(!!!) (Pair) CX-301A Cunningham Balloon used/good 1930-1935 (2.2ma and 2.5ma)

1 pair) CX-301-A Cunningham Balloon used/good 1930-1935

1 tube) 2.2ma Gm=600 nickel pins

1 tube) 2.5ma Gm=700 brass pins

Good Ma range 2-3ma

NOS Gm = 700-800

(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