12AT7 RCA Black Plates “”D”” getter used/good mid-1950”s Title: 12AT7

1 low noise tube) 12AT7 RCA Black Plates “”D”” getter used/good mid-1950”s

Amplitrex Test Data:

1 section) 9.6ma Gm=3700

1 section) 9.2ma Gm=4700

Good Ma range for used 7-9ma

Good Gm range for used 4000-5000

- Earmax Anniversary
- Lector
- Berning