(1) Tested Philco Type 24A Tube Engraved Base Date Code U6 24 A Tube Tetrode

(1) Tested RCA Cunningham Type 41 Tube Engraved Base Date Code J12 Power Pentode

(1) Tested Coronado Type 27 Tube with Engraved Base Date Code Y 27 Tube Triode

(1) Tested Philco Type 41 Tube Date Code 7U Engraved Base Power Pentode Tube

(1) Tested Sylvania Type 27 Tube with Engraved Base Date Code E6R 27 Tube Triode

(1) Tested Philco Type 41 Tube Date Code 6S Engraved Base Power Pentode 41 Tube

(1) Tested Tung-Sol Type 24 Tube Engraved Base Date Code 7-3 Tetrode Tube

(1) Tested RCA Cunningham Type 55 Tube Date Code F2 Engraved Base RCA 55 Tube