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Voltage - Dual Triode (similar) ·Triode-Triode

8FQ7

Medium-mu twin triode used as combined horizontal- and vertical-deflection oscillator in television receivers, with published pulse ratings appropriate to sweep-generator service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9LP
Socket code
B9A
Base pins
9
Nominal heater
8.4 V / 450 mA

Description

Medium-mu twin triode used as combined vertical- and horizontal-deflection oscillator in television receivers.

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
9LP
Socket code
B9A
Base pins
9
Nominal heater voltage
8.4 V
Nominal heater current
450 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9LP - 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
7700 Ω
Transconductance
0.003 S
Amplification factor
20
Max plate voltage
330 V
Max plate dissipation
4 W
Rectifier max heater-cathode voltage
200 V
Rectifier warm-up time
11 s

Published promoted fields populated semantically; identical repeated sections compressed.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0026 S
Amplification factor
20
Max plate voltage
330 V
Max plate dissipation
4 W
Max cathode current
22 mA

Inherited from explicit parent 6FQ7; supplied 8FQ7 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

Characteristic

  • Amplification Factor

    20

    EachUnit

  • Transconductance

    3000 uS

    EachUnit

Data set 02

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage

    8.4 V

    Rated heater condition

  • Heater current

    450 mA

    Rated heater condition

  • Plotecurrent for Grid voltage of

    -12.5 V

    Plotecurrent for Grid voltage of -12.5 Volts.. - 1.3

Data set 03

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 Cathode Current

    330 mA

    HorizontalDeflectionOscillator

Data set 04

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage nominal

    6.3 V

  • Heater current

    600 mA

  • Maximum plate voltage

    330 V

    ClassA1

  • Maximum positive grid voltage

    0 V

    ClassA1

  • Maximum average cathode current

    22 mA

    ClassA1

  • Maximum plate dissipation, either plate

    4 W

    ClassA1

  • Maximum combined plate dissipation

    5.7 W

    ClassA1;TwoTubes

  • Peak heater-cathode voltage, either polarity

    200 V

  • Maximum grid-circuit resistance

    1 MΩ

    ClassA1;FixedBias

  • Maximum plate voltage

    330 V

    HorizontalDeflectionOscillator

  • Peak negative-pulse grid voltage

    660 V

    HorizontalDeflectionOscillator

  • Peak cathode current

    330 mA

    HorizontalDeflectionOscillator

  • Average cathode current

    22 mA

    HorizontalDeflectionOscillator

  • Maximum grid-circuit resistance

    2.2 MΩ

    HorizontalDeflectionOscillator

  • Maximum plate voltage

    330 V

    VerticalDeflectionOscillator

  • Peak negative-pulse grid voltage

    440 V

    VerticalDeflectionOscillator

  • Peak cathode current

    77 mA

    VerticalDeflectionOscillator

  • Average cathode current

    22 mA

    VerticalDeflectionOscillator

  • Maximum grid-circuit resistance

    2.2 MΩ

    VerticalDeflectionOscillator

  • Heater voltage nominal

    8.4 V

  • Heater current nominal

    450 mA

Characteristics

  • Heater warm-up time

    11 s

    Average

  • Plate voltage

    90 V

    ClassA1

  • Grid voltage

    0 V

    ClassA1;PlateVoltage=90V

  • Amplification factor

    20

    ClassA1;PlateVoltage=90V

  • Plate resistance

    6700 ohm

    ClassA1;PlateVoltage=90V

  • Transconductance

    3000 µS

    ClassA1;PlateVoltage=90V

  • Plate current

    10 mA

    ClassA1;PlateVoltage=90V

