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Voltage - Dual Triode (similar) ·Triode-Triode

9AU7

Medium-mu twin triode usable as phase inverter, push-pull amplifier, multivibrator, oscillator, and television deflection oscillator/amplifier in series-heater receivers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9A
Socket code
B9A
Base pins
9
Nominal heater
9.4 V / 225 mA

Description

Medium-mu twin triode used as phase inverter, push-pull amplifier, multivibrator, oscillator, and television deflection oscillator/amplifier.

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
9A
Socket code
B9A
Base pins
9
Nominal heater voltage
9.4 V
Nominal heater current
225 mA
Parallel heater voltage
4.7 V
Parallel heater current
450 mA
Series capable
Yes

9A - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN12PBP — Plate (Anode)

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN22G1BG1 — Control Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN32KBK — Cathode

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN4H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN5H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN61PAP — Plate (Anode)

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN71G1AG1 — Control Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN81KAK — Cathode

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

PIN9HCT—HCT — Heater Center Tap

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 130, 9A

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0022 S
Amplification factor
17
Max plate voltage
330 V
Max plate dissipation
2.75 W
Max cathode current
22 mA

Representative row for two identical triode units; 5.5 W is the combined two-plate/two-unit dissipation.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0022 S
Amplification factor
17
Max plate voltage
330 V
Max plate dissipation
2.75 W
Max cathode current
22 mA

Inherited from explicit parent 12AU7A; supplied 9AU7 sheet changes heater characteristics only.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage - series

