1 pair) VT-25-A Sylvania 1940”s in white boxes

1 tube) 34mA Gm=2500 like new – dark brown base partially faded printing

1 tube) 38.2ma Gm=3100 NOS light brown base

– not the same as VT-25=10Y

Tested on Amplitrex

Good current range 20-30ma

Vplate=300V Vgrid=-15V

General Information

(Filament=7V @ 1.2A, Vplate=220V, Vgrid=-7V, Iplate=25ma, Mu=6, Rp=6Kohms)

(The VT-25 is built exactly the same as a VT-52, but the plate and grid are spaced differently yielding different Mu factors and plate resistance)