Matched Quad CBS-Hytron 6CL6 Vacuum Tubes Valves Black Plate NOS NIB 6K6 new in box Amperex 9ED4

new in box Amperex 9ED4 tube tested to spec on our Paul Hart-calibrated TV7/U

new in box Sylvania Number 37 tube tested to spec on our Paul Hart-calibrated TV7/U

Transconductance measured 40

Transconductance measured 33 for Tube One and 33 for Tube Two where minimum (65%) is 26

perhaps an 8

Matched Quad CBS-Hytron 6CL6 Vacuum Tubes Valves Black Plate NOS NIB 6K6 new in box Amperex 9ED4This new old stock, new in box matched quad of CBS Hytron black plate 6CL6 tubes were tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 49, 50, 50 and 52 where minimum (65%) is 30. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE