How can you authenticate the autograph baseballs you got during the 1980s?

An autograph that is not authenticated by a creditable company could sell at half the market value or less. Two of the top, and most trusted authenticators are PSA/DNA, and James Spence Authentic (JSA). Collectors will pay more for signatures authenticated by either one. It may sound odd but in some cases PSA/DNA, and JSA authenticated signatures may sell higher than a Letter of authenticity from an unknown or less trusted authenticator that witnessed the signing even though PSA/DNA, and JSA did not. It's just a matter of collectors trust, and collectors will pay more for it. Check the respective websites Show Schedule to see if they will be in the area that you live. They also do business through the mail. I will leave a link below for both websites.