For sale is reprint of Hickok 539A Tube Tester manual. Manual 12 pages long and includes 11″x17″ foldout of Circuit Diagram.
Manual comes with 4 pages of Ballast Tube Data, Part list and Operating Instructions. Manual is dated 1949. Manual also includes 2 Bulletins (T-123, T-127) 6 pages of additional data for new Tube Types.