I run across repair books over on archive.org every once in a while, I'll try to post them here. Some require a sign up but it's painless and there's a ton more books to look over. Compact Disc Player Maintenance and Repair, 1987 https://archive.org/details/compactdiscplaye0000mcco/mode/2up?q=&view=theater
Understanding And Servicing CD Players (1994) https://archive.org/details/understandingandservicingcdplayers
thanks for the tip on "CD Player Maintenance". "Understanding CD Players" I have as a paperback and on Kindle, even read it... twice!!... A lot of Discmans have their voltage regulators and DC-DC converters busted, understanding those is on my 'to do' list One book I keep recommending for the beginners like myself is How to Diagnose and Fix Everything Electronic