(!!!) (Best Pair) 6BQ7A GE black plates "U" getter NOS 1957 (12.8/12.2ma and 11.0/11.6ma) (Highest mA and Gm)

1 low noise pair) 6BQ7A GE black plates "U" NOS 1957

1 tube) 12.8/12.2ma Gm=8000/7000

1 tube) 11.0/11.6ma Gm=7700/7800
 

Tested on Amplitrex

Good Ma range 6-8ma

Good Gm = 6000

 
(also see 6BZ7 and 6BK7B)

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