...
So, as you wander the 'Net for information, look for "Last Updated" notations.
And look for those who post contact info for quick answers. And/or support
messageboards. Heck, a site or two even offer dedicated telephone lines for
urgent (or non-urgent!) requests.
It is the beauty of the Internet that so much information can be made available.
Unfortunately for those using the 'Net, many authors do not update their once-
wonderful articles ... or Webmasters many times post an article, then never follow
with updated info or publishing "addendums" to their works. Finding DATED info
may take a little more time - but will result in less frustration!