I have here an old 1955 IBM "Manual of Instruction: Electronics" Publication 'Form 22-6253-0 (12-55: 11M-W)' which has some vacuum-tube based logic circuits in it (mostly simple stuff as the book seems to be at a high-school or undergraduate level and is mostly an overview). However, it doesn't list the resistor values (except for the card punch sorter circuit), and hence has the same issues as the schematics available elsewhere, it would seem. Should I scan it? Its about 100 pages, so it will take a while. -- Jonathan Gevaryahu jgevaryahu(@t)hotmail(d0t)com jzg22(@t)drexel(d0t)edu