37 Raytheon NOS 1946 (7.3ma) (Highest mA)

37 Raytheon NOS 1946

7.3ma

Gm=1200

Test parameters:

Vplate=250V

Vgrid=-18V

Iplate good range 6.5-8ma

Gm=1000-1100

(Filament=6.3V @ 300ma, many think the 37 sounds better than the 76)