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Power - Triode ·Triode-Triode

6B5

Direct-coupled twin-triode power amplifier for Class-A audio-frequency output service, using internally related input and output sections to develop bias and deliver power efficiently.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
6AS
Socket code
UX6
Base pins
6
Nominal heater
6.3 V / 800 mA

Description

Indirectly heated direct-coupled power-amplifier triode for Class A audio-frequency service.

Socket description

Small 6-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
6AS
Socket code
UX6
Base pins
6
Nominal heater voltage
6.3 V
Nominal heater current
800 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

6AS - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
24100 Ω
Transconductance
0.0024 S
Amplification factor
58
Max plate voltage
325 V

Published static characteristics are given for the combined dynamic-coupled structure.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0024 S
Amplification factor
58
Max plate voltage
325 V

Electrical section reconstructed from published ratings/characteristics; transconductance promoted in A/V.

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

Other

  • 'r Maximum Plate Voltage

    325 V

    Published table

  • Output-Plate Voliage

    250 V

    ClassA; Column1

  • Output-Plate Voliage

    300 V

    ClassA; Column2

  • Output-Plate Voliage

    325 V

    ClassA; Column3

  • Input-Plate Voltage

    250 V

    ClassA; Column1

  • Input-Plate Voltage

    300 V

    ClassA; Column2

  • Input-Plate Voltage

    325 V

    ClassA; Column3

  • Amplification Factor

    58

    ClassA

  • Transconductance

    2400 uS

    ClassA

  • Output-Plate Current

    33 mA

    ClassA; Column1

  • Output-Plate Current

    45 mA

    ClassA; Column2

  • Output-Plate Current

    51 mA

    ClassA; Column3

  • Input-Plate Current

    6.5 mA

    ClassA; Column1

  • Input-Plate Current

    8 mA

    ClassA; Column2

  • Load Resistance

    7000

    ClassA; Column1

  • Load Resistance

    7000

    ClassA; Column2

  • Load Resistance

    7000

    ClassA; Column3

  • Signal Voltage RMS

    13.5 V

    ClassA; Column1

  • Signal Voltage RMS

    15 V

    ClassA; Column2

  • Output-Plate Voltage

    250 V

    ClassA; Column1

  • Output-Plate Voltage

    300 V

    ClassA; Column2

  • Output-Plate Voltage

    325 V

    ClassA; Column3

  • Output-Plate Current (per tube)

    35 mA

    ClassA; Column1

  • Output-Plate Current (per tube)

    45 mA

    ClassA; Column2

  • Output-Plate Current (per tube)

    51 mA

    ClassA; Column3

  • Input-Plate Current (per tubse)

    645 mA

    ClassA; Column1

  • Input-Plate Current (per tubse)

    8 mA

    ClassA; Column2

  • Input-Plate Current (per tubse)

    9 mA

    ClassA; Column3

  • Load Resistance (rlate to plate)

    10000 ohm

    ClassA; Column1

  • Load Resistance (rlate to plate)

    10000 ohm

    ClassA; Column2

  • Load Resistance (rlate to plate)

    10000 ohm

    ClassA; Column3

  • Power Output

    8.5 W

    ClassA; Column1

  • Power Output

    10 W

    ClassA; Column2

  • Power Output

    13.5 W

    ClassA; Column3

  • Signal Voltage RMS (grid to grid)

    38 V

    ClassA; Column1

  • Signal Voltage RMS (grid to grid)

    38 V

    ClassA; Column2

  • Signal Voltage RMS (grid to grid)

    42 V

    ClassA; Column3

  • OUTPUT SECTION

    6

    ClassA

  • o &———‘ Y ouTPUT——

    0

    ClassA; Column1

  • o &———‘ Y ouTPUT——

    3

    ClassA; Column2

Data set 02

1938 Triadyne

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • PlateCurrentOutput

    45 mA

    ClassA;OneTube;At 300 V

  • PlateCurrentInput

    8 mA

    ClassA;OneTube;At 300 V

  • Load Resistance

    7000 ohm

    ClassA;OneTube;At 300 V

  • Power Output

    4 W

    ClassA;OneTube;At 300 V

  • Power Output

    10 W

    PushPull;ClassA;TwoTubes;At 300 V

Data set 03

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 2

Triode

Characteristic

  • Tension de chauffage (CA. ou CC.) ... . .. .o 6,3 volts

    6.3 V

    Tension de chauffage (CA. ou CC.) ... . .. .o 6,3 volts

  • Courant de chauffage ... ... . i v r 4 0,8 ampére

    800 mA

    Courant de chauffage ... ... . i v r 4 0,8 ampére

  • Tension de chauffage ... ... ... .. .. .. 6,3 volts

    6.3 V

    Tension de chauffage ... ... ... .. .. .. 6,3 volts

  • Tension grille (entrée) ... .. . v o 0 volt

    0 V

    Tension grille (entrée) ... .. . v o 0 volt

  • Courant plaque (sortie) ... . .. oo e 42 ma.

    42 mA

    Courant plaque (sortie) ... . .. oo e 42 ma.

  • Courant plaque (entrée) ... ... .. v .. ... 9 ma,

    9 mA

    Courant plaque (entrée) ... ... .. v .. ... 9 ma,

  • Résistance interne ... ... ... .. .. .. .. 24,000 ohms

    24 ohms

    Résistance interne ... ... ... .. .. .. .. 24,000 ohms

  • Conductance mutuelle* ... ... .. .. .. .. 2,400 ymhos

    2.4 ymhos

    Conductance mutuelle* ... ... .. .. .. .. 2,400 ymhos

  • Puissance de sortie** .. .. .. . .. .. 4 watts

    4 W

    Puissance de sortie** .. .. .. . .. .. 4 watts

  • Puissance de sortie*** ., e e 6,5 watts

    6.5 W

    Puissance de sortie*** ., e e 6,5 watts

  • capacité. La charge optimum pour un seul tube est 7.000 ohms.

    7 ohms

    capacité. La charge optimum pour un seul tube est 7.000 ohms.

  • tation de 300 volts. Cependant, on peut élever la tension jusqu’a

    300 V

    tation de 300 volts. Cependant, on peut élever la tension jusqu’a

Other

  • Tension de plaque (sortie) ... ... .. .. .. 300 volts max.

    300 V

    Tension de plaque (sortie) ... ... .. .. .. 300 volts max.

  • Tension plaque (entrée) ... ... ... ... ... .. 300 volts max.

    300 V

    Tension plaque (entrée) ... ... ... ... ... .. 300 volts max.

Data set 04

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate supply voltage

    300 V

    ClassA

  • Input plate voltage

    300 V

    ClassA

  • Grid voltage

    0 V

    ClassA

  • Plate current

    45 mA

    ClassA

  • Input plate current

    8 mA

    ClassA

  • Load resistance

    7000 ohm

    ClassA

  • Power output

    4 W

    ClassA

Data set 05

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    6.3 V

  • Heater current

    800 mA

  • Plate current

    33 mA

    Typical operating conditions

SECTION 2

Triode

Other

  • Heater voltage

    6.3 V

  • Heater current

    800 mA

  • Plate current

    33 mA

    Typical operating conditions