  • Grid voltage for plate current 10 µA

    -7 V

    ClassA1;PlateVoltage=90V

  • Plate voltage

    250 V

    ClassA1

  • Grid voltage

    -8 V

    ClassA1;PlateVoltage=250V

  • Amplification factor

    20

    ClassA1;PlateVoltage=250V

  • Plate resistance

    7700 ohm

    ClassA1;PlateVoltage=250V

  • Transconductance

    2600 µS

    ClassA1;PlateVoltage=250V

  • Plate current

    9 mA

    ClassA1;PlateVoltage=250V

  • Plate current at grid -12.5 V

    1.3 mA

    ClassA1;PlateVoltage=250V

  • Grid voltage for plate current 10 µA

    -18 V

    ClassA1;PlateVoltage=250V

Capacitance

  • Grid-to-plate capacitance

    3.6 pF

    Section1

  • Grid-to-cathode-and-heater capacitance

    2.4 pF

    Section1

  • Plate-to-cathode-and-heater capacitance

    0.34 pF

    Section1

  • Plate-to-plate interunit capacitance

    1 pF

    BetweenSections

SECTION 2

Triode

Other

  • Heater voltage nominal

    6.3 V

  • Heater current

    600 mA

  • Maximum plate voltage

    330 V

    ClassA1

  • Maximum positive grid voltage

    0 V

    ClassA1

  • Maximum average cathode current

    22 mA

    ClassA1

  • Maximum plate dissipation, either plate

    4 W

    ClassA1

  • Maximum combined plate dissipation

    5.7 W

    ClassA1;TwoTubes

  • Peak heater-cathode voltage, either polarity

    200 V

  • Maximum grid-circuit resistance

    1 MΩ

    ClassA1;FixedBias

  • Maximum plate voltage

    330 V

    HorizontalDeflectionOscillator

  • Peak negative-pulse grid voltage

    660 V

    HorizontalDeflectionOscillator

  • Peak cathode current

    330 mA

    HorizontalDeflectionOscillator

  • Average cathode current

    22 mA

    HorizontalDeflectionOscillator

  • Maximum grid-circuit resistance

    2.2 MΩ

    HorizontalDeflectionOscillator

  • Maximum plate voltage

    330 V

    VerticalDeflectionOscillator

  • Peak negative-pulse grid voltage

    440 V

    VerticalDeflectionOscillator

  • Peak cathode current

    77 mA

    VerticalDeflectionOscillator

  • Average cathode current

    22 mA

    VerticalDeflectionOscillator

  • Maximum grid-circuit resistance

    2.2 MΩ

    VerticalDeflectionOscillator

  • Heater voltage nominal

    8.4 V

  • Heater current nominal

    450 mA

Characteristics

  • Heater warm-up time

    11 s

    Average

  • Plate voltage

    90 V

    ClassA1

  • Grid voltage

    0 V

    ClassA1;PlateVoltage=90V

  • Amplification factor

    20

    ClassA1;PlateVoltage=90V

  • Plate resistance

    6700 ohm

    ClassA1;PlateVoltage=90V

  • Transconductance

    3000 µS

    ClassA1;PlateVoltage=90V

  • Plate current

    10 mA

    ClassA1;PlateVoltage=90V

  • Grid voltage for plate current 10 µA

    -7 V

    ClassA1;PlateVoltage=90V

  • Plate voltage

    250 V

    ClassA1

  • Grid voltage

    -8 V

    ClassA1;PlateVoltage=250V

  • Amplification factor

    20

    ClassA1;PlateVoltage=250V

  • Plate resistance

    7700 ohm

    ClassA1;PlateVoltage=250V

  • Transconductance

    2600 µS

    ClassA1;PlateVoltage=250V

  • Plate current

    9 mA

    ClassA1;PlateVoltage=250V

  • Plate current at grid -12.5 V

    1.3 mA

    ClassA1;PlateVoltage=250V

  • Grid voltage for plate current 10 µA

    -18 V

    ClassA1;PlateVoltage=250V

Capacitance

  • Grid-to-plate capacitance

    3.8 pF

    Section2

  • Grid-to-cathode-and-heater capacitance

    2.4 pF

    Section2

  • Plate-to-cathode-and-heater capacitance

    0.26 pF

    Section2

  • Plate-to-plate interunit capacitance

    1 pF

    BetweenSections

Data set 05

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater Voltage (ac/dc) 6.3 8.4

