The manuals for most Futaba radios, especially the higher end ones, certainly could be better.
Take a look here:
http://www.futaba-rc.com/faq/faq-12fg.html
And this one in particular:
http://www.futaba-rc.com/faq/faq-12fg-q959.html
This is the main FAQ page:
http://www.futaba-rc.com/faq/index.html
Hope that helps.