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Power - Triode ·Triode

6B4G

Directly heated low-mu audio power triode closely related electrically to the 6A3 but using a 6.3 V filament. It provides several watts of single-ended Class A output and is also suitable for push-pull audio stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
5S
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 1 A

Description

Power-amplifier triode; the supplied sheet refers to Type 6A3 for additional characteristics and applications.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
5S
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
1 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

5S - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN1ISAIS — Internal Screen

EIA chart transcription; manufacturer corroboration pending

Unverified

EIA Base Connections, printed page 127, 5S

PIN2F—F — Filament

EIA chart transcription; manufacturer corroboration pending

Unverified

EIA Base Connections, printed page 127, 5S

PIN3PAP — Plate (Anode)

EIA chart transcription; manufacturer corroboration pending

Unverified

EIA Base Connections, printed page 127, 5S

PIN5G1AG1 — Control Grid

EIA chart transcription; manufacturer corroboration pending; preserve source designation G1

Unverified

EIA Base Connections, printed page 127, 5S

PIN7F—F — Filament

EIA chart transcription; manufacturer corroboration pending

Unverified

EIA Base Connections, printed page 127, 5S

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
15 W
Max cathode current
100 mA

Published ratings and characteristics promoted from the approved source.

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

1937 Raytheon Radio Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid-to-plate capacitance

    16 pF

    Section1

  • Input capacitance

    7 pF

    Section1

  • Output capacitance

    5 pF

    Section1

Other

  • Plate voltage

    250 V

    ClassA

  • Control-grid voltage

    -45 V

    ClassA

  • Plate current

    60 mA

    ClassA

  • Load resistance

    2500 Ω

    ClassA

  • Power output

    3.2 W

    ClassA

  • Plate voltage

    325 V

    ClassAB;PushPull;TwoTubes

  • Control-grid voltage

    -68 V

    ClassAB;PushPull;TwoTubes

  • Load resistance plate-to-plate

    3000 Ω

    ClassAB;PushPull;TwoTubes;FixedBias

  • Power output

    15 W

    ClassAB;PushPull;TwoTubes;FixedBias

Characteristic

  • Plate resistance

    800 Ω

    Section1

  • Transconductance

    5250 µS

    Section1

  • Amplification factor

    4.2

    Section1

Data set 02

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Tension filament CA. ou CC. ... ... .. .. .. 6,3 volts

    6.3 V

    Tension filament CA. ou CC. ... ... .. .. .. 6,3 volts

Data set 03

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    250 V

    ClassA;OneTube

  • Grid voltage

    -45 V

    ClassA;OneTube

  • Plate current

    60 mA

    ClassA;OneTube

  • Load resistance

    2500 ohm

    ClassA;OneTube

  • Power output

    3.2 W

    ClassA;OneTube

  • Plate voltage

    325 V

    ClassAB;PushPull;TwoTubes

  • Grid voltage

    -68 V

    ClassAB;PushPull;TwoTubes

  • Plate current

    80 mA

    ClassAB;PushPull;TwoTubes

  • Load resistance

    3000 ohm

    ClassAB;PushPull;TwoTubes

  • Power output

    15 W

    ClassAB;PushPull;TwoTubes

Data set 04

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    6.3 V

  • Heater current

    1 A

  • Plate current

    60 mA

    Typical operating conditions

Data set 05

2026 Sovtek

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Current

    60 mA

    Plate 250 V; ClassA;OneTube

  • Power Output

    3 W

    Plate 250 V; Load 2.5 kohm; ClassA;OneTube