Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Number 2 Red Seal

Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Number 2 Red SealThis 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

This lot of twelve new old stock

new in box RCA 3A3C tested to spec on our Paul Hart-calibrated TV7/U

This Super Silvertone 6J7G tube was tested on our Paul Hart-calibrated TV7/U for shorts

All measured 1950 micromhos where new/nominal is 2000 and minimum (65%) is 1300

Transconductance: 1541 / 1532

They measured 52/52

72 and 75 respectively

side-D getter

This new old stock-testing matched pair of GE 12SN7GT dual triodes was tested on our Paul Hart-calibrated TV7/U for shorts

1480 micromhos' transconductance

new in box matched pair of GE 12SL7 / 12SL7GT dual triodes was tested on our Pau Hart-calibrated TV7/U for shorts

Dynamic Range: -77