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Voltage - Dual Triode (similar) ·Triode-Triode

5751

Special-quality high-mu twin triode for low-noise voltage amplification and demanding communication or industrial service, offering lower gain than the 12AX7 family with controlled performance.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B9A
Base pins
9
Nominal heater
12.6 V / 175 mA

Description

High-reliability high-mu dual triode for voltage amplification and general-purpose low-level amplifier service.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B9A
Base pins
9
Nominal heater voltage
12.6 V
Nominal heater current
175 mA
Parallel heater voltage
6.3 V
Parallel heater current
350 mA
Series capable
Yes

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
58000 Ω
Transconductance
0.0012 S
Amplification factor
70
Max plate voltage
330 V
Max plate dissipation
1.1 W
Max cathode current
6 mA
Rectifier max heater-cathode voltage
100 V

Representative row for two identical high-mu triode sections; absolute maxima used.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
58000 Ω
Transconductance
0.0012 S
Amplification factor
70
Max plate voltage
330 V
Max plate dissipation
1.1 W
Max cathode current
6 mA

Second identical physical triode section; added to align rows with SectionCount.

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

1960 RCA Industrial and Communications Types

Published operating points and test conditions from this source.

SECTION 1

Triode

CrossReference

  • Prototype / equivalent family

    12AX7

Data set 02

1963 Siemens

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    6.3 V

  • Heater current

    350 mA

Characteristics

  • Transconductance

    1200 µS

    Nominal/Bogey

  • Amplification factor

    70

    Nominal/Bogey

Data set 03

1966 Tung Sol Electronic Tubes 3 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Grid-to-plate capacitance each section

    1.4 pF

    WholeTube

  • Input capacitance

    1.4 pF

    WholeTube

  • Output capacitance section 1

    0.7 pF

    WholeTube

  • Output capacitance section 2

    0.36 pF

    WholeTube

Other

  • Maximum plate voltage

    330 V

    WholeTube

  • Maximum plate dissipation each section

    0.8 W

    WholeTube

  • Plate voltage

    100 V

    100VPoint

  • Grid bias voltage

    -1 V

    100VPoint

  • Amplification factor

    70

    100VPoint

  • Plate resistance

    58000 ohm

    100VPoint

  • Transconductance

    1200 µS

    100VPoint

  • Plate current

    0.8 mA

    100VPoint

  • Plate voltage

    250 V

    250VPoint

  • Grid bias voltage

    -3 V

    250VPoint

  • Amplification factor

    70

    250VPoint

  • Plate resistance

    58000 ohm

    250VPoint

  • Transconductance

    1200 µS

    250VPoint

  • Plate current

    1 mA

    250VPoint

Data set 04

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Voltage

    250 V

    ClassA EachSection

  • Grid Bias Voltage

    -3 V

    ClassA EachSection

Characteristic

  • Plate Current

    1 mA

    ClassA EachSection

Data set 05

1968 Mazda Belvu

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    350 mA

    Nominal

  • Maximum Plate Voltage

    330 V

  • Maximum Plate Dissipation

    0.8 W

  • Maximum Cathode Current

    6 mA

Characteristic

  • Transconductance

    1200 µS

    Typical

  • Amplification Factor

    70

    Typical

  • Plate Resistance

    58000 ohm

    Typical

Data set 06

1971 RCA HB3 Binder 3 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Voltage (AC or DC) — published value 1

    12.6 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Voltage (AC or DC) — published value 2

    10 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Voltage (AC or DC) — published value 3

    6.3 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Voltage (AC or DC) — published value 4

    10 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Current — published value 1

    0 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Current — published value 2

    175 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Current — published value 3

    350 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Voltage — published value 1

    100 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Voltage — published value 2

    250 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Grid Voltage — published value 1

    -1 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Grid Voltage — published value 2

    -3 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Resistance — published value 1

    58000 ohm

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Resistance — published value 2

    58000 ohm

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 1

    1200

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 2

    1200

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 1

    0.9 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 2

    1 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 1 -Plate of — published value 1

    1

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 1 -Plate of — published value 2

    6

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 2-Grid of — published value 1

    2

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 2-Grid of — published value 2

    7

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 4 -Heater — published value 1

    4

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 4 -Heater — published value 2

    9

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Pin 5-Heater

    5

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Heater Current — published value 1

    1 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Heater Current — published value 2

    160 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Heater Current — published value 3

    190 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 1

    1 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 2

    2 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 3

    0.4 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 4

    1.6 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 1

    1 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 2

    3 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Plate Current — published value 3

    10.5 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 1

    1

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 2

    2

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 3

    900

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Transconductance — published value 4

    1600

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Reverse Grid Current — published value 1

    1 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Reverse Grid Current — published value 2

    4 A

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Reverse Grid Current — published value 3

    400 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Mote 2: Witty do plate voltage of 250 volts and do grid voltage of -3 — published value 1

    2 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Mote 2: Witty do plate voltage of 250 volts and do grid voltage of -3 — published value 2

    250 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Mote 2: Witty do plate voltage of 250 volts and do grid voltage of -3 — published value 3

    -3 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Note 3: With do plate voltage of 250 volts, plate load resistance of 0.1 — published value 1

    3 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Note 3: With do plate voltage of 250 volts, plate load resistance of 0.1 — published value 2

    250 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Note 3: With do plate voltage of 250 volts, plate load resistance of 0.1 — published value 3

    0.1 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • meg on m, and do grid voltage of —10.5 volts.. Each unit is tested

    10.5 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Note u: With do plate voltage of 250 volts, grid resistor of 1.0 meg ohm, — published value 1

    250 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Note u: With do plate voltage of 250 volts, grid resistor of 1.0 meg ohm, — published value 2

    1 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

Other

  • PLATE VOLTAGE

    330 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Negative bias value

    55 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Positive bias value

    0 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • PLATE DISSIPATION

    0.8 mA

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Heater negative with respect to cathode

    100 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

  • Heater positive with respect to cathode

    100 V

    Published datasheet value; multiple values on a source row represent separate source-table conditions or limits.

Data set 07

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Plate voltage

    100 V

    ClassA

  • Grid voltage

    -1 V

    ClassA

  • Plate current

    0.9 mA

    ClassA

  • Plate voltage

    250 V

    ClassA

  • Grid voltage

    -3 V

    ClassA

  • Plate current

    1 mA

    ClassA

Data set 08

2026 JJ Electronic

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Transconductance

    1200 µS

  • Grid To Cathode Capacitance

    1.6 pF

  • Plate Capacitance

    0.33 pF

  • Grid To Plate Capacitance

    1.7 pF