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

(1) Tested Motorola 6X8 Tube with Box Code 2-26 Triode Pentode Converter Tube

(1) Tested Motorola 6X8 Tube with Box Code 62-26 Triode Pentode Converter Tube

(1) Tested Tung Sol 6X8 Tube with Box Code KR3 Triode Pentode Converter Tube

(1) Tested RCA 6X8 Tube with Box Date Code 4-52 Triode Pentode Converter Tube

(1) Tested Westinghouse 6GH8A Tube with Box Date Code 70-22 Triode Pentode

(1) Tested GE 5X8 Tube with Box Date Code FV General Electric Triode Pentode

(1) Tested Zenith 6KT8 Tube and Box Red Letters Code 74-22 GE EIA Triode Pentode