(!!!!) (Best Pair) CX-301-A Cunningham used/good 1928-1930 era (2.6ma and 2.5ma) (same Gm)

1 pair) CX-301-A Cunningham used/strong 1930 era 1 tube) 2.6ma Gm=700 (1928) 1 tube) 2.5ma Gm=700 (1930 era) slightly taller glass   Good Ma range 2-3ma NOS Gm = 800+   (Filament=5V @ 250ma, Vplate max=135V) - Crosley C5 1926   Class A Amplifier: -----------------Plate Voltage = 90 VGrid No. 1 Voltage -4.5VAmplification Factor (mu) = 8Plate Resistance (approx) 11KohmsTransconductance = 725mhosPlate Current = 2.5 mA