For sale are reprints of Jackson 648 Tube Test Data.
User Manual is 12 pages long, was scanned from tube test chart removed from tester. Chart is version 648-33 dated 3-69
Real Paper Manual. Quality Printed and Comb Bound. Scanned from original at 800dpi, restored in Photoshop, Laser printed on premium acid free paper, they will serve for years. Cover page printed on Cover Stock.