Mercury Model 501 Component Substitutor Manual Sorry, this product cannot be purchased. $8.50 Category: Mercury Description Description For sale is reprint of Mercury 501 Component Substitutor Manual. Manual is 11 pages long, include part list and Circuit Diagram . Related products Mercury 1100 1100A 1100B Tube Chart 1978 $9.99 Read more Mercury 1000 Tube Tester Tube Chart Updated 1971 version $8.49 Read more Mercury 1100A Tube Tester Instruction Manual with Tube Data $8.49 Read more Mercury 880 Cathode Ray Tube Tester Instruction Manual and tube data $8.99 Read more