The manual for the OP-80 paper tape reader is available for download on the internet at no cost, and has been for some time (years), from multiple sources. It's on Howard's site, however, which may be the quickest and easiest way to get it. These are surprisingly valuable, on a few occasions they have gone for over $100 on E-Bay, although $40-$70 is probably more common (that's for the reader itself, of course, not simply the manual).