Matched Pair RCA Black Plate 6CG7 6FQ7 Vacuum Tubes Valves With Shields Valvo NOS-Testing This Sylvania triple mica 12AU7A

This Sylvania triple mica 12AU7A / ECC82 dual triode was tested on our Paul Hart-calibrated TV7/U for shorts

Minimum is 25

Sylvania-BRANDED 13GB5 / XL500 tube tested to spec on our Paul Hart-calibrated TV7/U

The remaining two are labeled "1X2B

not included) and they sound excellent

Matched Pair RCA Black Plate 6CG7 6FQ7 Vacuum Tubes Valves With Shields Valvo NOS-Testing This Sylvania triple mica 12AU7AThis matched pair of RCA black plate 6CG7 6FQ7 dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 68 68 while Tube Two measured 74 74 where minimum (65%) is 50 50 and 100% is 77 77 These tubes have steel support rods and copper support rods for their harp shaped getters. There is a shield between the triodes for reduced cross talk. I have played them in my AC