[nash]

A nice site that explains the workings of a typical AA5 set in detail is http://www.angelfire.com/electronic/funw...AA5-1.html

Many problems with radios are due to failed capacitors. A good reference site on replacing capacitors, identifying, reading values, etc. is http://www.antiqueradio.org/recap.htm

Tube sockets are read looking at the bottom of the socket (under the chassis), counting clockwise from the right of the key, with the key at the top. The key is the gap between pins in 7 and 9 pin miniature tubes, the tab on octals and loctals, or the two large pins on older 6 pin tubes.

There are several good tube databases online for looking up tube specifications and pinouts. http://scottbecker.net/tube/index.html and http://70.167.193.117/Common/Tube/Excel/Tube.php

For schematics Nostalgia air http://www.nostalgiaair.org/ has been mentioned, I also find techpreservation useful. Note that techpreservation uses DjVu format. I use the DjVu-6.1.4-en-r2013 plugin with Firefox under Windows XP and 7.

Edit: fixed tube key reference. Learned something new