If anyone is interested , this page explains things like PID's, symbol rates, 4:2:2, DCII, DBS, DSS, etc. I know that a lot of you are well versed in these things, but maybe others (like me) might benefit from looking through this:
http://www.coolstf.com/mpeg/index.html
Some stuff might be a little dated. (2003)
http://www.coolstf.com/mpeg/index.html
Some stuff might be a little dated. (2003)