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Power - TV Vertical Output ·BeamPower-Triode

31LR8

Multi-section television tube incorporating a beam-power section explicitly intended for vertical-deflection amplification, with substantial pulse-current and plate-dissipation capability.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9QT
Socket code
B9A
Base pins
9
Nominal heater
31.5 V / 300 mA

Description

High-mu triode plus beam-power section used as a combined vertical-deflection oscillator and amplifier 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
9QT
Socket code
B9A
Base pins
9
Nominal heater voltage
31.5 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9QT - 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
14000 Ω
Transconductance
0.0041 S
Amplification factor
58
Max plate voltage
400 V
Max plate dissipation
2.5 W
Max cathode current
30 mA

High-mu vertical-oscillator triode; source sheet states electrical identity to 6LR8/21LR8 except heater.

Section 2

Beam Power

X-ray radiationInterelectrode capacitances
Plate resistance
14000 Ω
Transconductance
0.0092 S
Amplification factor
6.5
Max plate voltage
400 V
Max screen voltage
300 V
Max plate dissipation
14 W
Max cathode current
75 mA

Vertical-deflection beam-power pentode; source sheet states electrical identity to 6LR8/21LR8 except heater.

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

1964 RMA EIA

Published operating points and test conditions from this source.

SECTION 1

Triode

CrossReference

  • Cross-reference / electrical identity

    6LR8 / 21LR8

Application

  • Application

    Vertical oscillator

SECTION 2

Beam Power

Application

  • Application

    Vertical-deflection amplifier

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater Voltage 6.3 21

    31.5 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Heater Current 1.5 0.45

    300 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Heater Warm-up Time . 11

    11 seconds

    Published in approved 31LR8 target datasheet entry; Section1

  • Flate Voltage 400

    400 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.2 Voltage

    300 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Peak Cathode Current 105

    260 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Average Cathode Current 30

    75 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Dissipation!: 2.5

    14 W

    Published in approved 31LR8 target datasheet entry; Section1

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

    10 microseconds

    Published in approved 31LR8 target datasheet entry; Section1

  • Heater Voltage 6.3 8.1

    11.4 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Heater Current 0.6 0.45

    315 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Heater Warm-up Time (Average) 11 11

    11 seconds

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Voltage

    330 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.2 (Screen-Grid) Supply Voltage

    330 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.l (Control-Grid) Voltage, Positive-bias value

    0 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Dissipation

    3.1 W

    Published in approved 31LR8 target datasheet entry; Section1

  • For grid-No 2 voltages up to

    165 V

    Published in approved 31LR8 target datasheet entry; Section1

  • For grid-No 2 voltages up to 165 volts

    0.65 W

    Published in approved 31LR8 target datasheet entry; Section1

  • For grid-No.2 voltages between 165 and

    33 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Voltage

    125 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.2 Voltage

    125 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Cathode-Bias Resistor

    56 Ω

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Resistance (Approx.)

    200000 Ω

    Published in approved 31LR8 target datasheet entry; Section1

Characteristic

  • Plate Voltage 250 45 135

    120 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.l (Control-Grid) Voltage —4 0 —10

    -10 V

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Resistance Approx.) 14000

    14000 Ω

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Current 2.S 200

    51 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • For plate current of

    1 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Transconductance

    13000 µS

    Published in approved 31LR8 target datasheet entry; Section1

  • Plate Current

    10 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.2 Current

    3.4 mA

    Published in approved 31LR8 target datasheet entry; Section1

  • Grid-No.l Voltage (Approx.) for plate current of 20 /lA

    -3.5 V

    Published in approved 31LR8 target datasheet entry; Section1

SECTION 2

Beam Power

Other

  • Heater Voltage 6.3 21

    31.5 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Heater Current 1.5 0.45

    300 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Heater Warm-up Time . 11

    11 seconds

    Published in approved 31LR8 target datasheet entry; Section2

  • Flate Voltage 400

    400 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.2 Voltage

    300 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Peak Cathode Current 105

    260 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Average Cathode Current 30

    75 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Dissipation!: 2.5

    14 W

    Published in approved 31LR8 target datasheet entry; Section2

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

    10 microseconds

    Published in approved 31LR8 target datasheet entry; Section2

  • Heater Voltage 6.3 8.1

    11.4 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Heater Current 0.6 0.45

    315 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Heater Warm-up Time (Average) 11 11

    11 seconds

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Voltage

    330 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.2 (Screen-Grid) Supply Voltage

    330 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.l (Control-Grid) Voltage, Positive-bias value

    0 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Dissipation

    3.1 W

    Published in approved 31LR8 target datasheet entry; Section2

  • For grid-No 2 voltages up to

    165 V

    Published in approved 31LR8 target datasheet entry; Section2

  • For grid-No 2 voltages up to 165 volts

    0.65 W

    Published in approved 31LR8 target datasheet entry; Section2

  • For grid-No.2 voltages between 165 and

    33 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Voltage

    125 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.2 Voltage

    125 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Cathode-Bias Resistor

    56 Ω

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Resistance (Approx.)

    200000 Ω

    Published in approved 31LR8 target datasheet entry; Section2

Characteristic

  • Plate Voltage 250 45 135

    120 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.l (Control-Grid) Voltage —4 0 —10

    -10 V

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Resistance Approx.) 14000

    14000 Ω

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Current 2.S 200

    51 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • For plate current of

    1 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Transconductance

    13000 µS

    Published in approved 31LR8 target datasheet entry; Section2

  • Plate Current

    10 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.2 Current

    3.4 mA

    Published in approved 31LR8 target datasheet entry; Section2

  • Grid-No.l Voltage (Approx.) for plate current of 20 /lA

    -3.5 V

    Published in approved 31LR8 target datasheet entry; Section2