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Power - Triode ·Triode

2A340W

Directly heated filamentary Class-A audio power triode with approximately 40 W maximum plate dissipation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX4
Base pins
4
Nominal heater
2.5 V / 2.5 A

Description

A moderate-power, directly heated filamentary triode for Class A service, with a 2.5 V, 2.5 A filament, 40 W plate-dissipation limit, and published interelectrode capacitances.

Socket description

Medium-shell UX 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
UX4
Base pins
4
Nominal heater voltage
2.5 V
Nominal heater current
2.5 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
800 Ω
Transconductance
0.00525 S
Amplification factor
4.2
Max plate voltage
450 V
Max plate dissipation
40 W
Max cathode current
100 mA

JJ Electronic 2A3-40 W moderate-power filamentary Class A triode.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

199X JJ

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Typical Plate Voltage

    250 V

  • TypicalGridVoltage

    -45 V

  • Typical Plate Current

    60 mA

Characteristic

  • Grid Cathode Capacitance

    17 pF

  • PlateCathodeCapacitance

    11 pF

  • GridPlateCapacitance

    7.5 pF