Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Tung-Sol 6K6 These four metal base National

These four metal base National Union 6Q7GT tubes tested to spec on our Paul Hart-calibrated TV7/U

Transconductance readings are 25

They measured 82/76 for Tube One and 85/74 for Tube Two

" "My Darling's Ring

Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Tung-Sol 6K6 These four metal base NationalThis new old stock, new in box matched pair of RCA 12SN7GTA 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 76 76 and Tube Two measured 79 77 where minimum (65%) is 50 50. They have short bases; tall bottles; D getters; steel support rods; DB and CV batch codes, respectively, and their top mica spacers have two X patterns incised into them. I am playing them