374A Western Electric gray plate used/good 1960”s (17.2ma)

374A Western Electric gray plate used/good 1966

1) 17.2ma Gm=3100

Tested on Amplitrex

Vplate=135V

Vscreen=135V

Vgrid=-18V

Good used Ma range = 17-21ma

Good used Gm range = 2800-3000

(374A specs: Vfil=3V @ 530ma, Vplate=135V, Iplate=18ma, Mu=210, Gm=3000, Rp=70K ohms, Pout=1.3 watts)