Hi, Bob, and welcome to FixYa.
If the manual is in digital format on your computer, there are several remedies for this.
On a Microsoft Windows computer, there is a "magnifier" tool available that will increase the size of whatever you are viewing on the screen. To utilize this tool. you'll need to go to the "Start" button, click it and then select "Accessories".
There are also free, downloadable magnifiers available. A good one that I have used in the past can be found here:
Finally, if it is a manual that is in a document format known as ".pdf" (Example: Manual.pdf), the program that is used to open this type of document has it's own built in magnifier, indicated by a "plus" or a "minus" sign in the tool bar or under the "View" menu. There you are able to resize the document.
Hope this helps-