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Power - Pentode (NOT beam) ·Pentode-Triode

6LQ8

Medium-mu triode plus sharp-cutoff pentode for television receivers. The pentode provides video output while the triode serves sync-separator and sound-IF functions.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9DX
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 775 mA

Description

Medium-mu triode and sharp-cutoff pentode for television receivers; pentode is used as a video output tube and triode in sync-separator and sound-IF circuits.

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
9DX
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
775 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9DX - Terminal pinout

Electrical assignments shared by every tube using this base designation.

TerminalSectionConnectionEvidence
PIN12KBK — Cathode

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN22G1BG1 — Control Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN32PBP — Plate (Anode)

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN4H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN5H—H — Heater

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN61G3AG3 — Suppressor GridGroup 9DX6

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN6ISAIS — Internal ScreenGroup 9DX6

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN61KAK — CathodeGroup 9DX6

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN71G1AG1 — Control Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN81G2AG2 — Screen Grid

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

PIN91PAP — Plate (Anode)

EIA transcription; manufacturer confirmation pending

Unverified

EIA Base Connections, printed page 131, 9DX

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
4400 Ω
Transconductance
0.0104 S
Amplification factor
46
Max plate voltage
300 V
Max plate dissipation
2 W

Published promoted values applied where applicable; additional ratings, characteristics, and operating data retained as parameters.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
55000 Ω
Transconductance
0.023 S
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
5 W
Max screen dissipation
1 W

Published promoted values applied where applicable; additional ratings, characteristics, and operating data retained as parameters.

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

Characteristic

  • Heater Voltage

    6.3 V

  • Heater Current

    775 mA

  • Plate Voltage

    125 V

  • Grid Voltage

    -

  • Plate Current

    15 mA

  • Amplification Factor

    46

  • Plate Resistance

    4400 ohm

  • Transconductance

    10400 uS

  • Grid To Plate Capacitance

    2.8 pF

  • Input Capacitance

    4.2 pF

  • Output Capacitance

    2.4 pF

SECTION 2

Pentode

Characteristic

  • Plate Voltage

    125 V

  • Screen Voltage

    125 V

  • Grid Voltage

    -

  • Plate Current

    16.5 mA

  • Screen Current

    3.1 mA

  • Plate Resistance

    75000 ohm

  • Transconductance

    21000 uS

  • Grid To Plate Capacitance

    0.12 pF

  • Input Capacitance

    14 pF

  • Output Capacitance

    4.8 pF

  • FrameGridConstruction

    1 boolean

  • Application

    Video output

    LowBPlusTelevision

Data set 02

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater Voltage (AC or DC)

    6.3 V

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

  • Heater Current

    0.775

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

  • Grid to plate

    2.8 pF

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

  • Plate Resistance (Approx.) — published value 1

    4400

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

  • Plate Resistance (Approx.) — published value 2

    55000

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

  • Plate Resistance (Approx.) — published value 3

    75000

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

  • Plate Resistance (Approx.) — published value 4

    2

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

  • Transconductance — published value 1

    10400

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

  • Transconductance — published value 2

    21000

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

  • Transconductance — published value 3

    23000

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

  • DC Plate Current — published value 1

    15 mA

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

  • DC Plate Current — published value 2

    16.5 mA

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

  • DC Plate Current — published value 3

    20 mA

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

  • DC Grid-No.2 Current — published value 1

    3 mA

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

  • DC Grid-No.2 Current — published value 2

    1 mA

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

  • DC Grid-No.2 Current — published value 3

    3.5 mA

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

  • Cutoff DC Grid-No. l Voltage — published value 1

    -6 V

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

  • Cutoff DC Grid-No. l Voltage — published value 2

    -4.2 V

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

  • Cutoff DC Grid-No. l Voltage — published value 3

    -4.2 V

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

  • Plate uA = 1C0

    1

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

  • DC Plate Supply Voltage — published value 1

    125 V

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

  • DC Plate Supply Voltage — published value 2

    125 V

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

  • DC Plate Supply Voltage — published value 3

    200 V

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

  • DC Grid-No.2 Supply Voltage • — published value 1

    125 V

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

  • DC Grid-No.2 Supply Voltage • — published value 2

    125 V

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

  • Cathode Resistor — published value 1

    68

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

  • Cathode Resistor — published value 2

    82

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

  • Cathode Resistor — published value 3

    68

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

  • Pin 1 -Triode Cathode

    1

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

  • Pin 2 -Triode Grid

    2

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

  • Pin 3-Triode Plate

    3

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

  • Pin 4 -Heater

    4

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

  • Pin 5 -Heater

    5

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

  • DC Plate Voltage — published value 1

    300 V

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

  • DC Plate Voltage — published value 2

    300 V

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

  • Supply Voltage

    300 V

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

  • Positive-bias value — published value 1

    0

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

  • Positive-bias value — published value 2

    0

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

  • Heater Voltage (AC or DC) — published value 1

    5.7 V

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

  • Heater Voltage (AC or DC) — published value 2

    6.9 V

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

  • For Ec2 > 150 V and < 300 V — published value 1

    150

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

  • For Ec2 > 150 V and < 300 V — published value 2

    300

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

  • Plate Dissipation — published value 1

    2

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

  • Plate Dissipation — published value 2

    5

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

  • For fixed-bias operation — published value 1

    0.5

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

  • For fixed-bias operation — published value 2

    0.1

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

  • For fixed-bias operation — published value 3

    1

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

  • Far cathode-bias operation

    0.25

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

  • PLATE VOLTS~200

    200 V

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

  • GRID-No.2 VOLTS=125

    125 V

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

  • GRID-No.2 VOLTS'125

    125 V

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

  • PLATE (Iy) OR GRID-No.2 (I~ 2) MILLIAMPERES

    2 mA

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

Other

  • Grid No.1 to plate — published value 1

    1 mA

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

  • Grid No.1 to plate — published value 2

    0.12 mA

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

SECTION 2

Pentode

Other

  • Triode grid to pentode Glate

    0.015 mA

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

  • Pentode plate to triode plate — published value 1

    0 mA

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

  • Pentode plate to triode plate — published value 2

    17 mA

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

Characteristics

  • Pin 6- Pentode Grid No.3,

    6

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

  • Pin 7- Pentode Grid No.1

    7

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

  • Pin 8- Pentode Grid No.2

    8

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

  • Pin 9 - Pentode Plate

    9

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

Data set 03

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater Voltage

    6.3 V

    Nominal

  • Heater Current

    700 mA

    Nominal

  • Plate Supply Voltage

    125 V

    ClassA

  • Cathode-Bias Resistor

    68 ohm

    ClassA

  • Plate Current

    15 mA

    ClassA

Capacitance

  • Grid-to-Plate Capacitance

    2.8 pF

  • Grid Input Capacitance

    4.2 pF

  • Plate Output Capacitance

    2.4 pF

SECTION 2

Pentode

Capacitance

  • Grid No.1-to-Plate Capacitance

    0.12 pF

  • Grid No.1 Input Capacitance

    14 pF

  • Plate Output Capacitance

    4.8 pF

  • Triode Grid-to-Pentode Plate Capacitance

    0.015 pF

  • Pentode Plate-to-Triode Plate Capacitance

    0.17 pF

Other

  • Plate Supply Voltage

    200 V

    ClassA

  • Screen Supply Voltage

    125 V

    ClassA

  • Cathode-Bias Resistor

    68 ohm

    ClassA

  • Plate Current

    20 mA

    ClassA

  • Screen Current

    3.5 mA

    ClassA