(!!!!) (Best Single) 420A Western Electric NOS 1977 (2.2/2.3ma) 1-2% section balance
$ 69.99
1 tube) 420A Western Electric NOS 1977 1-2% section balance
1 section) 2.2ma Gm=1600
1 section) 2.3ma Gm=1600
Tested on Amplitrex
Vplate=180V
Vgrid=-.1V
Good mA = 1.4-1.8ma
Good Gm = 1300-1500
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