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Voltage - Triple Triode ·Triode-Triode-Triode

6MD8

Medium-mu triple triode for matrixing circuits in color and black-and-white television receivers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
9RQ
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 900 mA

Description

Medium-mu triple triode for matrixing circuits in color and black-and-white television receivers. Explicit heater variant/co-designation of 12MD8 in the approved source.

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

9RQ - Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

3 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
5500 Ω
Transconductance
0.0031 S
Amplification factor
17
Max plate voltage
330 V
Max plate dissipation
3 W

Representative specification for all three identical triode sections; values semantically read from current OCR PDF.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
5500 Ω
Transconductance
0.0031 S
Max plate voltage
250 V
Max plate dissipation
3 W

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

Section 3

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
5500 Ω
Transconductance
0.0031 S
Max plate dissipation
3 W

Third physical triode section; added to align rows with SectionCount while avoiding conflicting source-point promotions.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum Plate Voltage

    330 V

  • Maximum Plate Dissipation

    3 W

  • Typical Plate Voltage

    250 V

    ClassA

  • TypicalGridVoltage

    -10.5 V

    ClassA

  • Typical Plate Current

    11.5 mA

    ClassA

Characteristic

  • Amplification Factor

    17

  • Plate Resistance

    5500 ohm

  • Transconductance

    3100 uS

Capacitance

  • Grid To Plate Capacitance

    3 pF

    Section1

  • Input Capacitance

    3.6 pF

    Section1

  • Output Capacitance

    0.48 pF

    Section1

  • Grid To Plate Capacitance

    3 pF

    Section2

  • Input Capacitance

    3.6 pF

    Section2

  • Output Capacitance

    0.48 pF

    Section2

  • Grid To Plate Capacitance

    3 pF

    Section3

  • Input Capacitance

    3.4 pF

    Section3

  • Output Capacitance

    0.36 pF

    Section3

Data set 02

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Voltage (AC or DC) — published value 1

    6 V

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

  • Voltage (AC or DC) — published value 2

    3 V

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

  • Voltage (AC or DC) — published value 3

    0.6 V

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

  • Current at 6.3 V — published value 1

    6.3

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

  • Current at 6.3 V — published value 2

    0.9

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

  • Grid to plate — published value 1

    3 pF

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

  • Grid to plate — published value 2

    0 pF

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

  • Grid to plate — published value 3

    3 pF

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

  • Grid to plate — published value 4

    3 pF

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

  • Pin 1 - Plate of Unit No.3

    1

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

  • Pin 2 - Plate of Unit No.2

    2

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

  • Pin 3 - Plate of Unit No.1

    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.

  • Pin 6 -Grid of Unit No.1

    6

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

  • Pin 7 -Cathode

    7

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

  • Pin 8 -Grid of Unit No.2

    8

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

  • Pin 9 -Grid of Unit No.3

    9

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

  • Plate Voltage

    250 V

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

  • Grid Voltage — published value 1

    -10 V

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

  • Grid Voltage — published value 2

    5 V

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

  • Plate Resistance (Approx.)

    5500

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

  • Transconductance

    3100

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

  • Plate Current — published value 1

    1 mA

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

  • Plate Current — published value 2

    1.5 mA

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

  • Plate Current for grid volts = -14 — published value 1

    -14 V

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

  • Plate Current for grid volts = -14 — published value 2

    4 V

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

  • Grid Voltage (Approx.)forplate µA = 50 — published value 1

    50 V

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

  • Grid Voltage (Approx.)forplate µA = 50 — published value 2

    -23 V

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

  • Plate Voltage

    330 V

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

  • Positive-bias value

    0

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

  • Plate Dissipation

    3

    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 Warm-up Time (Average) —

    11 s

    Other

  • Peak value

    200 V

    Other;PublishedValue1

  • Peak value

    200 V

    Other;PublishedValue2

  • Average value

    100 V

    Other;PublishedValue1

  • Average value

    100 V

    Other;PublishedValue2

  • Plate Voltage

    330 V

    MaximumRating

  • Grid Voltage, Positive-bias value

    0 V

    MaximumRating

  • Plate Dissipation

    3 W

    MaximumRating

  • Grid-Circuit Resistance, for fixed-bias operation

    1 megohm

    MaximumCircuitValue

  • Maximum Plate Voltage

    330 V

    Section1

  • Maximum Plate Dissipation

    3 W

    Section1

Capacitance

  • Grid to Plate

    3 pF

    Capacitance;PublishedValue1

  • Grid to Plate

    3 pF

    Capacitance;PublishedValue2

  • Grid to Plate

    3 pF

    Capacitance;PublishedValue3

  • Grid to Cathode and Heater

    3.6 pF

    Capacitance;PublishedValue1

  • Grid to Cathode and Heater

    3.6 pF

    Capacitance;PublishedValue2

  • Grid to Cathode and Heater

    3.4 pF

    Capacitance;PublishedValue3

  • Plate to Cathode and Heater

    0.48 pF

    Capacitance;PublishedValue1

  • Plate to Cathode and Heater

    0.48 pF

    Capacitance;PublishedValue2

  • Plate to Cathode and Heater

    0.36 pF

    Capacitance;PublishedValue3

Characteristic

  • Plate Voltage

    2 V

    Characteristic

  • Grid Voltage

    -10.5 V

    Characteristic

  • PLATE

    92 V

    Characteristic

  • Plate Current

    11.5 mA

    Characteristic

  • Plate Current for grid voltage of —

    14 V

    Characteristic;PublishedValue1

  • Plate Current for grid voltage of —

    4 V

    Characteristic;PublishedValue2

  • Grid Voltage (Approx.) for plate current of

    50 V

    Characteristic;PublishedValue1

  • Grid Voltage (Approx.) for plate current of

    -23 V

    Characteristic;PublishedValue2

  • Plate Resistance

    5500 ohm

    Section1

  • Transconductance

    3100 uS

    Section1

  • Amplification Factor

    17

    Section1