(!!!!!) (Best Overall Pair) 311B Western Electric NOS 1956 and 1964 (35ma and 36ma)
$ 169.99
1 pair) 311B Western Electric NOS "D" getters 1956 and 1964 same build
1 tube) 36ma and Gm=3200 (1956) original box - top cap cleaned of oxidation
1 tube) 35ma and Gm=3050 (1964) in white box
Tested on Amplitrex
Vplate=180V
Vscreen=135V
Vgrid=-15V
Good Ma = 30ma
Good Gm = 2900
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