RCA Black Plate 6CG7 6FQ7 Vacuum Tube With Shields NOS-Testing Number Type 30 It has rectangular mica spacers

It has rectangular mica spacers

They have been tested on our Paul Hart-calibrated TV7/U where minimum (65%) is 40 and have the following values in descending order:

This Raytheon 2B7 tube tested to spec on our Paul Hart-calibrated TV7/U

(Minimum (65%) is 33

These two new old stock

RCA Black Plate 6CG7 6FQ7 Vacuum Tube With Shields NOS-Testing Number Type 30 It has rectangular mica spacersThis new old stock testing RCA black plate 6CG7 6FQ7 dual triode was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. It measured a perfectly balanced 80 80 where minimum (65%) is 50 50. This tube has steel support rods; a harp getter and matte black plates. There is a shield between the triodes for reduced cross talk. I have played it in my Schiit Vali 2 headphone amplifier and it sounds