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Voltage Pentode - Sharp Cutoff (single) ·Pentode-Triode

6CU8

Medium-mu triode plus sharp-cutoff pentode for a wide range of black-and-white and color television circuits, with controlled heater warm-up.

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

Description

The 6CU8 combines a medium-mu triode with a sharp-cutoff pentode and is intended for a wide range of black-and-white and color television applications. Its controlled heater warm-up supports series-string television receiver use.

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
450 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
4100 Ω
Transconductance
0.0058 S
Amplification factor
28
Max plate voltage
330 V
Max plate dissipation
2.8 W

Published promoted fields populated from printed headings.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
170000 Ω
Transconductance
0.0078 S
Max plate voltage
330 V
Max screen voltage
330 V
Max plate dissipation
2.3 W
Max screen dissipation
0.55 W

Published promoted fields populated from printed headings.

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

  • TriodeTransconductance

    5800 uS

    Section1

SECTION 2

Pentode

Characteristic

  • PentodeTransconductance

    7800 uS

    Section2

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

    125 V

    ClassA

  • Grid-1 voltage

    -1 V

    ClassA

Characteristic

  • Plate current

    17 mA

    ClassA

SECTION 2

Pentode

Other

  • Plate voltage

    125 V

    ClassA

  • Grid-2 voltage

    125 V

    ClassA

  • Cathode-bias resistor

    56 ohm

    ClassA

Characteristic

  • Plate current

    12 mA

    ClassA

  • Grid-2 current

    3.8 mA

    ClassA

Data set 03

1971 RCA HB3 Binder 4 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Voltage (AC or DC)

    6.3 V

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

  • Current — published value 1

    0 mA

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

  • Current — published value 2

    45 A

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

  • Current — published value 3

    6 A

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

  • Grid to plate

    1.6

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

  • 8 internal shield, and heater — published value 1

    8

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

  • 8 internal shield, and heater — published value 2

    1.9

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

  • & internal shield, and heater

    1.6

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

  • grid No.2, and heater

    7

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

  • grid No.2, and heater

    2.4

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

  • Plate Supply Voltage — published value 1

    125 V

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

  • Plate Supply Voltage — published value 2

    125 V

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

  • Grid-No.2 Supply Voltage

    125 V

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

  • Grid-No.l Voltage — published value 1

    -1 V

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

  • Grid-No.l Voltage — published value 2

    0 V

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

  • Cathode Resistor — published value 1

    0 ohm

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

  • Cathode Resistor — published value 2

    56 ohm

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

  • Plate Resistance (Approx ) — published value 1

    4100 ohm

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

  • Plate Resistance (Approx ) — published value 2

    170000 ohm

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

  • Transconductance — published value 1

    5800

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

  • Transconductance — published value 2

    7800

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

  • Plate Current — published value 1

    17 mA

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

  • Plate Current — published value 2

    12 mA

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

  • Grid-No.2 Current

    3.8 mA

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

  • plate µa = 20 — published value 1

    20 V

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

  • plate µa = 20 — published value 2

    -12 V

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

  • plate µa = 20 — published value 3

    -6 V

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

  • plate ma. = 1.6, and cathode

    1.6 mA

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

  • Pin 1 -Triode — published value 1

    1

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

  • Pin 1 -Triode — published value 2

    4

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

  • Cathode,

    5

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

  • between 165 and 330 volts — published value 1

    165 V

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

  • between 165 and 330 volts — published value 2

    330 V

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

  • PLATE VOLTS=125

    125 V

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

  • GRID-N42 VOLTS=125 ■■■■■■■■■■■■■■ — published value 1

    125 V

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

  • GRID-N42 VOLTS=125 ■■■■■■■■■■■■■■ — published value 2

    1 V

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

  • GRID-N42 VOLTS=125 ■■■■■■■■■■■■■■ — published value 3

    1 V

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

  • GRID-Nsp VOLTS=125

    125 V

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

Other

  • Grid No.l to plate

    0.025 mA

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

  • PLATE VOLTAGE — published value 1

    330 V

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

  • PLATE VOLTAGE — published value 2

    330 V

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

  • SUPPLY VOLTAGE

    330 V

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

  • Positive-bias value — published value 1

    0 V

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

  • Positive-bias value — published value 2

    0 V

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

  • PLATE DISSIPATION — published value 1

    2.8 mA

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

  • PLATE DISSIPATION — published value 2

    2.3 mA

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

  • respect to cathode — published value 1

    200 V

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

  • respect to cathode — published value 2

    200 V

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

SECTION 2

Pentode

Other

  • Pentode grid No.l to triode plate

    0.03 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

    7 mA

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