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

(1) Tested ITT 6X8 Tube with Box Date Code 1109 Japan Triode Pentode Converter

(1) Tested GE 6X8 Tube with Box Date Code 61-22 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 Sylvania 6JC8 Tube with Box Date Code NR EDF Triode Pentode Tube

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

(1) Tested Rad-Tel 6X8 Tube Date Code 5-66 6X8 Triode Pentode Converter Tube