My Hitachi 50UX23K television (ca. 1995) is acting a little funny but it's rather hard to find technical information about products from before the Internet age. There are several companies selling PFD versions of the service manual, but it seemed absurd to pay $10 or more for an unauthorized electronic copy... and I was right! eServiceInfo provides free services manuals and schematics for all sorts of electronics. If you've got something old that you'd like to repair, check there before paying anyone for anything.