Lansdale 12AU7 / ECC82 Vacuum Tube 17MM Black Plates Copper Support Rods Early Production 12DB5 Nonal T13 Transconductance measured 67/73 for Tube

Transconductance measured 67/73 for Tube One and 68/72 for Tube Two

52 and 60 where minimum (65%) is 36 and 100% is 55

They measured 45

new in box 6AH6 tubes tested to spec on our Paul Hart-calibrated TV7/U

This lot of two (one 12K7G and one 12K7GT) National Union 12K7 tubes tested to spec on our Paul Hart-calibrated TV7/U

Lansdale 12AU7 / ECC82 Vacuum Tube 17MM Black Plates Copper Support Rods Early Production 12DB5 Nonal T13 Transconductance measured 67/73 for TubeThis Lansdale (Philco's in house tube manufacturing arm) 12AU7 ECC82 dual triode was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. It measured 70 64 where minimum (65%) is 56 56 and 100% is 86 86. It has shiny 17MM black plates; copper support rods; excellent flashing; a top slanted D getter and L1E date codes. This is an early production 12AU7 not a 12AU7A like most 12AU7s we see these