(1) Tested Tung Sol 5U8 Tube Date Code KA3 Triode Pentode Tube

(1) Tested Sylvania 5X8 Tube Date Code GL ELM Triode Pentode Converter Tube

(1) Tested Tung Sol 5U8 Tube with Box Date Code NC1 Triode Pentode Tube

(1) Tested Motorola 6DX8 Tube Date Code 7M-1584 Japan Triode Pentode Tube

(1) Tested RCA 6CX8 Tube with Box Date Code CR Medium Mu Triode Pentode Tube

(1) Tested Sylvania 6CU8 Tube Date Code NR DEK Triode Pentode Vacuum Tube

(1) Tested Westinghouse 6JW8 Tube Date Code 81-09 Triode and Pentode Tube (b)

(1) Tested Sylvania 6JV8 Tube with Box Date Code NR AAA Triode Pentode Tube