    9.4 V

    Series

  • Heater current - series

    225 mA

    Series

  • Heater voltage - parallel

    4.7 V

    Parallel

  • Heater current - parallel

    450 mA

    Parallel

  • Heater warm-up time average

    11 s

    Parallel

  • Peak positive pulse plate voltage

    1200 V

    VerticalDeflectionOscillator

  • Peak cathode current

    66 mA

    VerticalDeflectionOscillator

Capacitance

  • Grid-to-plate capacitance

    1.5 pF

    EachUnit

Data set 02

1966 Tung Sol Electronic Tubes 2 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Voltage

    100 V

    ClassA1

  • Grid Voltage

    0 V

    ClassA1

  • Plate Current

    11.8 mA

    ClassA1

  • Plate Voltage

    250 V

    ClassA1

  • Grid Voltage

    -8.5 V

    ClassA1

  • Plate Current

    10.5 mA

    ClassA1

  • Peak Positive Pulse Plate Voltage

    1200 V

    VerticalDeflection

Data set 03

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater voltage series

    12.6 V

    SeriesHeater

  • Heater current series

    150 mA

    SeriesHeater

  • Heater voltage parallel

    6.3 V

    ParallelHeater

  • Heater current parallel

    300 mA

    ParallelHeater

  • Plate voltage

    100 V

    ClassA1;PublishedPoint1

  • Plate voltage

    250 V

    ClassA1;PublishedPoint2

  • Grid voltage

    0 V

    ClassA1;PublishedPoint1

  • Grid voltage

    -8.5 V

    ClassA1;PublishedPoint2

  • Amplification factor

    19.5

    ClassA1;PublishedPoint1

  • Amplification factor

    17

    ClassA1;PublishedPoint2

  • Plate resistance

    6250 ohm

    ClassA1;PublishedPoint1

  • Plate resistance

    7700 ohm

    ClassA1;PublishedPoint2

  • Transconductance

    3100 µS

    ClassA1;PublishedPoint1

  • Transconductance

    2200 µS

    ClassA1;PublishedPoint2

  • Plate current

    11.8 mA

    ClassA1;PublishedPoint1

  • Plate current

    10.5 mA

    ClassA1;PublishedPoint2

Other

  • Maximum plate voltage

    330 V

    ClassA1

  • Maximum cathode current

    22 mA

    ClassA1

  • Maximum plate dissipation

    2.75 W

    ClassA1

  • Peak heater-cathode voltage

    200 V

  • Peak negative-pulse grid voltage

    660 V

    HorizontalDeflectionOscillator

  • Peak cathode current

    330 mA

    HorizontalDeflectionOscillator

  • Peak negative-pulse grid voltage

    440 V

    VerticalDeflectionOscillator

  • Peak cathode current

    66 mA

    VerticalDeflectionOscillator

  • Peak positive-pulse plate voltage

    1200 V

    VerticalDeflectionAmplifier

  • Heater voltage nominal

    9.4 V

  • Heater current nominal

    225 mA

  • Heater voltage series

    9.4 V

    Series

  • Heater current series

    225 mA

    Series

  • Heater voltage parallel

    4.7 V

    Parallel

  • Heater current parallel

    450 mA

    Parallel

Capacitance

  • Grid-to-plate capacitance

    1.5 pF

  • Grid-to-cathode-and-heater capacitance

    1.6 pF

  • Plate-to-cathode-and-heater capacitance

    0.5 pF

SECTION 2

Triode

Characteristics

  • Heater voltage series

    12.6 V

    SeriesHeater

  • Heater current series

    150 mA

    SeriesHeater

  • Heater voltage parallel

    6.3 V

    ParallelHeater

  • Heater current parallel

    300 mA

    ParallelHeater

  • Plate voltage

    100 V

    ClassA1;PublishedPoint1

  • Plate voltage

    250 V

    ClassA1;PublishedPoint2

  • Grid voltage

    0 V

    ClassA1;PublishedPoint1

  • Grid voltage

    -8.5 V

    ClassA1;PublishedPoint2

  • Amplification factor

    19.5

    ClassA1;PublishedPoint1

  • Amplification factor

    17

    ClassA1;PublishedPoint2

  • Plate resistance

    6250 ohm

    ClassA1;PublishedPoint1

  • Plate resistance

    7700 ohm

    ClassA1;PublishedPoint2

  • Transconductance

    3100 µS

    ClassA1;PublishedPoint1

  • Transconductance

    2200 µS

    ClassA1;PublishedPoint2

  • Plate current

    11.8 mA

    ClassA1;PublishedPoint1

  • Plate current

    10.5 mA

    ClassA1;PublishedPoint2

Other

  • Maximum plate voltage

    330 V

    ClassA1

  • Maximum cathode current

    22 mA

    ClassA1

  • Maximum plate dissipation

    2.75 W

    ClassA1

  • Peak heater-cathode voltage

    200 V

  • Peak negative-pulse grid voltage

    660 V

    HorizontalDeflectionOscillator

  • Peak cathode current

    330 mA

    HorizontalDeflectionOscillator

  • Peak negative-pulse grid voltage

    440 V

    VerticalDeflectionOscillator

  • Peak cathode current

    66 mA

    VerticalDeflectionOscillator

  • Peak positive-pulse plate voltage

    1200 V

    VerticalDeflectionAmplifier

  • Heater voltage nominal

    9.4 V

  • Heater current nominal

    225 mA

  • Heater voltage series

    9.4 V

    Series

  • Heater current series

    225 mA

    Series

  • Heater voltage parallel

    4.7 V

    Parallel

  • Heater current parallel

    450 mA

    Parallel

Capacitance

  • Grid-to-plate capacitance

    1.5 pF

  • Grid-to-cathode-and-heater capacitance

    1.6 pF

  • Plate-to-cathode-and-heater capacitance

    0.35 pF

Data set 04

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate Supply Voltage 100

    250 V

    Published in approved ECC82 target datasheet entry; Section1

  • Cathode-Bias Resistor 270

    200 Ω

    Published in approved ECC82 target datasheet entry; Section1

  • Plate Resistance (Approx.) 15000

    10900 Ω

    Published in approved ECC82 target datasheet entry; Section1

  • Transconductance 4000

    5500 µS

    Published in approved ECC82 target datasheet entry; Section1

  • Grid Voltage (Approx.) for plate current of 10 /iA —5

    12 V

    Published in approved ECC82 target datasheet entry; Section1

  • Plate Current 3.7

    10 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Series 7 9.4

    12.6 V

    Published in approved ECC82 target datasheet entry; Section1

  • Parallel 3.5 4.7

    6.3 V

    Published in approved ECC82 target datasheet entry; Section1

  • Series 0.3 0.225

    150 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Parallel 0.6 0.45

    300 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Heater Warm-up Time (Parallel, Average) 11

    11 seconds

    Published in approved ECC82 target datasheet entry; Section1

  • Plate Voltage

    330 V

    Published in approved ECC82 target datasheet entry; Section1

  • Cathode Current

    22 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Each Plate

    2.75 W

    Published in approved ECC82 target datasheet entry; Section1

  • Both Plates (Both units operating)

    5.5 W

    Published in approved ECC82 target datasheet entry; Section1

  • Plate Resistance (Approx.) 6250

    7700 Ω

    Published in approved ECC82 target datasheet entry; Section1

  • Transconductance 3100

    2200 µS

    Published in approved ECC82 target datasheet entry; Section1

  • For fixed-bias operation

    0.25 MΩ

    Published in approved ECC82 target datasheet entry; Section1

  • For cathode-bias operation

    1 MΩ

    Published in approved ECC82 target datasheet entry; Section1

  • DC Plate Voltage 330

    330 V

    Published in approved ECC82 target datasheet entry; Section1

  • Peak Negative-Pulse Grid Voltage 440

    660 V

    Published in approved ECC82 target datasheet entry; Section1

  • Peak Cathode Current 66

    330 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Average Cathode Current 22

    22 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Each Plate 2.75

    2.75 W

    Published in approved ECC82 target datasheet entry; Section1

  • Both Plates (Both units operating) 5.5

    5.5 W

    Published in approved ECC82 target datasheet entry; Section1

  • Grid-Circuit Resistance 2.2

    2.2 MΩ

    Published in approved ECC82 target datasheet entry; Section1

  • DC Plate Voltage

    330 V

    Published in approved ECC82 target datasheet entry; Section1

  • Peak Positive-Pulse Plate Voltage#

    1200 V

    Published in approved ECC82 target datasheet entry; Section1

  • Peak Negative-Pulse Grid Voltage

    275 V

    Published in approved ECC82 target datasheet entry; Section1

  • Peak Cathode Current

    66 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Average Cathode Current

    22 mA

    Published in approved ECC82 target datasheet entry; Section1

  • Each Plate

    275 V

    Published in approved ECC82 target datasheet entry; Section1

  • Grid-Circuit Resistance, for cathode-bias operation

    2.2 MΩ

    Published in approved ECC82 target datasheet entry; Section1

  • # Pulse duration must not exceed 15% of a vertical scanning cycle (

    2.5 milliseconds

    Published in approved ECC82 target datasheet entry; Section1

Capacitance

  • Grid to Plate 1.5

    1.5 pF

    Published in approved ECC82 target datasheet entry; Section1

  • Grid to Cathode and Heater 1.6

    1.6 pF

    Published in approved ECC82 target datasheet entry; Section1

  • Plate to Cathode and Heater 0.5

    0.35 pF

    Published in approved ECC82 target datasheet entry; Section1

Characteristic

  • Plate Current 11.8

    10.5 mA

    Published in approved ECC82 target datasheet entry; Section1