Question : Problem: in depth difrence of 74hc, hct   act  ls   .......

 I wonder for some wery good source with tables on everything  for the difrence of difrent ttl series interconecting etc

NOT just a beginer thing when i said in depth i meen in DEPTH!!

Answer : Problem: in depth difrence of 74hc, hct   act  ls   .......

  i agree that www.fairchidesemi.com   is one of the best sources for ttl logics

 i think you cen found a lot in depth information here
   http://www.nalanda.nitc.ac.in/industry/appnotes/Natsemi/AN-932.pdf#search='ttl%20ls%20als%20hc%20hct'


   on the net have a lot of resources for that do some research around    some of them


   like
   try   i dont know the exact  page where information is but i often use:
  www.nedis.com
      http://home.att.net/
    http://www.nsc.res.in
   www.commet.com.bg