    12.6 V

    Published in approved 12FQ7 target entry; Section1

  • Heater Current 0.6 0.45

    300 mA

    Published in approved 12FQ7 target entry; Section1

  • Heater Warm-up Time (Average)

    11 seconds

    Published in approved 12FQ7 target entry; Section1

  • Grid to Plate 3.6

    3.8 pF

    Published in approved 12FQ7 target entry; Section1

  • Grid to Cathode and Heater 2.4

    2.4 pF

    Published in approved 12FQ7 target entry; Section1

  • Plate to Cathode and Heater 0.34

    0.26 pF

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    330 V

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage, Positive-bias value

    0 V

    Published in approved 12FQ7 target entry; Section1

  • Cathode Current

    22 mA

    Published in approved 12FQ7 target entry; Section1

  • For both plates with both units opex'ating

    5.7 W

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage 90

    250 V

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage 0

    -8 V

    Published in approved 12FQ7 target entry; Section1

  • Plate Resistance (Approx.) 6700

    7700 Ω

    Published in approved 12FQ7 target entry; Section1

  • DC Plate Voltage 330

    330 V

    Published in approved 12FQ7 target entry; Section1

  • Peak Negative-Pulse Grid Voltage 440

    660 V

    Published in approved 12FQ7 target entry; Section1

  • Peak Cathode Current 77

    330 mA

    Published in approved 12FQ7 target entry; Section1

  • Average Cathode Current 22

    22 mA

    Published in approved 12FQ7 target entry; Section1

  • For either plate 4

    4 W

    Published in approved 12FQ7 target entry; Section1

  • For both plates with both units operating . . . 5.7

    6.7 W

    Published in approved 12FQ7 target entry; Section1

  • Grid-Circuit Resistance 2.2

    2.2 MΩ

    Published in approved 12FQ7 target entry; Section1

  • Heater Voltage (ac/dc) 2.4 2.9

    6.3 V

    Published in approved 12FQ7 target entry; Section1

  • Heater Current 0.6 0.45

    200 mA

    Published in approved 12FQ7 target entry; Section1

  • Heater Warm-up Time (Average) 11

    11 seconds

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    300 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 (Screen-Grid) Voltage

    150 V

    Published in approved 12FQ7 target entry; Section1

  • Negative-bias value

    60 V

    Published in approved 12FQ7 target entry; Section1

  • Positive-bias value

    0 V

    Published in approved 12FQ7 target entry; Section1

  • Cathode Current

    20 mA

    Published in approved 12FQ7 target entry; Section1

  • Plate Dissipation

    3.25 W

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Input

    0.16 W

    Published in approved 12FQ7 target entry; Section1

  • Plate Voltage

    275 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Voltage

    135 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage

    -0.2 V

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l-Circuit Resistance, for fixed-bias operation

    0.5 MΩ

    Published in approved 12FQ7 target entry; Section1

Capacitance

  • Plate of Unit No.l to Plate of Unit No

    2 pF

    Published in approved 12FQ7 target entry; Section1

  • Grid No.l to Plate 0.03

    0.016 pF

    Published in approved 12FQ7 target entry; Section1

  • No.3, and Grid No.4

    4.8 pF

    Published in approved 12FQ7 target entry; Section1

  • and Grid No

    4 pF

    Published in approved 12FQ7 target entry; Section1

Characteristic

  • Plate Current 10

    9 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid Voltage (Approx.) for plate current of 10 /iA. —7

    -18 V

    Published in approved 12FQ7 target entry; Section1

  • 12.5 volts

    1.3 mA

    Published in approved 12FQ7 target entry; Section1

  • Plate Resistance (Approx. )

    0.24 MΩ

    Published in approved 12FQ7 target entry; Section1

  • Transconductance

    10000 µS

    Published in approved 12FQ7 target entry; Section1

  • Plate Current

    9 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.3 Current

    0.17 mA

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage (Approx.) for transconductance of

    100 µS

    Published in approved 12FQ7 target entry; Section1

  • Grid-No.l Voltage (Approx.) for transconductance of 100 /imhos

    -5 V

    Published in approved 12FQ7 target entry; Section1