(!!!) (Best Pair #3) 448A Western Electric tipped top used/strong 1965 (30ma and 32ma) (Matched on Amplitrex)

1 pair) 448A Western Electric “”tipped top”” used/strong D getter halo 1965 in white boxes

1 tube) 30ma Gm=27,000

1 tube) 32ma Gm=28,700

Amplitrex Test Data:

Vplate=135V

Vscreen=135V

Vgrid=-2.5V

Good Ma range 18-25ma

Good Gm = 25,000

DIY pentode