This listing is for a lot of 10 RCA Black Plate 12AU7 Vacuum Tubes

- All with Black Plates
- All with Slant Square Getters

Test Results: 
NO Shorts, No Leakage, No Gas, No Micro-Phonics detected

Tube 1:  Side 1:   94 = 2,350 uMhos Transconductance(Gm)  at 7.6 mA (Ia =Anode Plate Current)
              Side 2: 100 = 2,500 uMhos Transconductance(Gm)  at 8.2 mA (Ia =Anode Plate Current)

Tube 2:  Side 1:   94 = 2,350 uMhos Transconductance(Gm)  at 7.8 mA (Ia =Anode Plate Current)
              Side 2: 101 = 2,525 uMhos Transconductance(Gm)  at 10.1 mA (Ia =Anode Plate Current)

Tube 3:  Side 1:   79 = 1,975 uMhos Transconductance(Gm)  at 6.5 mA (Ia =Anode Plate Current)
              Side 2:   84 = 2,100 uMhos Transconductance(Gm)  at 7 mA (Ia =Anode Plate Current)

Tube 4:  Side 1: 108 = 2,700 uMhos Transconductance(Gm)  at 10.2 mA (Ia =Anode Plate Current)
              Side 2: 104 = 2,600 uMhos Transconductance(Gm)  at 9.3 mA (Ia =Anode Plate Current)


Tube 5:  Side 1:   92 = 2,300 uMhos Transconductance(Gm)  at 7.8 mA (Ia =Anode Plate Current)
              Side 2:   97 = 2,425 uMhos Transconductance(Gm)  at 8.5 mA (Ia =Anode Plate Current)

Tube 6:  Side 1:   98 = 2,450 uMhos Transconductance(Gm)  at 7.9 mA (Ia =Anode Plate Current)
              Side 2:   88 = 2,200 uMhos Transconductance(Gm)  at 6.7 mA (Ia =Anode Plate Current)

Tube 7:  Side 1: 107 = 2,675 uMhos Transconductance(Gm)  at 9.4 mA (Ia =Anode Plate Current)
              Side 2:   99 = 2,475 uMhos Transconductance(Gm)  at 8.3 mA (Ia =Anode Plate Current)

Tube 8:  Side 1:   93 = 2,325 uMhos Transconductance(Gm)  at 8.7 mA (Ia =Anode Plate Current)
              Side 2:   89 = 2,225 uMhos Transconductance(Gm)  at 8.1 mA (Ia =Anode Plate Current)

Tube 9:  Side 1:   76 = 1,900 uMhos Transconductance(Gm)  at 7.5 mA (Ia =Anode Plate Current)
              Side 2:   83 = 2,075 uMhos Transconductance(Gm)  at 7.3mA (Ia =Anode Plate Current)

Tube 10:  Side 1:   82 = 2,050 uMhos Transconductance(Gm)  at 7.3 mA (Ia =Anode Plate Current)
                Side 2:   75 = 1,875 uMhos Transconductance(Gm)  at 6.8 mA (Ia =Anode Plate Current)


Minimum good on TV7: 56 = 1,400 uMhos.

For Reference: The Minimum good value for a ECC82/12AU7 tube tested on all TV7 versions is 56/56 = 1,400/1,400 uMhos Gm 'Bogey': Factory Data Sheet NOS when new 88/88 = 2,200/2,200 (μ℧ ) uMhos Transconductance (Gm) at 10.5/10.5mA Anode Plate Current Dissipation.

All tested on Dan Nelson restored, upgraded and calibrated, TV7A/U with Digital Meter and mA.

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