(!!!!) (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 -4.5V
Amplification Factor (mu) = 8
Plate Resistance (approx) 11Kohms
Transconductance = 725mhos
Plate Current = 2.5 mA