(!) 448A Western Electric smooth top used/good 1965-1966 (1 pair: 19.2ma and 20.8ma) (Matched on Amplitrex)

1 pair) 448A Western Electric smooth top used/good 1965-1966 – reboxed

1 tube) 19.2ma Gm=25,000

1 tube) 20.8ma Gm=23,000

Amplitrex Test Data:

Vplate=135V

Vscreen=135V

Vgrid=-2

Good Ma range 20-30ma

Good Gm = 23,000 – 27,000

DIY pentode