2A3B


2A3

2A3 is a direct-heated cathode power double triode, it is used in classA1, AB1 amplifier.




Heater
Uf ………………………… 2.5 V
If…………………………2.5 A

Maximum Rating
Ua…………………………300 V
Pa…………………………15 W
Rg
with cathode bias…………………………0.5 MΩ
with fixed bias…………………………0.05 MΩ

Direct Interelectrode Capacitances
input………………………… 7.5 PF
output…………………………16.5 PF
grid to plate…………………………5.5 PF

Static parameter
Ua………………………… 300 V
-Ug………………………… 45 V
Ia………………………… 60 mA
Gm………………………… 5.25 mA/V
ri………………………… 0.8 kΩ
μ………………………… 4.2
Pout…………………………3.5 W


Recommended Operating Conditions(reference value)

class A1.single tube.fixed bias.
Ua………………… 250 V
-Ug……………………45 V
RL……………………2.5 kΩ
Ia(0)…………………60 mA
Gm……………………5.25 Ma/V
ri……………………0.8 Kω
μ……………………4.2
Pout……………………3.5 W
Dtot……………………5 %

Push-full.class AB1.
fixed bias                    cathode bias

Ua……………300   300 V
-Ug……………62  Rk=780Ω V
RL……………3     5 kΩ
üg(pk)………87   110 V
Ia(0)…………80   80 mA
Ia(max.sig)…140  100 mA
Pout……………15   10 W
Dtot……………2.5  5 %